AbsListView.java revision f7dee54b62b02413fc6a0b8dc5666a7cd9758460
1/* 2 * Copyright (C) 2006 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17package android.widget; 18 19import android.content.Context; 20import android.content.Intent; 21import android.content.res.TypedArray; 22import android.graphics.Canvas; 23import android.graphics.Rect; 24import android.graphics.drawable.Drawable; 25import android.graphics.drawable.TransitionDrawable; 26import android.os.Bundle; 27import android.os.Debug; 28import android.os.Parcel; 29import android.os.Parcelable; 30import android.os.StrictMode; 31import android.os.Trace; 32import android.text.Editable; 33import android.text.InputType; 34import android.text.TextUtils; 35import android.text.TextWatcher; 36import android.util.AttributeSet; 37import android.util.Log; 38import android.util.LongSparseArray; 39import android.util.SparseArray; 40import android.util.SparseBooleanArray; 41import android.util.StateSet; 42import android.view.ActionMode; 43import android.view.ContextMenu.ContextMenuInfo; 44import android.view.Gravity; 45import android.view.HapticFeedbackConstants; 46import android.view.InputDevice; 47import android.view.KeyEvent; 48import android.view.LayoutInflater; 49import android.view.Menu; 50import android.view.MenuItem; 51import android.view.MotionEvent; 52import android.view.VelocityTracker; 53import android.view.View; 54import android.view.ViewConfiguration; 55import android.view.ViewDebug; 56import android.view.ViewGroup; 57import android.view.ViewParent; 58import android.view.ViewTreeObserver; 59import android.view.accessibility.AccessibilityEvent; 60import android.view.accessibility.AccessibilityManager; 61import android.view.accessibility.AccessibilityNodeInfo; 62import android.view.accessibility.AccessibilityNodeInfo.CollectionInfo; 63import android.view.animation.Interpolator; 64import android.view.animation.LinearInterpolator; 65import android.view.inputmethod.BaseInputConnection; 66import android.view.inputmethod.CompletionInfo; 67import android.view.inputmethod.CorrectionInfo; 68import android.view.inputmethod.EditorInfo; 69import android.view.inputmethod.ExtractedText; 70import android.view.inputmethod.ExtractedTextRequest; 71import android.view.inputmethod.InputConnection; 72import android.view.inputmethod.InputMethodManager; 73import android.widget.RemoteViews.OnClickHandler; 74 75import com.android.internal.R; 76 77import java.util.ArrayList; 78import java.util.List; 79 80/** 81 * Base class that can be used to implement virtualized lists of items. A list does 82 * not have a spatial definition here. For instance, subclases of this class can 83 * display the content of the list in a grid, in a carousel, as stack, etc. 84 * 85 * @attr ref android.R.styleable#AbsListView_listSelector 86 * @attr ref android.R.styleable#AbsListView_drawSelectorOnTop 87 * @attr ref android.R.styleable#AbsListView_stackFromBottom 88 * @attr ref android.R.styleable#AbsListView_scrollingCache 89 * @attr ref android.R.styleable#AbsListView_textFilterEnabled 90 * @attr ref android.R.styleable#AbsListView_transcriptMode 91 * @attr ref android.R.styleable#AbsListView_cacheColorHint 92 * @attr ref android.R.styleable#AbsListView_fastScrollEnabled 93 * @attr ref android.R.styleable#AbsListView_smoothScrollbar 94 * @attr ref android.R.styleable#AbsListView_choiceMode 95 */ 96public abstract class AbsListView extends AdapterView<ListAdapter> implements TextWatcher, 97 ViewTreeObserver.OnGlobalLayoutListener, Filter.FilterListener, 98 ViewTreeObserver.OnTouchModeChangeListener, 99 RemoteViewsAdapter.RemoteAdapterConnectionCallback { 100 101 @SuppressWarnings("UnusedDeclaration") 102 private static final String TAG = "AbsListView"; 103 104 /** 105 * Disables the transcript mode. 106 * 107 * @see #setTranscriptMode(int) 108 */ 109 public static final int TRANSCRIPT_MODE_DISABLED = 0; 110 111 /** 112 * The list will automatically scroll to the bottom when a data set change 113 * notification is received and only if the last item is already visible 114 * on screen. 115 * 116 * @see #setTranscriptMode(int) 117 */ 118 public static final int TRANSCRIPT_MODE_NORMAL = 1; 119 120 /** 121 * The list will automatically scroll to the bottom, no matter what items 122 * are currently visible. 123 * 124 * @see #setTranscriptMode(int) 125 */ 126 public static final int TRANSCRIPT_MODE_ALWAYS_SCROLL = 2; 127 128 /** 129 * Indicates that we are not in the middle of a touch gesture 130 */ 131 static final int TOUCH_MODE_REST = -1; 132 133 /** 134 * Indicates we just received the touch event and we are waiting to see if the it is a tap or a 135 * scroll gesture. 136 */ 137 static final int TOUCH_MODE_DOWN = 0; 138 139 /** 140 * Indicates the touch has been recognized as a tap and we are now waiting to see if the touch 141 * is a longpress 142 */ 143 static final int TOUCH_MODE_TAP = 1; 144 145 /** 146 * Indicates we have waited for everything we can wait for, but the user's finger is still down 147 */ 148 static final int TOUCH_MODE_DONE_WAITING = 2; 149 150 /** 151 * Indicates the touch gesture is a scroll 152 */ 153 static final int TOUCH_MODE_SCROLL = 3; 154 155 /** 156 * Indicates the view is in the process of being flung 157 */ 158 static final int TOUCH_MODE_FLING = 4; 159 160 /** 161 * Indicates the touch gesture is an overscroll - a scroll beyond the beginning or end. 162 */ 163 static final int TOUCH_MODE_OVERSCROLL = 5; 164 165 /** 166 * Indicates the view is being flung outside of normal content bounds 167 * and will spring back. 168 */ 169 static final int TOUCH_MODE_OVERFLING = 6; 170 171 /** 172 * Regular layout - usually an unsolicited layout from the view system 173 */ 174 static final int LAYOUT_NORMAL = 0; 175 176 /** 177 * Show the first item 178 */ 179 static final int LAYOUT_FORCE_TOP = 1; 180 181 /** 182 * Force the selected item to be on somewhere on the screen 183 */ 184 static final int LAYOUT_SET_SELECTION = 2; 185 186 /** 187 * Show the last item 188 */ 189 static final int LAYOUT_FORCE_BOTTOM = 3; 190 191 /** 192 * Make a mSelectedItem appear in a specific location and build the rest of 193 * the views from there. The top is specified by mSpecificTop. 194 */ 195 static final int LAYOUT_SPECIFIC = 4; 196 197 /** 198 * Layout to sync as a result of a data change. Restore mSyncPosition to have its top 199 * at mSpecificTop 200 */ 201 static final int LAYOUT_SYNC = 5; 202 203 /** 204 * Layout as a result of using the navigation keys 205 */ 206 static final int LAYOUT_MOVE_SELECTION = 6; 207 208 /** 209 * Normal list that does not indicate choices 210 */ 211 public static final int CHOICE_MODE_NONE = 0; 212 213 /** 214 * The list allows up to one choice 215 */ 216 public static final int CHOICE_MODE_SINGLE = 1; 217 218 /** 219 * The list allows multiple choices 220 */ 221 public static final int CHOICE_MODE_MULTIPLE = 2; 222 223 /** 224 * The list allows multiple choices in a modal selection mode 225 */ 226 public static final int CHOICE_MODE_MULTIPLE_MODAL = 3; 227 228 /** 229 * The thread that created this view. 230 */ 231 private final Thread mOwnerThread; 232 233 /** 234 * Controls if/how the user may choose/check items in the list 235 */ 236 int mChoiceMode = CHOICE_MODE_NONE; 237 238 /** 239 * Controls CHOICE_MODE_MULTIPLE_MODAL. null when inactive. 240 */ 241 ActionMode mChoiceActionMode; 242 243 /** 244 * Wrapper for the multiple choice mode callback; AbsListView needs to perform 245 * a few extra actions around what application code does. 246 */ 247 MultiChoiceModeWrapper mMultiChoiceModeCallback; 248 249 /** 250 * Running count of how many items are currently checked 251 */ 252 int mCheckedItemCount; 253 254 /** 255 * Running state of which positions are currently checked 256 */ 257 SparseBooleanArray mCheckStates; 258 259 /** 260 * Running state of which IDs are currently checked. 261 * If there is a value for a given key, the checked state for that ID is true 262 * and the value holds the last known position in the adapter for that id. 263 */ 264 LongSparseArray<Integer> mCheckedIdStates; 265 266 /** 267 * Controls how the next layout will happen 268 */ 269 int mLayoutMode = LAYOUT_NORMAL; 270 271 /** 272 * Should be used by subclasses to listen to changes in the dataset 273 */ 274 AdapterDataSetObserver mDataSetObserver; 275 276 /** 277 * The adapter containing the data to be displayed by this view 278 */ 279 ListAdapter mAdapter; 280 281 /** 282 * The remote adapter containing the data to be displayed by this view to be set 283 */ 284 private RemoteViewsAdapter mRemoteAdapter; 285 286 /** 287 * If mAdapter != null, whenever this is true the adapter has stable IDs. 288 */ 289 boolean mAdapterHasStableIds; 290 291 /** 292 * This flag indicates the a full notify is required when the RemoteViewsAdapter connects 293 */ 294 private boolean mDeferNotifyDataSetChanged = false; 295 296 /** 297 * Indicates whether the list selector should be drawn on top of the children or behind 298 */ 299 boolean mDrawSelectorOnTop = false; 300 301 /** 302 * The drawable used to draw the selector 303 */ 304 Drawable mSelector; 305 306 /** 307 * The current position of the selector in the list. 308 */ 309 int mSelectorPosition = INVALID_POSITION; 310 311 /** 312 * Defines the selector's location and dimension at drawing time 313 */ 314 Rect mSelectorRect = new Rect(); 315 316 /** 317 * The data set used to store unused views that should be reused during the next layout 318 * to avoid creating new ones 319 */ 320 final RecycleBin mRecycler = new RecycleBin(); 321 322 /** 323 * The selection's left padding 324 */ 325 int mSelectionLeftPadding = 0; 326 327 /** 328 * The selection's top padding 329 */ 330 int mSelectionTopPadding = 0; 331 332 /** 333 * The selection's right padding 334 */ 335 int mSelectionRightPadding = 0; 336 337 /** 338 * The selection's bottom padding 339 */ 340 int mSelectionBottomPadding = 0; 341 342 /** 343 * This view's padding 344 */ 345 Rect mListPadding = new Rect(); 346 347 /** 348 * Subclasses must retain their measure spec from onMeasure() into this member 349 */ 350 int mWidthMeasureSpec = 0; 351 352 /** 353 * The top scroll indicator 354 */ 355 View mScrollUp; 356 357 /** 358 * The down scroll indicator 359 */ 360 View mScrollDown; 361 362 /** 363 * When the view is scrolling, this flag is set to true to indicate subclasses that 364 * the drawing cache was enabled on the children 365 */ 366 boolean mCachingStarted; 367 boolean mCachingActive; 368 369 /** 370 * The position of the view that received the down motion event 371 */ 372 int mMotionPosition; 373 374 /** 375 * The offset to the top of the mMotionPosition view when the down motion event was received 376 */ 377 int mMotionViewOriginalTop; 378 379 /** 380 * The desired offset to the top of the mMotionPosition view after a scroll 381 */ 382 int mMotionViewNewTop; 383 384 /** 385 * The X value associated with the the down motion event 386 */ 387 int mMotionX; 388 389 /** 390 * The Y value associated with the the down motion event 391 */ 392 int mMotionY; 393 394 /** 395 * One of TOUCH_MODE_REST, TOUCH_MODE_DOWN, TOUCH_MODE_TAP, TOUCH_MODE_SCROLL, or 396 * TOUCH_MODE_DONE_WAITING 397 */ 398 int mTouchMode = TOUCH_MODE_REST; 399 400 /** 401 * Y value from on the previous motion event (if any) 402 */ 403 int mLastY; 404 405 /** 406 * How far the finger moved before we started scrolling 407 */ 408 int mMotionCorrection; 409 410 /** 411 * Determines speed during touch scrolling 412 */ 413 private VelocityTracker mVelocityTracker; 414 415 /** 416 * Handles one frame of a fling 417 */ 418 private FlingRunnable mFlingRunnable; 419 420 /** 421 * Handles scrolling between positions within the list. 422 */ 423 AbsPositionScroller mPositionScroller; 424 425 /** 426 * The offset in pixels form the top of the AdapterView to the top 427 * of the currently selected view. Used to save and restore state. 428 */ 429 int mSelectedTop = 0; 430 431 /** 432 * Indicates whether the list is stacked from the bottom edge or 433 * the top edge. 434 */ 435 boolean mStackFromBottom; 436 437 /** 438 * When set to true, the list automatically discards the children's 439 * bitmap cache after scrolling. 440 */ 441 boolean mScrollingCacheEnabled; 442 443 /** 444 * Whether or not to enable the fast scroll feature on this list 445 */ 446 boolean mFastScrollEnabled; 447 448 /** 449 * Whether or not to always show the fast scroll feature on this list 450 */ 451 boolean mFastScrollAlwaysVisible; 452 453 /** 454 * Optional callback to notify client when scroll position has changed 455 */ 456 private OnScrollListener mOnScrollListener; 457 458 /** 459 * Keeps track of our accessory window 460 */ 461 PopupWindow mPopup; 462 463 /** 464 * Used with type filter window 465 */ 466 EditText mTextFilter; 467 468 /** 469 * Indicates whether to use pixels-based or position-based scrollbar 470 * properties. 471 */ 472 private boolean mSmoothScrollbarEnabled = true; 473 474 /** 475 * Indicates that this view supports filtering 476 */ 477 private boolean mTextFilterEnabled; 478 479 /** 480 * Indicates that this view is currently displaying a filtered view of the data 481 */ 482 private boolean mFiltered; 483 484 /** 485 * Rectangle used for hit testing children 486 */ 487 private Rect mTouchFrame; 488 489 /** 490 * The position to resurrect the selected position to. 491 */ 492 int mResurrectToPosition = INVALID_POSITION; 493 494 private ContextMenuInfo mContextMenuInfo = null; 495 496 /** 497 * Maximum distance to record overscroll 498 */ 499 int mOverscrollMax; 500 501 /** 502 * Content height divided by this is the overscroll limit. 503 */ 504 static final int OVERSCROLL_LIMIT_DIVISOR = 3; 505 506 /** 507 * How many positions in either direction we will search to try to 508 * find a checked item with a stable ID that moved position across 509 * a data set change. If the item isn't found it will be unselected. 510 */ 511 private static final int CHECK_POSITION_SEARCH_DISTANCE = 20; 512 513 /** 514 * Used to request a layout when we changed touch mode 515 */ 516 private static final int TOUCH_MODE_UNKNOWN = -1; 517 private static final int TOUCH_MODE_ON = 0; 518 private static final int TOUCH_MODE_OFF = 1; 519 520 private int mLastTouchMode = TOUCH_MODE_UNKNOWN; 521 522 private static final boolean PROFILE_SCROLLING = false; 523 private boolean mScrollProfilingStarted = false; 524 525 private static final boolean PROFILE_FLINGING = false; 526 private boolean mFlingProfilingStarted = false; 527 528 /** 529 * The StrictMode "critical time span" objects to catch animation 530 * stutters. Non-null when a time-sensitive animation is 531 * in-flight. Must call finish() on them when done animating. 532 * These are no-ops on user builds. 533 */ 534 private StrictMode.Span mScrollStrictSpan = null; 535 private StrictMode.Span mFlingStrictSpan = null; 536 537 /** 538 * The last CheckForLongPress runnable we posted, if any 539 */ 540 private CheckForLongPress mPendingCheckForLongPress; 541 542 /** 543 * The last CheckForTap runnable we posted, if any 544 */ 545 private CheckForTap mPendingCheckForTap; 546 547 /** 548 * The last CheckForKeyLongPress runnable we posted, if any 549 */ 550 private CheckForKeyLongPress mPendingCheckForKeyLongPress; 551 552 /** 553 * Acts upon click 554 */ 555 private AbsListView.PerformClick mPerformClick; 556 557 /** 558 * Delayed action for touch mode. 559 */ 560 private Runnable mTouchModeReset; 561 562 /** 563 * This view is in transcript mode -- it shows the bottom of the list when the data 564 * changes 565 */ 566 private int mTranscriptMode; 567 568 /** 569 * Indicates that this list is always drawn on top of a solid, single-color, opaque 570 * background 571 */ 572 private int mCacheColorHint; 573 574 /** 575 * The select child's view (from the adapter's getView) is enabled. 576 */ 577 private boolean mIsChildViewEnabled; 578 579 /** 580 * The last scroll state reported to clients through {@link OnScrollListener}. 581 */ 582 private int mLastScrollState = OnScrollListener.SCROLL_STATE_IDLE; 583 584 /** 585 * Helper object that renders and controls the fast scroll thumb. 586 */ 587 private FastScroller mFastScroll; 588 589 /** 590 * Temporary holder for fast scroller style until a FastScroller object 591 * is created. 592 */ 593 private int mFastScrollStyle; 594 595 private boolean mGlobalLayoutListenerAddedFilter; 596 597 private int mTouchSlop; 598 private float mDensityScale; 599 600 private InputConnection mDefInputConnection; 601 private InputConnectionWrapper mPublicInputConnection; 602 603 private Runnable mClearScrollingCache; 604 Runnable mPositionScrollAfterLayout; 605 private int mMinimumVelocity; 606 private int mMaximumVelocity; 607 private float mVelocityScale = 1.0f; 608 609 final boolean[] mIsScrap = new boolean[1]; 610 611 private final int[] mScrollOffset = new int[2]; 612 private final int[] mScrollConsumed = new int[2]; 613 614 // Used for offsetting MotionEvents that we feed to the VelocityTracker. 615 // In the future it would be nice to be able to give this to the VelocityTracker 616 // directly, or alternatively put a VT into absolute-positioning mode that only 617 // reads the raw screen-coordinate x/y values. 618 private int mNestedYOffset = 0; 619 620 // True when the popup should be hidden because of a call to 621 // dispatchDisplayHint() 622 private boolean mPopupHidden; 623 624 /** 625 * ID of the active pointer. This is used to retain consistency during 626 * drags/flings if multiple pointers are used. 627 */ 628 private int mActivePointerId = INVALID_POINTER; 629 630 /** 631 * Sentinel value for no current active pointer. 632 * Used by {@link #mActivePointerId}. 633 */ 634 private static final int INVALID_POINTER = -1; 635 636 /** 637 * Maximum distance to overscroll by during edge effects 638 */ 639 int mOverscrollDistance; 640 641 /** 642 * Maximum distance to overfling during edge effects 643 */ 644 int mOverflingDistance; 645 646 // These two EdgeGlows are always set and used together. 647 // Checking one for null is as good as checking both. 648 649 /** 650 * Tracks the state of the top edge glow. 651 */ 652 private EdgeEffect mEdgeGlowTop; 653 654 /** 655 * Tracks the state of the bottom edge glow. 656 */ 657 private EdgeEffect mEdgeGlowBottom; 658 659 /** 660 * An estimate of how many pixels are between the top of the list and 661 * the top of the first position in the adapter, based on the last time 662 * we saw it. Used to hint where to draw edge glows. 663 */ 664 private int mFirstPositionDistanceGuess; 665 666 /** 667 * An estimate of how many pixels are between the bottom of the list and 668 * the bottom of the last position in the adapter, based on the last time 669 * we saw it. Used to hint where to draw edge glows. 670 */ 671 private int mLastPositionDistanceGuess; 672 673 /** 674 * Used for determining when to cancel out of overscroll. 675 */ 676 private int mDirection = 0; 677 678 /** 679 * Tracked on measurement in transcript mode. Makes sure that we can still pin to 680 * the bottom correctly on resizes. 681 */ 682 private boolean mForceTranscriptScroll; 683 684 private int mGlowPaddingLeft; 685 private int mGlowPaddingRight; 686 687 /** 688 * Used for interacting with list items from an accessibility service. 689 */ 690 private ListItemAccessibilityDelegate mAccessibilityDelegate; 691 692 private int mLastAccessibilityScrollEventFromIndex; 693 private int mLastAccessibilityScrollEventToIndex; 694 695 /** 696 * Track the item count from the last time we handled a data change. 697 */ 698 private int mLastHandledItemCount; 699 700 /** 701 * Used for smooth scrolling at a consistent rate 702 */ 703 static final Interpolator sLinearInterpolator = new LinearInterpolator(); 704 705 /** 706 * The saved state that we will be restoring from when we next sync. 707 * Kept here so that if we happen to be asked to save our state before 708 * the sync happens, we can return this existing data rather than losing 709 * it. 710 */ 711 private SavedState mPendingSync; 712 713 /** 714 * Whether the view is in the process of detaching from its window. 715 */ 716 private boolean mIsDetaching; 717 718 /** 719 * Interface definition for a callback to be invoked when the list or grid 720 * has been scrolled. 721 */ 722 public interface OnScrollListener { 723 724 /** 725 * The view is not scrolling. Note navigating the list using the trackball counts as 726 * being in the idle state since these transitions are not animated. 727 */ 728 public static int SCROLL_STATE_IDLE = 0; 729 730 /** 731 * The user is scrolling using touch, and their finger is still on the screen 732 */ 733 public static int SCROLL_STATE_TOUCH_SCROLL = 1; 734 735 /** 736 * The user had previously been scrolling using touch and had performed a fling. The 737 * animation is now coasting to a stop 738 */ 739 public static int SCROLL_STATE_FLING = 2; 740 741 /** 742 * Callback method to be invoked while the list view or grid view is being scrolled. If the 743 * view is being scrolled, this method will be called before the next frame of the scroll is 744 * rendered. In particular, it will be called before any calls to 745 * {@link Adapter#getView(int, View, ViewGroup)}. 746 * 747 * @param view The view whose scroll state is being reported 748 * 749 * @param scrollState The current scroll state. One of 750 * {@link #SCROLL_STATE_TOUCH_SCROLL} or {@link #SCROLL_STATE_IDLE}. 751 */ 752 public void onScrollStateChanged(AbsListView view, int scrollState); 753 754 /** 755 * Callback method to be invoked when the list or grid has been scrolled. This will be 756 * called after the scroll has completed 757 * @param view The view whose scroll state is being reported 758 * @param firstVisibleItem the index of the first visible cell (ignore if 759 * visibleItemCount == 0) 760 * @param visibleItemCount the number of visible cells 761 * @param totalItemCount the number of items in the list adaptor 762 */ 763 public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, 764 int totalItemCount); 765 } 766 767 /** 768 * The top-level view of a list item can implement this interface to allow 769 * itself to modify the bounds of the selection shown for that item. 770 */ 771 public interface SelectionBoundsAdjuster { 772 /** 773 * Called to allow the list item to adjust the bounds shown for 774 * its selection. 775 * 776 * @param bounds On call, this contains the bounds the list has 777 * selected for the item (that is the bounds of the entire view). The 778 * values can be modified as desired. 779 */ 780 public void adjustListItemSelectionBounds(Rect bounds); 781 } 782 783 public AbsListView(Context context) { 784 super(context); 785 initAbsListView(); 786 787 mOwnerThread = Thread.currentThread(); 788 789 setVerticalScrollBarEnabled(true); 790 TypedArray a = context.obtainStyledAttributes(R.styleable.View); 791 initializeScrollbarsInternal(a); 792 a.recycle(); 793 } 794 795 public AbsListView(Context context, AttributeSet attrs) { 796 this(context, attrs, com.android.internal.R.attr.absListViewStyle); 797 } 798 799 public AbsListView(Context context, AttributeSet attrs, int defStyleAttr) { 800 this(context, attrs, defStyleAttr, 0); 801 } 802 803 public AbsListView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) { 804 super(context, attrs, defStyleAttr, defStyleRes); 805 initAbsListView(); 806 807 mOwnerThread = Thread.currentThread(); 808 809 final TypedArray a = context.obtainStyledAttributes( 810 attrs, com.android.internal.R.styleable.AbsListView, defStyleAttr, defStyleRes); 811 812 Drawable d = a.getDrawable(com.android.internal.R.styleable.AbsListView_listSelector); 813 if (d != null) { 814 setSelector(d); 815 } 816 817 mDrawSelectorOnTop = a.getBoolean( 818 com.android.internal.R.styleable.AbsListView_drawSelectorOnTop, false); 819 820 boolean stackFromBottom = a.getBoolean(R.styleable.AbsListView_stackFromBottom, false); 821 setStackFromBottom(stackFromBottom); 822 823 boolean scrollingCacheEnabled = a.getBoolean(R.styleable.AbsListView_scrollingCache, true); 824 setScrollingCacheEnabled(scrollingCacheEnabled); 825 826 boolean useTextFilter = a.getBoolean(R.styleable.AbsListView_textFilterEnabled, false); 827 setTextFilterEnabled(useTextFilter); 828 829 int transcriptMode = a.getInt(R.styleable.AbsListView_transcriptMode, 830 TRANSCRIPT_MODE_DISABLED); 831 setTranscriptMode(transcriptMode); 832 833 int color = a.getColor(R.styleable.AbsListView_cacheColorHint, 0); 834 setCacheColorHint(color); 835 836 boolean enableFastScroll = a.getBoolean(R.styleable.AbsListView_fastScrollEnabled, false); 837 setFastScrollEnabled(enableFastScroll); 838 839 int fastScrollStyle = a.getResourceId(R.styleable.AbsListView_fastScrollStyle, 0); 840 setFastScrollStyle(fastScrollStyle); 841 842 boolean smoothScrollbar = a.getBoolean(R.styleable.AbsListView_smoothScrollbar, true); 843 setSmoothScrollbarEnabled(smoothScrollbar); 844 845 setChoiceMode(a.getInt(R.styleable.AbsListView_choiceMode, CHOICE_MODE_NONE)); 846 setFastScrollAlwaysVisible( 847 a.getBoolean(R.styleable.AbsListView_fastScrollAlwaysVisible, false)); 848 849 a.recycle(); 850 } 851 852 private void initAbsListView() { 853 // Setting focusable in touch mode will set the focusable property to true 854 setClickable(true); 855 setFocusableInTouchMode(true); 856 setWillNotDraw(false); 857 setAlwaysDrawnWithCacheEnabled(false); 858 setScrollingCacheEnabled(true); 859 860 final ViewConfiguration configuration = ViewConfiguration.get(mContext); 861 mTouchSlop = configuration.getScaledTouchSlop(); 862 mMinimumVelocity = configuration.getScaledMinimumFlingVelocity(); 863 mMaximumVelocity = configuration.getScaledMaximumFlingVelocity(); 864 mOverscrollDistance = configuration.getScaledOverscrollDistance(); 865 mOverflingDistance = configuration.getScaledOverflingDistance(); 866 867 mDensityScale = getContext().getResources().getDisplayMetrics().density; 868 } 869 870 @Override 871 public void setOverScrollMode(int mode) { 872 if (mode != OVER_SCROLL_NEVER) { 873 if (mEdgeGlowTop == null) { 874 Context context = getContext(); 875 mEdgeGlowTop = new EdgeEffect(context); 876 mEdgeGlowBottom = new EdgeEffect(context); 877 } 878 } else { 879 mEdgeGlowTop = null; 880 mEdgeGlowBottom = null; 881 } 882 super.setOverScrollMode(mode); 883 } 884 885 /** 886 * {@inheritDoc} 887 */ 888 @Override 889 public void setAdapter(ListAdapter adapter) { 890 if (adapter != null) { 891 mAdapterHasStableIds = mAdapter.hasStableIds(); 892 if (mChoiceMode != CHOICE_MODE_NONE && mAdapterHasStableIds && 893 mCheckedIdStates == null) { 894 mCheckedIdStates = new LongSparseArray<Integer>(); 895 } 896 } 897 898 if (mCheckStates != null) { 899 mCheckStates.clear(); 900 } 901 902 if (mCheckedIdStates != null) { 903 mCheckedIdStates.clear(); 904 } 905 } 906 907 /** 908 * Returns the number of items currently selected. This will only be valid 909 * if the choice mode is not {@link #CHOICE_MODE_NONE} (default). 910 * 911 * <p>To determine the specific items that are currently selected, use one of 912 * the <code>getChecked*</code> methods. 913 * 914 * @return The number of items currently selected 915 * 916 * @see #getCheckedItemPosition() 917 * @see #getCheckedItemPositions() 918 * @see #getCheckedItemIds() 919 */ 920 public int getCheckedItemCount() { 921 return mCheckedItemCount; 922 } 923 924 /** 925 * Returns the checked state of the specified position. The result is only 926 * valid if the choice mode has been set to {@link #CHOICE_MODE_SINGLE} 927 * or {@link #CHOICE_MODE_MULTIPLE}. 928 * 929 * @param position The item whose checked state to return 930 * @return The item's checked state or <code>false</code> if choice mode 931 * is invalid 932 * 933 * @see #setChoiceMode(int) 934 */ 935 public boolean isItemChecked(int position) { 936 if (mChoiceMode != CHOICE_MODE_NONE && mCheckStates != null) { 937 return mCheckStates.get(position); 938 } 939 940 return false; 941 } 942 943 /** 944 * Returns the currently checked item. The result is only valid if the choice 945 * mode has been set to {@link #CHOICE_MODE_SINGLE}. 946 * 947 * @return The position of the currently checked item or 948 * {@link #INVALID_POSITION} if nothing is selected 949 * 950 * @see #setChoiceMode(int) 951 */ 952 public int getCheckedItemPosition() { 953 if (mChoiceMode == CHOICE_MODE_SINGLE && mCheckStates != null && mCheckStates.size() == 1) { 954 return mCheckStates.keyAt(0); 955 } 956 957 return INVALID_POSITION; 958 } 959 960 /** 961 * Returns the set of checked items in the list. The result is only valid if 962 * the choice mode has not been set to {@link #CHOICE_MODE_NONE}. 963 * 964 * @return A SparseBooleanArray which will return true for each call to 965 * get(int position) where position is a checked position in the 966 * list and false otherwise, or <code>null</code> if the choice 967 * mode is set to {@link #CHOICE_MODE_NONE}. 968 */ 969 public SparseBooleanArray getCheckedItemPositions() { 970 if (mChoiceMode != CHOICE_MODE_NONE) { 971 return mCheckStates; 972 } 973 return null; 974 } 975 976 /** 977 * Returns the set of checked items ids. The result is only valid if the 978 * choice mode has not been set to {@link #CHOICE_MODE_NONE} and the adapter 979 * has stable IDs. ({@link ListAdapter#hasStableIds()} == {@code true}) 980 * 981 * @return A new array which contains the id of each checked item in the 982 * list. 983 */ 984 public long[] getCheckedItemIds() { 985 if (mChoiceMode == CHOICE_MODE_NONE || mCheckedIdStates == null || mAdapter == null) { 986 return new long[0]; 987 } 988 989 final LongSparseArray<Integer> idStates = mCheckedIdStates; 990 final int count = idStates.size(); 991 final long[] ids = new long[count]; 992 993 for (int i = 0; i < count; i++) { 994 ids[i] = idStates.keyAt(i); 995 } 996 997 return ids; 998 } 999 1000 /** 1001 * Clear any choices previously set 1002 */ 1003 public void clearChoices() { 1004 if (mCheckStates != null) { 1005 mCheckStates.clear(); 1006 } 1007 if (mCheckedIdStates != null) { 1008 mCheckedIdStates.clear(); 1009 } 1010 mCheckedItemCount = 0; 1011 } 1012 1013 /** 1014 * Sets the checked state of the specified position. The is only valid if 1015 * the choice mode has been set to {@link #CHOICE_MODE_SINGLE} or 1016 * {@link #CHOICE_MODE_MULTIPLE}. 1017 * 1018 * @param position The item whose checked state is to be checked 1019 * @param value The new checked state for the item 1020 */ 1021 public void setItemChecked(int position, boolean value) { 1022 if (mChoiceMode == CHOICE_MODE_NONE) { 1023 return; 1024 } 1025 1026 // Start selection mode if needed. We don't need to if we're unchecking something. 1027 if (value && mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL && mChoiceActionMode == null) { 1028 if (mMultiChoiceModeCallback == null || 1029 !mMultiChoiceModeCallback.hasWrappedCallback()) { 1030 throw new IllegalStateException("AbsListView: attempted to start selection mode " + 1031 "for CHOICE_MODE_MULTIPLE_MODAL but no choice mode callback was " + 1032 "supplied. Call setMultiChoiceModeListener to set a callback."); 1033 } 1034 mChoiceActionMode = startActionMode(mMultiChoiceModeCallback); 1035 } 1036 1037 if (mChoiceMode == CHOICE_MODE_MULTIPLE || mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL) { 1038 boolean oldValue = mCheckStates.get(position); 1039 mCheckStates.put(position, value); 1040 if (mCheckedIdStates != null && mAdapter.hasStableIds()) { 1041 if (value) { 1042 mCheckedIdStates.put(mAdapter.getItemId(position), position); 1043 } else { 1044 mCheckedIdStates.delete(mAdapter.getItemId(position)); 1045 } 1046 } 1047 if (oldValue != value) { 1048 if (value) { 1049 mCheckedItemCount++; 1050 } else { 1051 mCheckedItemCount--; 1052 } 1053 } 1054 if (mChoiceActionMode != null) { 1055 final long id = mAdapter.getItemId(position); 1056 mMultiChoiceModeCallback.onItemCheckedStateChanged(mChoiceActionMode, 1057 position, id, value); 1058 } 1059 } else { 1060 boolean updateIds = mCheckedIdStates != null && mAdapter.hasStableIds(); 1061 // Clear all values if we're checking something, or unchecking the currently 1062 // selected item 1063 if (value || isItemChecked(position)) { 1064 mCheckStates.clear(); 1065 if (updateIds) { 1066 mCheckedIdStates.clear(); 1067 } 1068 } 1069 // this may end up selecting the value we just cleared but this way 1070 // we ensure length of mCheckStates is 1, a fact getCheckedItemPosition relies on 1071 if (value) { 1072 mCheckStates.put(position, true); 1073 if (updateIds) { 1074 mCheckedIdStates.put(mAdapter.getItemId(position), position); 1075 } 1076 mCheckedItemCount = 1; 1077 } else if (mCheckStates.size() == 0 || !mCheckStates.valueAt(0)) { 1078 mCheckedItemCount = 0; 1079 } 1080 } 1081 1082 // Do not generate a data change while we are in the layout phase 1083 if (!mInLayout && !mBlockLayoutRequests) { 1084 mDataChanged = true; 1085 rememberSyncState(); 1086 requestLayout(); 1087 } 1088 } 1089 1090 @Override 1091 public boolean performItemClick(View view, int position, long id) { 1092 boolean handled = false; 1093 boolean dispatchItemClick = true; 1094 1095 if (mChoiceMode != CHOICE_MODE_NONE) { 1096 handled = true; 1097 boolean checkedStateChanged = false; 1098 1099 if (mChoiceMode == CHOICE_MODE_MULTIPLE || 1100 (mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL && mChoiceActionMode != null)) { 1101 boolean checked = !mCheckStates.get(position, false); 1102 mCheckStates.put(position, checked); 1103 if (mCheckedIdStates != null && mAdapter.hasStableIds()) { 1104 if (checked) { 1105 mCheckedIdStates.put(mAdapter.getItemId(position), position); 1106 } else { 1107 mCheckedIdStates.delete(mAdapter.getItemId(position)); 1108 } 1109 } 1110 if (checked) { 1111 mCheckedItemCount++; 1112 } else { 1113 mCheckedItemCount--; 1114 } 1115 if (mChoiceActionMode != null) { 1116 mMultiChoiceModeCallback.onItemCheckedStateChanged(mChoiceActionMode, 1117 position, id, checked); 1118 dispatchItemClick = false; 1119 } 1120 checkedStateChanged = true; 1121 } else if (mChoiceMode == CHOICE_MODE_SINGLE) { 1122 boolean checked = !mCheckStates.get(position, false); 1123 if (checked) { 1124 mCheckStates.clear(); 1125 mCheckStates.put(position, true); 1126 if (mCheckedIdStates != null && mAdapter.hasStableIds()) { 1127 mCheckedIdStates.clear(); 1128 mCheckedIdStates.put(mAdapter.getItemId(position), position); 1129 } 1130 mCheckedItemCount = 1; 1131 } else if (mCheckStates.size() == 0 || !mCheckStates.valueAt(0)) { 1132 mCheckedItemCount = 0; 1133 } 1134 checkedStateChanged = true; 1135 } 1136 1137 if (checkedStateChanged) { 1138 updateOnScreenCheckedViews(); 1139 } 1140 } 1141 1142 if (dispatchItemClick) { 1143 handled |= super.performItemClick(view, position, id); 1144 } 1145 1146 return handled; 1147 } 1148 1149 /** 1150 * Perform a quick, in-place update of the checked or activated state 1151 * on all visible item views. This should only be called when a valid 1152 * choice mode is active. 1153 */ 1154 private void updateOnScreenCheckedViews() { 1155 final int firstPos = mFirstPosition; 1156 final int count = getChildCount(); 1157 final boolean useActivated = getContext().getApplicationInfo().targetSdkVersion 1158 >= android.os.Build.VERSION_CODES.HONEYCOMB; 1159 for (int i = 0; i < count; i++) { 1160 final View child = getChildAt(i); 1161 final int position = firstPos + i; 1162 1163 if (child instanceof Checkable) { 1164 ((Checkable) child).setChecked(mCheckStates.get(position)); 1165 } else if (useActivated) { 1166 child.setActivated(mCheckStates.get(position)); 1167 } 1168 } 1169 } 1170 1171 /** 1172 * @see #setChoiceMode(int) 1173 * 1174 * @return The current choice mode 1175 */ 1176 public int getChoiceMode() { 1177 return mChoiceMode; 1178 } 1179 1180 /** 1181 * Defines the choice behavior for the List. By default, Lists do not have any choice behavior 1182 * ({@link #CHOICE_MODE_NONE}). By setting the choiceMode to {@link #CHOICE_MODE_SINGLE}, the 1183 * List allows up to one item to be in a chosen state. By setting the choiceMode to 1184 * {@link #CHOICE_MODE_MULTIPLE}, the list allows any number of items to be chosen. 1185 * 1186 * @param choiceMode One of {@link #CHOICE_MODE_NONE}, {@link #CHOICE_MODE_SINGLE}, or 1187 * {@link #CHOICE_MODE_MULTIPLE} 1188 */ 1189 public void setChoiceMode(int choiceMode) { 1190 mChoiceMode = choiceMode; 1191 if (mChoiceActionMode != null) { 1192 mChoiceActionMode.finish(); 1193 mChoiceActionMode = null; 1194 } 1195 if (mChoiceMode != CHOICE_MODE_NONE) { 1196 if (mCheckStates == null) { 1197 mCheckStates = new SparseBooleanArray(0); 1198 } 1199 if (mCheckedIdStates == null && mAdapter != null && mAdapter.hasStableIds()) { 1200 mCheckedIdStates = new LongSparseArray<Integer>(0); 1201 } 1202 // Modal multi-choice mode only has choices when the mode is active. Clear them. 1203 if (mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL) { 1204 clearChoices(); 1205 setLongClickable(true); 1206 } 1207 } 1208 } 1209 1210 /** 1211 * Set a {@link MultiChoiceModeListener} that will manage the lifecycle of the 1212 * selection {@link ActionMode}. Only used when the choice mode is set to 1213 * {@link #CHOICE_MODE_MULTIPLE_MODAL}. 1214 * 1215 * @param listener Listener that will manage the selection mode 1216 * 1217 * @see #setChoiceMode(int) 1218 */ 1219 public void setMultiChoiceModeListener(MultiChoiceModeListener listener) { 1220 if (mMultiChoiceModeCallback == null) { 1221 mMultiChoiceModeCallback = new MultiChoiceModeWrapper(); 1222 } 1223 mMultiChoiceModeCallback.setWrapped(listener); 1224 } 1225 1226 /** 1227 * @return true if all list content currently fits within the view boundaries 1228 */ 1229 private boolean contentFits() { 1230 final int childCount = getChildCount(); 1231 if (childCount == 0) return true; 1232 if (childCount != mItemCount) return false; 1233 1234 return getChildAt(0).getTop() >= mListPadding.top && 1235 getChildAt(childCount - 1).getBottom() <= getHeight() - mListPadding.bottom; 1236 } 1237 1238 /** 1239 * Specifies whether fast scrolling is enabled or disabled. 1240 * <p> 1241 * When fast scrolling is enabled, the user can quickly scroll through lists 1242 * by dragging the fast scroll thumb. 1243 * <p> 1244 * If the adapter backing this list implements {@link SectionIndexer}, the 1245 * fast scroller will display section header previews as the user scrolls. 1246 * Additionally, the user will be able to quickly jump between sections by 1247 * tapping along the length of the scroll bar. 1248 * 1249 * @see SectionIndexer 1250 * @see #isFastScrollEnabled() 1251 * @param enabled true to enable fast scrolling, false otherwise 1252 */ 1253 public void setFastScrollEnabled(final boolean enabled) { 1254 if (mFastScrollEnabled != enabled) { 1255 mFastScrollEnabled = enabled; 1256 1257 if (isOwnerThread()) { 1258 setFastScrollerEnabledUiThread(enabled); 1259 } else { 1260 post(new Runnable() { 1261 @Override 1262 public void run() { 1263 setFastScrollerEnabledUiThread(enabled); 1264 } 1265 }); 1266 } 1267 } 1268 } 1269 1270 private void setFastScrollerEnabledUiThread(boolean enabled) { 1271 if (mFastScroll != null) { 1272 mFastScroll.setEnabled(enabled); 1273 } else if (enabled) { 1274 mFastScroll = new FastScroller(this, mFastScrollStyle); 1275 mFastScroll.setEnabled(true); 1276 } 1277 1278 resolvePadding(); 1279 1280 if (mFastScroll != null) { 1281 mFastScroll.updateLayout(); 1282 } 1283 } 1284 1285 /** 1286 * Specifies the style of the fast scroller decorations. 1287 * 1288 * @param styleResId style resource containing fast scroller properties 1289 * @see android.R.styleable#FastScroll 1290 */ 1291 public void setFastScrollStyle(int styleResId) { 1292 if (mFastScroll == null) { 1293 mFastScrollStyle = styleResId; 1294 } else { 1295 mFastScroll.setStyle(styleResId); 1296 } 1297 } 1298 1299 /** 1300 * Set whether or not the fast scroller should always be shown in place of 1301 * the standard scroll bars. This will enable fast scrolling if it is not 1302 * already enabled. 1303 * <p> 1304 * Fast scrollers shown in this way will not fade out and will be a 1305 * permanent fixture within the list. This is best combined with an inset 1306 * scroll bar style to ensure the scroll bar does not overlap content. 1307 * 1308 * @param alwaysShow true if the fast scroller should always be displayed, 1309 * false otherwise 1310 * @see #setScrollBarStyle(int) 1311 * @see #setFastScrollEnabled(boolean) 1312 */ 1313 public void setFastScrollAlwaysVisible(final boolean alwaysShow) { 1314 if (mFastScrollAlwaysVisible != alwaysShow) { 1315 if (alwaysShow && !mFastScrollEnabled) { 1316 setFastScrollEnabled(true); 1317 } 1318 1319 mFastScrollAlwaysVisible = alwaysShow; 1320 1321 if (isOwnerThread()) { 1322 setFastScrollerAlwaysVisibleUiThread(alwaysShow); 1323 } else { 1324 post(new Runnable() { 1325 @Override 1326 public void run() { 1327 setFastScrollerAlwaysVisibleUiThread(alwaysShow); 1328 } 1329 }); 1330 } 1331 } 1332 } 1333 1334 private void setFastScrollerAlwaysVisibleUiThread(boolean alwaysShow) { 1335 if (mFastScroll != null) { 1336 mFastScroll.setAlwaysShow(alwaysShow); 1337 } 1338 } 1339 1340 /** 1341 * @return whether the current thread is the one that created the view 1342 */ 1343 private boolean isOwnerThread() { 1344 return mOwnerThread == Thread.currentThread(); 1345 } 1346 1347 /** 1348 * Returns true if the fast scroller is set to always show on this view. 1349 * 1350 * @return true if the fast scroller will always show 1351 * @see #setFastScrollAlwaysVisible(boolean) 1352 */ 1353 public boolean isFastScrollAlwaysVisible() { 1354 if (mFastScroll == null) { 1355 return mFastScrollEnabled && mFastScrollAlwaysVisible; 1356 } else { 1357 return mFastScroll.isEnabled() && mFastScroll.isAlwaysShowEnabled(); 1358 } 1359 } 1360 1361 @Override 1362 public int getVerticalScrollbarWidth() { 1363 if (mFastScroll != null && mFastScroll.isEnabled()) { 1364 return Math.max(super.getVerticalScrollbarWidth(), mFastScroll.getWidth()); 1365 } 1366 return super.getVerticalScrollbarWidth(); 1367 } 1368 1369 /** 1370 * Returns true if the fast scroller is enabled. 1371 * 1372 * @see #setFastScrollEnabled(boolean) 1373 * @return true if fast scroll is enabled, false otherwise 1374 */ 1375 @ViewDebug.ExportedProperty 1376 public boolean isFastScrollEnabled() { 1377 if (mFastScroll == null) { 1378 return mFastScrollEnabled; 1379 } else { 1380 return mFastScroll.isEnabled(); 1381 } 1382 } 1383 1384 @Override 1385 public void setVerticalScrollbarPosition(int position) { 1386 super.setVerticalScrollbarPosition(position); 1387 if (mFastScroll != null) { 1388 mFastScroll.setScrollbarPosition(position); 1389 } 1390 } 1391 1392 @Override 1393 public void setScrollBarStyle(int style) { 1394 super.setScrollBarStyle(style); 1395 if (mFastScroll != null) { 1396 mFastScroll.setScrollBarStyle(style); 1397 } 1398 } 1399 1400 /** 1401 * If fast scroll is enabled, then don't draw the vertical scrollbar. 1402 * @hide 1403 */ 1404 @Override 1405 protected boolean isVerticalScrollBarHidden() { 1406 return isFastScrollEnabled(); 1407 } 1408 1409 /** 1410 * When smooth scrollbar is enabled, the position and size of the scrollbar thumb 1411 * is computed based on the number of visible pixels in the visible items. This 1412 * however assumes that all list items have the same height. If you use a list in 1413 * which items have different heights, the scrollbar will change appearance as the 1414 * user scrolls through the list. To avoid this issue, you need to disable this 1415 * property. 1416 * 1417 * When smooth scrollbar is disabled, the position and size of the scrollbar thumb 1418 * is based solely on the number of items in the adapter and the position of the 1419 * visible items inside the adapter. This provides a stable scrollbar as the user 1420 * navigates through a list of items with varying heights. 1421 * 1422 * @param enabled Whether or not to enable smooth scrollbar. 1423 * 1424 * @see #setSmoothScrollbarEnabled(boolean) 1425 * @attr ref android.R.styleable#AbsListView_smoothScrollbar 1426 */ 1427 public void setSmoothScrollbarEnabled(boolean enabled) { 1428 mSmoothScrollbarEnabled = enabled; 1429 } 1430 1431 /** 1432 * Returns the current state of the fast scroll feature. 1433 * 1434 * @return True if smooth scrollbar is enabled is enabled, false otherwise. 1435 * 1436 * @see #setSmoothScrollbarEnabled(boolean) 1437 */ 1438 @ViewDebug.ExportedProperty 1439 public boolean isSmoothScrollbarEnabled() { 1440 return mSmoothScrollbarEnabled; 1441 } 1442 1443 /** 1444 * Set the listener that will receive notifications every time the list scrolls. 1445 * 1446 * @param l the scroll listener 1447 */ 1448 public void setOnScrollListener(OnScrollListener l) { 1449 mOnScrollListener = l; 1450 invokeOnItemScrollListener(); 1451 } 1452 1453 /** 1454 * Notify our scroll listener (if there is one) of a change in scroll state 1455 */ 1456 void invokeOnItemScrollListener() { 1457 if (mFastScroll != null) { 1458 mFastScroll.onScroll(mFirstPosition, getChildCount(), mItemCount); 1459 } 1460 if (mOnScrollListener != null) { 1461 mOnScrollListener.onScroll(this, mFirstPosition, getChildCount(), mItemCount); 1462 } 1463 onScrollChanged(0, 0, 0, 0); // dummy values, View's implementation does not use these. 1464 } 1465 1466 @Override 1467 public void sendAccessibilityEvent(int eventType) { 1468 // Since this class calls onScrollChanged even if the mFirstPosition and the 1469 // child count have not changed we will avoid sending duplicate accessibility 1470 // events. 1471 if (eventType == AccessibilityEvent.TYPE_VIEW_SCROLLED) { 1472 final int firstVisiblePosition = getFirstVisiblePosition(); 1473 final int lastVisiblePosition = getLastVisiblePosition(); 1474 if (mLastAccessibilityScrollEventFromIndex == firstVisiblePosition 1475 && mLastAccessibilityScrollEventToIndex == lastVisiblePosition) { 1476 return; 1477 } else { 1478 mLastAccessibilityScrollEventFromIndex = firstVisiblePosition; 1479 mLastAccessibilityScrollEventToIndex = lastVisiblePosition; 1480 } 1481 } 1482 super.sendAccessibilityEvent(eventType); 1483 } 1484 1485 @Override 1486 public void onInitializeAccessibilityEvent(AccessibilityEvent event) { 1487 super.onInitializeAccessibilityEvent(event); 1488 event.setClassName(AbsListView.class.getName()); 1489 } 1490 1491 @Override 1492 public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) { 1493 super.onInitializeAccessibilityNodeInfo(info); 1494 info.setClassName(AbsListView.class.getName()); 1495 if (isEnabled()) { 1496 if (canScrollUp()) { 1497 info.addAction(AccessibilityNodeInfo.ACTION_SCROLL_BACKWARD); 1498 info.setScrollable(true); 1499 } 1500 if (canScrollDown()) { 1501 info.addAction(AccessibilityNodeInfo.ACTION_SCROLL_FORWARD); 1502 info.setScrollable(true); 1503 } 1504 } 1505 } 1506 1507 int getSelectionModeForAccessibility() { 1508 final int choiceMode = getChoiceMode(); 1509 switch (choiceMode) { 1510 case CHOICE_MODE_NONE: 1511 return CollectionInfo.SELECTION_MODE_NONE; 1512 case CHOICE_MODE_SINGLE: 1513 return CollectionInfo.SELECTION_MODE_SINGLE; 1514 case CHOICE_MODE_MULTIPLE: 1515 case CHOICE_MODE_MULTIPLE_MODAL: 1516 return CollectionInfo.SELECTION_MODE_MULTIPLE; 1517 default: 1518 return CollectionInfo.SELECTION_MODE_NONE; 1519 } 1520 } 1521 1522 @Override 1523 public boolean performAccessibilityAction(int action, Bundle arguments) { 1524 if (super.performAccessibilityAction(action, arguments)) { 1525 return true; 1526 } 1527 switch (action) { 1528 case AccessibilityNodeInfo.ACTION_SCROLL_FORWARD: { 1529 if (isEnabled() && getLastVisiblePosition() < getCount() - 1) { 1530 final int viewportHeight = getHeight() - mListPadding.top - mListPadding.bottom; 1531 smoothScrollBy(viewportHeight, PositionScroller.SCROLL_DURATION); 1532 return true; 1533 } 1534 } return false; 1535 case AccessibilityNodeInfo.ACTION_SCROLL_BACKWARD: { 1536 if (isEnabled() && mFirstPosition > 0) { 1537 final int viewportHeight = getHeight() - mListPadding.top - mListPadding.bottom; 1538 smoothScrollBy(-viewportHeight, PositionScroller.SCROLL_DURATION); 1539 return true; 1540 } 1541 } return false; 1542 } 1543 return false; 1544 } 1545 1546 /** @hide */ 1547 @Override 1548 public View findViewByAccessibilityIdTraversal(int accessibilityId) { 1549 if (accessibilityId == getAccessibilityViewId()) { 1550 return this; 1551 } 1552 // If the data changed the children are invalid since the data model changed. 1553 // Hence, we pretend they do not exist. After a layout the children will sync 1554 // with the model at which point we notify that the accessibility state changed, 1555 // so a service will be able to re-fetch the views. 1556 if (mDataChanged) { 1557 return null; 1558 } 1559 return super.findViewByAccessibilityIdTraversal(accessibilityId); 1560 } 1561 1562 /** 1563 * Indicates whether the children's drawing cache is used during a scroll. 1564 * By default, the drawing cache is enabled but this will consume more memory. 1565 * 1566 * @return true if the scrolling cache is enabled, false otherwise 1567 * 1568 * @see #setScrollingCacheEnabled(boolean) 1569 * @see View#setDrawingCacheEnabled(boolean) 1570 */ 1571 @ViewDebug.ExportedProperty 1572 public boolean isScrollingCacheEnabled() { 1573 return mScrollingCacheEnabled; 1574 } 1575 1576 /** 1577 * Enables or disables the children's drawing cache during a scroll. 1578 * By default, the drawing cache is enabled but this will use more memory. 1579 * 1580 * When the scrolling cache is enabled, the caches are kept after the 1581 * first scrolling. You can manually clear the cache by calling 1582 * {@link android.view.ViewGroup#setChildrenDrawingCacheEnabled(boolean)}. 1583 * 1584 * @param enabled true to enable the scroll cache, false otherwise 1585 * 1586 * @see #isScrollingCacheEnabled() 1587 * @see View#setDrawingCacheEnabled(boolean) 1588 */ 1589 public void setScrollingCacheEnabled(boolean enabled) { 1590 if (mScrollingCacheEnabled && !enabled) { 1591 clearScrollingCache(); 1592 } 1593 mScrollingCacheEnabled = enabled; 1594 } 1595 1596 /** 1597 * Enables or disables the type filter window. If enabled, typing when 1598 * this view has focus will filter the children to match the users input. 1599 * Note that the {@link Adapter} used by this view must implement the 1600 * {@link Filterable} interface. 1601 * 1602 * @param textFilterEnabled true to enable type filtering, false otherwise 1603 * 1604 * @see Filterable 1605 */ 1606 public void setTextFilterEnabled(boolean textFilterEnabled) { 1607 mTextFilterEnabled = textFilterEnabled; 1608 } 1609 1610 /** 1611 * Indicates whether type filtering is enabled for this view 1612 * 1613 * @return true if type filtering is enabled, false otherwise 1614 * 1615 * @see #setTextFilterEnabled(boolean) 1616 * @see Filterable 1617 */ 1618 @ViewDebug.ExportedProperty 1619 public boolean isTextFilterEnabled() { 1620 return mTextFilterEnabled; 1621 } 1622 1623 @Override 1624 public void getFocusedRect(Rect r) { 1625 View view = getSelectedView(); 1626 if (view != null && view.getParent() == this) { 1627 // the focused rectangle of the selected view offset into the 1628 // coordinate space of this view. 1629 view.getFocusedRect(r); 1630 offsetDescendantRectToMyCoords(view, r); 1631 } else { 1632 // otherwise, just the norm 1633 super.getFocusedRect(r); 1634 } 1635 } 1636 1637 private void useDefaultSelector() { 1638 setSelector(getContext().getDrawable( 1639 com.android.internal.R.drawable.list_selector_background)); 1640 } 1641 1642 /** 1643 * Indicates whether the content of this view is pinned to, or stacked from, 1644 * the bottom edge. 1645 * 1646 * @return true if the content is stacked from the bottom edge, false otherwise 1647 */ 1648 @ViewDebug.ExportedProperty 1649 public boolean isStackFromBottom() { 1650 return mStackFromBottom; 1651 } 1652 1653 /** 1654 * When stack from bottom is set to true, the list fills its content starting from 1655 * the bottom of the view. 1656 * 1657 * @param stackFromBottom true to pin the view's content to the bottom edge, 1658 * false to pin the view's content to the top edge 1659 */ 1660 public void setStackFromBottom(boolean stackFromBottom) { 1661 if (mStackFromBottom != stackFromBottom) { 1662 mStackFromBottom = stackFromBottom; 1663 requestLayoutIfNecessary(); 1664 } 1665 } 1666 1667 void requestLayoutIfNecessary() { 1668 if (getChildCount() > 0) { 1669 resetList(); 1670 requestLayout(); 1671 invalidate(); 1672 } 1673 } 1674 1675 static class SavedState extends BaseSavedState { 1676 long selectedId; 1677 long firstId; 1678 int viewTop; 1679 int position; 1680 int height; 1681 String filter; 1682 boolean inActionMode; 1683 int checkedItemCount; 1684 SparseBooleanArray checkState; 1685 LongSparseArray<Integer> checkIdState; 1686 1687 /** 1688 * Constructor called from {@link AbsListView#onSaveInstanceState()} 1689 */ 1690 SavedState(Parcelable superState) { 1691 super(superState); 1692 } 1693 1694 /** 1695 * Constructor called from {@link #CREATOR} 1696 */ 1697 private SavedState(Parcel in) { 1698 super(in); 1699 selectedId = in.readLong(); 1700 firstId = in.readLong(); 1701 viewTop = in.readInt(); 1702 position = in.readInt(); 1703 height = in.readInt(); 1704 filter = in.readString(); 1705 inActionMode = in.readByte() != 0; 1706 checkedItemCount = in.readInt(); 1707 checkState = in.readSparseBooleanArray(); 1708 final int N = in.readInt(); 1709 if (N > 0) { 1710 checkIdState = new LongSparseArray<Integer>(); 1711 for (int i=0; i<N; i++) { 1712 final long key = in.readLong(); 1713 final int value = in.readInt(); 1714 checkIdState.put(key, value); 1715 } 1716 } 1717 } 1718 1719 @Override 1720 public void writeToParcel(Parcel out, int flags) { 1721 super.writeToParcel(out, flags); 1722 out.writeLong(selectedId); 1723 out.writeLong(firstId); 1724 out.writeInt(viewTop); 1725 out.writeInt(position); 1726 out.writeInt(height); 1727 out.writeString(filter); 1728 out.writeByte((byte) (inActionMode ? 1 : 0)); 1729 out.writeInt(checkedItemCount); 1730 out.writeSparseBooleanArray(checkState); 1731 final int N = checkIdState != null ? checkIdState.size() : 0; 1732 out.writeInt(N); 1733 for (int i=0; i<N; i++) { 1734 out.writeLong(checkIdState.keyAt(i)); 1735 out.writeInt(checkIdState.valueAt(i)); 1736 } 1737 } 1738 1739 @Override 1740 public String toString() { 1741 return "AbsListView.SavedState{" 1742 + Integer.toHexString(System.identityHashCode(this)) 1743 + " selectedId=" + selectedId 1744 + " firstId=" + firstId 1745 + " viewTop=" + viewTop 1746 + " position=" + position 1747 + " height=" + height 1748 + " filter=" + filter 1749 + " checkState=" + checkState + "}"; 1750 } 1751 1752 public static final Parcelable.Creator<SavedState> CREATOR 1753 = new Parcelable.Creator<SavedState>() { 1754 @Override 1755 public SavedState createFromParcel(Parcel in) { 1756 return new SavedState(in); 1757 } 1758 1759 @Override 1760 public SavedState[] newArray(int size) { 1761 return new SavedState[size]; 1762 } 1763 }; 1764 } 1765 1766 @Override 1767 public Parcelable onSaveInstanceState() { 1768 /* 1769 * This doesn't really make sense as the place to dismiss the 1770 * popups, but there don't seem to be any other useful hooks 1771 * that happen early enough to keep from getting complaints 1772 * about having leaked the window. 1773 */ 1774 dismissPopup(); 1775 1776 Parcelable superState = super.onSaveInstanceState(); 1777 1778 SavedState ss = new SavedState(superState); 1779 1780 if (mPendingSync != null) { 1781 // Just keep what we last restored. 1782 ss.selectedId = mPendingSync.selectedId; 1783 ss.firstId = mPendingSync.firstId; 1784 ss.viewTop = mPendingSync.viewTop; 1785 ss.position = mPendingSync.position; 1786 ss.height = mPendingSync.height; 1787 ss.filter = mPendingSync.filter; 1788 ss.inActionMode = mPendingSync.inActionMode; 1789 ss.checkedItemCount = mPendingSync.checkedItemCount; 1790 ss.checkState = mPendingSync.checkState; 1791 ss.checkIdState = mPendingSync.checkIdState; 1792 return ss; 1793 } 1794 1795 boolean haveChildren = getChildCount() > 0 && mItemCount > 0; 1796 long selectedId = getSelectedItemId(); 1797 ss.selectedId = selectedId; 1798 ss.height = getHeight(); 1799 1800 if (selectedId >= 0) { 1801 // Remember the selection 1802 ss.viewTop = mSelectedTop; 1803 ss.position = getSelectedItemPosition(); 1804 ss.firstId = INVALID_POSITION; 1805 } else { 1806 if (haveChildren && mFirstPosition > 0) { 1807 // Remember the position of the first child. 1808 // We only do this if we are not currently at the top of 1809 // the list, for two reasons: 1810 // (1) The list may be in the process of becoming empty, in 1811 // which case mItemCount may not be 0, but if we try to 1812 // ask for any information about position 0 we will crash. 1813 // (2) Being "at the top" seems like a special case, anyway, 1814 // and the user wouldn't expect to end up somewhere else when 1815 // they revisit the list even if its content has changed. 1816 View v = getChildAt(0); 1817 ss.viewTop = v.getTop(); 1818 int firstPos = mFirstPosition; 1819 if (firstPos >= mItemCount) { 1820 firstPos = mItemCount - 1; 1821 } 1822 ss.position = firstPos; 1823 ss.firstId = mAdapter.getItemId(firstPos); 1824 } else { 1825 ss.viewTop = 0; 1826 ss.firstId = INVALID_POSITION; 1827 ss.position = 0; 1828 } 1829 } 1830 1831 ss.filter = null; 1832 if (mFiltered) { 1833 final EditText textFilter = mTextFilter; 1834 if (textFilter != null) { 1835 Editable filterText = textFilter.getText(); 1836 if (filterText != null) { 1837 ss.filter = filterText.toString(); 1838 } 1839 } 1840 } 1841 1842 ss.inActionMode = mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL && mChoiceActionMode != null; 1843 1844 if (mCheckStates != null) { 1845 ss.checkState = mCheckStates.clone(); 1846 } 1847 if (mCheckedIdStates != null) { 1848 final LongSparseArray<Integer> idState = new LongSparseArray<Integer>(); 1849 final int count = mCheckedIdStates.size(); 1850 for (int i = 0; i < count; i++) { 1851 idState.put(mCheckedIdStates.keyAt(i), mCheckedIdStates.valueAt(i)); 1852 } 1853 ss.checkIdState = idState; 1854 } 1855 ss.checkedItemCount = mCheckedItemCount; 1856 1857 if (mRemoteAdapter != null) { 1858 mRemoteAdapter.saveRemoteViewsCache(); 1859 } 1860 1861 return ss; 1862 } 1863 1864 @Override 1865 public void onRestoreInstanceState(Parcelable state) { 1866 SavedState ss = (SavedState) state; 1867 1868 super.onRestoreInstanceState(ss.getSuperState()); 1869 mDataChanged = true; 1870 1871 mSyncHeight = ss.height; 1872 1873 if (ss.selectedId >= 0) { 1874 mNeedSync = true; 1875 mPendingSync = ss; 1876 mSyncRowId = ss.selectedId; 1877 mSyncPosition = ss.position; 1878 mSpecificTop = ss.viewTop; 1879 mSyncMode = SYNC_SELECTED_POSITION; 1880 } else if (ss.firstId >= 0) { 1881 setSelectedPositionInt(INVALID_POSITION); 1882 // Do this before setting mNeedSync since setNextSelectedPosition looks at mNeedSync 1883 setNextSelectedPositionInt(INVALID_POSITION); 1884 mSelectorPosition = INVALID_POSITION; 1885 mNeedSync = true; 1886 mPendingSync = ss; 1887 mSyncRowId = ss.firstId; 1888 mSyncPosition = ss.position; 1889 mSpecificTop = ss.viewTop; 1890 mSyncMode = SYNC_FIRST_POSITION; 1891 } 1892 1893 setFilterText(ss.filter); 1894 1895 if (ss.checkState != null) { 1896 mCheckStates = ss.checkState; 1897 } 1898 1899 if (ss.checkIdState != null) { 1900 mCheckedIdStates = ss.checkIdState; 1901 } 1902 1903 mCheckedItemCount = ss.checkedItemCount; 1904 1905 if (ss.inActionMode && mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL && 1906 mMultiChoiceModeCallback != null) { 1907 mChoiceActionMode = startActionMode(mMultiChoiceModeCallback); 1908 } 1909 1910 requestLayout(); 1911 } 1912 1913 private boolean acceptFilter() { 1914 return mTextFilterEnabled && getAdapter() instanceof Filterable && 1915 ((Filterable) getAdapter()).getFilter() != null; 1916 } 1917 1918 /** 1919 * Sets the initial value for the text filter. 1920 * @param filterText The text to use for the filter. 1921 * 1922 * @see #setTextFilterEnabled 1923 */ 1924 public void setFilterText(String filterText) { 1925 // TODO: Should we check for acceptFilter()? 1926 if (mTextFilterEnabled && !TextUtils.isEmpty(filterText)) { 1927 createTextFilter(false); 1928 // This is going to call our listener onTextChanged, but we might not 1929 // be ready to bring up a window yet 1930 mTextFilter.setText(filterText); 1931 mTextFilter.setSelection(filterText.length()); 1932 if (mAdapter instanceof Filterable) { 1933 // if mPopup is non-null, then onTextChanged will do the filtering 1934 if (mPopup == null) { 1935 Filter f = ((Filterable) mAdapter).getFilter(); 1936 f.filter(filterText); 1937 } 1938 // Set filtered to true so we will display the filter window when our main 1939 // window is ready 1940 mFiltered = true; 1941 mDataSetObserver.clearSavedState(); 1942 } 1943 } 1944 } 1945 1946 /** 1947 * Returns the list's text filter, if available. 1948 * @return the list's text filter or null if filtering isn't enabled 1949 */ 1950 public CharSequence getTextFilter() { 1951 if (mTextFilterEnabled && mTextFilter != null) { 1952 return mTextFilter.getText(); 1953 } 1954 return null; 1955 } 1956 1957 @Override 1958 protected void onFocusChanged(boolean gainFocus, int direction, Rect previouslyFocusedRect) { 1959 super.onFocusChanged(gainFocus, direction, previouslyFocusedRect); 1960 if (gainFocus && mSelectedPosition < 0 && !isInTouchMode()) { 1961 if (!isAttachedToWindow() && mAdapter != null) { 1962 // Data may have changed while we were detached and it's valid 1963 // to change focus while detached. Refresh so we don't die. 1964 mDataChanged = true; 1965 mOldItemCount = mItemCount; 1966 mItemCount = mAdapter.getCount(); 1967 } 1968 resurrectSelection(); 1969 } 1970 } 1971 1972 @Override 1973 public void requestLayout() { 1974 if (!mBlockLayoutRequests && !mInLayout) { 1975 super.requestLayout(); 1976 } 1977 } 1978 1979 /** 1980 * The list is empty. Clear everything out. 1981 */ 1982 void resetList() { 1983 removeAllViewsInLayout(); 1984 mFirstPosition = 0; 1985 mDataChanged = false; 1986 mPositionScrollAfterLayout = null; 1987 mNeedSync = false; 1988 mPendingSync = null; 1989 mOldSelectedPosition = INVALID_POSITION; 1990 mOldSelectedRowId = INVALID_ROW_ID; 1991 setSelectedPositionInt(INVALID_POSITION); 1992 setNextSelectedPositionInt(INVALID_POSITION); 1993 mSelectedTop = 0; 1994 mSelectorPosition = INVALID_POSITION; 1995 mSelectorRect.setEmpty(); 1996 invalidate(); 1997 } 1998 1999 @Override 2000 protected int computeVerticalScrollExtent() { 2001 final int count = getChildCount(); 2002 if (count > 0) { 2003 if (mSmoothScrollbarEnabled) { 2004 int extent = count * 100; 2005 2006 View view = getChildAt(0); 2007 final int top = view.getTop(); 2008 int height = view.getHeight(); 2009 if (height > 0) { 2010 extent += (top * 100) / height; 2011 } 2012 2013 view = getChildAt(count - 1); 2014 final int bottom = view.getBottom(); 2015 height = view.getHeight(); 2016 if (height > 0) { 2017 extent -= ((bottom - getHeight()) * 100) / height; 2018 } 2019 2020 return extent; 2021 } else { 2022 return 1; 2023 } 2024 } 2025 return 0; 2026 } 2027 2028 @Override 2029 protected int computeVerticalScrollOffset() { 2030 final int firstPosition = mFirstPosition; 2031 final int childCount = getChildCount(); 2032 if (firstPosition >= 0 && childCount > 0) { 2033 if (mSmoothScrollbarEnabled) { 2034 final View view = getChildAt(0); 2035 final int top = view.getTop(); 2036 int height = view.getHeight(); 2037 if (height > 0) { 2038 return Math.max(firstPosition * 100 - (top * 100) / height + 2039 (int)((float)mScrollY / getHeight() * mItemCount * 100), 0); 2040 } 2041 } else { 2042 int index; 2043 final int count = mItemCount; 2044 if (firstPosition == 0) { 2045 index = 0; 2046 } else if (firstPosition + childCount == count) { 2047 index = count; 2048 } else { 2049 index = firstPosition + childCount / 2; 2050 } 2051 return (int) (firstPosition + childCount * (index / (float) count)); 2052 } 2053 } 2054 return 0; 2055 } 2056 2057 @Override 2058 protected int computeVerticalScrollRange() { 2059 int result; 2060 if (mSmoothScrollbarEnabled) { 2061 result = Math.max(mItemCount * 100, 0); 2062 if (mScrollY != 0) { 2063 // Compensate for overscroll 2064 result += Math.abs((int) ((float) mScrollY / getHeight() * mItemCount * 100)); 2065 } 2066 } else { 2067 result = mItemCount; 2068 } 2069 return result; 2070 } 2071 2072 @Override 2073 protected float getTopFadingEdgeStrength() { 2074 final int count = getChildCount(); 2075 final float fadeEdge = super.getTopFadingEdgeStrength(); 2076 if (count == 0) { 2077 return fadeEdge; 2078 } else { 2079 if (mFirstPosition > 0) { 2080 return 1.0f; 2081 } 2082 2083 final int top = getChildAt(0).getTop(); 2084 final float fadeLength = getVerticalFadingEdgeLength(); 2085 return top < mPaddingTop ? -(top - mPaddingTop) / fadeLength : fadeEdge; 2086 } 2087 } 2088 2089 @Override 2090 protected float getBottomFadingEdgeStrength() { 2091 final int count = getChildCount(); 2092 final float fadeEdge = super.getBottomFadingEdgeStrength(); 2093 if (count == 0) { 2094 return fadeEdge; 2095 } else { 2096 if (mFirstPosition + count - 1 < mItemCount - 1) { 2097 return 1.0f; 2098 } 2099 2100 final int bottom = getChildAt(count - 1).getBottom(); 2101 final int height = getHeight(); 2102 final float fadeLength = getVerticalFadingEdgeLength(); 2103 return bottom > height - mPaddingBottom ? 2104 (bottom - height + mPaddingBottom) / fadeLength : fadeEdge; 2105 } 2106 } 2107 2108 @Override 2109 protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { 2110 if (mSelector == null) { 2111 useDefaultSelector(); 2112 } 2113 final Rect listPadding = mListPadding; 2114 listPadding.left = mSelectionLeftPadding + mPaddingLeft; 2115 listPadding.top = mSelectionTopPadding + mPaddingTop; 2116 listPadding.right = mSelectionRightPadding + mPaddingRight; 2117 listPadding.bottom = mSelectionBottomPadding + mPaddingBottom; 2118 2119 // Check if our previous measured size was at a point where we should scroll later. 2120 if (mTranscriptMode == TRANSCRIPT_MODE_NORMAL) { 2121 final int childCount = getChildCount(); 2122 final int listBottom = getHeight() - getPaddingBottom(); 2123 final View lastChild = getChildAt(childCount - 1); 2124 final int lastBottom = lastChild != null ? lastChild.getBottom() : listBottom; 2125 mForceTranscriptScroll = mFirstPosition + childCount >= mLastHandledItemCount && 2126 lastBottom <= listBottom; 2127 } 2128 } 2129 2130 /** 2131 * Subclasses should NOT override this method but 2132 * {@link #layoutChildren()} instead. 2133 */ 2134 @Override 2135 protected void onLayout(boolean changed, int l, int t, int r, int b) { 2136 super.onLayout(changed, l, t, r, b); 2137 2138 mInLayout = true; 2139 2140 final int childCount = getChildCount(); 2141 if (changed) { 2142 for (int i = 0; i < childCount; i++) { 2143 getChildAt(i).forceLayout(); 2144 } 2145 mRecycler.markChildrenDirty(); 2146 } 2147 2148 layoutChildren(); 2149 mInLayout = false; 2150 2151 mOverscrollMax = (b - t) / OVERSCROLL_LIMIT_DIVISOR; 2152 2153 // TODO: Move somewhere sane. This doesn't belong in onLayout(). 2154 if (mFastScroll != null) { 2155 mFastScroll.onItemCountChanged(getChildCount(), mItemCount); 2156 } 2157 } 2158 2159 /** 2160 * @hide 2161 */ 2162 @Override 2163 protected boolean setFrame(int left, int top, int right, int bottom) { 2164 final boolean changed = super.setFrame(left, top, right, bottom); 2165 2166 if (changed) { 2167 // Reposition the popup when the frame has changed. This includes 2168 // translating the widget, not just changing its dimension. The 2169 // filter popup needs to follow the widget. 2170 final boolean visible = getWindowVisibility() == View.VISIBLE; 2171 if (mFiltered && visible && mPopup != null && mPopup.isShowing()) { 2172 positionPopup(); 2173 } 2174 } 2175 2176 return changed; 2177 } 2178 2179 /** 2180 * Subclasses must override this method to layout their children. 2181 */ 2182 protected void layoutChildren() { 2183 } 2184 2185 /** 2186 * @param focusedView view that holds accessibility focus 2187 * @return direct child that contains accessibility focus, or null if no 2188 * child contains accessibility focus 2189 */ 2190 View getAccessibilityFocusedChild(View focusedView) { 2191 ViewParent viewParent = focusedView.getParent(); 2192 while ((viewParent instanceof View) && (viewParent != this)) { 2193 focusedView = (View) viewParent; 2194 viewParent = viewParent.getParent(); 2195 } 2196 2197 if (!(viewParent instanceof View)) { 2198 return null; 2199 } 2200 2201 return focusedView; 2202 } 2203 2204 void updateScrollIndicators() { 2205 if (mScrollUp != null) { 2206 mScrollUp.setVisibility(canScrollUp() ? View.VISIBLE : View.INVISIBLE); 2207 } 2208 2209 if (mScrollDown != null) { 2210 mScrollDown.setVisibility(canScrollDown() ? View.VISIBLE : View.INVISIBLE); 2211 } 2212 } 2213 2214 private boolean canScrollUp() { 2215 boolean canScrollUp; 2216 // 0th element is not visible 2217 canScrollUp = mFirstPosition > 0; 2218 2219 // ... Or top of 0th element is not visible 2220 if (!canScrollUp) { 2221 if (getChildCount() > 0) { 2222 View child = getChildAt(0); 2223 canScrollUp = child.getTop() < mListPadding.top; 2224 } 2225 } 2226 2227 return canScrollUp; 2228 } 2229 2230 private boolean canScrollDown() { 2231 boolean canScrollDown; 2232 int count = getChildCount(); 2233 2234 // Last item is not visible 2235 canScrollDown = (mFirstPosition + count) < mItemCount; 2236 2237 // ... Or bottom of the last element is not visible 2238 if (!canScrollDown && count > 0) { 2239 View child = getChildAt(count - 1); 2240 canScrollDown = child.getBottom() > mBottom - mListPadding.bottom; 2241 } 2242 2243 return canScrollDown; 2244 } 2245 2246 @Override 2247 @ViewDebug.ExportedProperty 2248 public View getSelectedView() { 2249 if (mItemCount > 0 && mSelectedPosition >= 0) { 2250 return getChildAt(mSelectedPosition - mFirstPosition); 2251 } else { 2252 return null; 2253 } 2254 } 2255 2256 /** 2257 * List padding is the maximum of the normal view's padding and the padding of the selector. 2258 * 2259 * @see android.view.View#getPaddingTop() 2260 * @see #getSelector() 2261 * 2262 * @return The top list padding. 2263 */ 2264 public int getListPaddingTop() { 2265 return mListPadding.top; 2266 } 2267 2268 /** 2269 * List padding is the maximum of the normal view's padding and the padding of the selector. 2270 * 2271 * @see android.view.View#getPaddingBottom() 2272 * @see #getSelector() 2273 * 2274 * @return The bottom list padding. 2275 */ 2276 public int getListPaddingBottom() { 2277 return mListPadding.bottom; 2278 } 2279 2280 /** 2281 * List padding is the maximum of the normal view's padding and the padding of the selector. 2282 * 2283 * @see android.view.View#getPaddingLeft() 2284 * @see #getSelector() 2285 * 2286 * @return The left list padding. 2287 */ 2288 public int getListPaddingLeft() { 2289 return mListPadding.left; 2290 } 2291 2292 /** 2293 * List padding is the maximum of the normal view's padding and the padding of the selector. 2294 * 2295 * @see android.view.View#getPaddingRight() 2296 * @see #getSelector() 2297 * 2298 * @return The right list padding. 2299 */ 2300 public int getListPaddingRight() { 2301 return mListPadding.right; 2302 } 2303 2304 /** 2305 * Get a view and have it show the data associated with the specified 2306 * position. This is called when we have already discovered that the view is 2307 * not available for reuse in the recycle bin. The only choices left are 2308 * converting an old view or making a new one. 2309 * 2310 * @param position The position to display 2311 * @param isScrap Array of at least 1 boolean, the first entry will become true if 2312 * the returned view was taken from the scrap heap, false if otherwise. 2313 * 2314 * @return A view displaying the data associated with the specified position 2315 */ 2316 View obtainView(int position, boolean[] isScrap) { 2317 Trace.traceBegin(Trace.TRACE_TAG_VIEW, "obtainView"); 2318 2319 isScrap[0] = false; 2320 2321 // Check whether we have a transient state view. Attempt to re-bind the 2322 // data and discard the view if we fail. 2323 final View transientView = mRecycler.getTransientStateView(position); 2324 if (transientView != null) { 2325 final LayoutParams params = (LayoutParams) transientView.getLayoutParams(); 2326 2327 // If the view type hasn't changed, attempt to re-bind the data. 2328 if (params.viewType == mAdapter.getItemViewType(position)) { 2329 final View updatedView = mAdapter.getView(position, transientView, this); 2330 2331 // If we failed to re-bind the data, scrap the obtained view. 2332 if (updatedView != transientView) { 2333 setItemViewLayoutParams(updatedView, position); 2334 mRecycler.addScrapView(updatedView, position); 2335 } 2336 } 2337 2338 // Scrap view implies temporary detachment. 2339 isScrap[0] = true; 2340 return transientView; 2341 } 2342 2343 final View scrapView = mRecycler.getScrapView(position); 2344 final View child = mAdapter.getView(position, scrapView, this); 2345 if (scrapView != null) { 2346 if (child != scrapView) { 2347 // Failed to re-bind the data, return scrap to the heap. 2348 mRecycler.addScrapView(scrapView, position); 2349 } else { 2350 isScrap[0] = true; 2351 2352 child.dispatchFinishTemporaryDetach(); 2353 } 2354 } 2355 2356 if (mCacheColorHint != 0) { 2357 child.setDrawingCacheBackgroundColor(mCacheColorHint); 2358 } 2359 2360 if (child.getImportantForAccessibility() == IMPORTANT_FOR_ACCESSIBILITY_AUTO) { 2361 child.setImportantForAccessibility(IMPORTANT_FOR_ACCESSIBILITY_YES); 2362 } 2363 2364 setItemViewLayoutParams(child, position); 2365 2366 if (AccessibilityManager.getInstance(mContext).isEnabled()) { 2367 if (mAccessibilityDelegate == null) { 2368 mAccessibilityDelegate = new ListItemAccessibilityDelegate(); 2369 } 2370 if (child.getAccessibilityDelegate() == null) { 2371 child.setAccessibilityDelegate(mAccessibilityDelegate); 2372 } 2373 } 2374 2375 Trace.traceEnd(Trace.TRACE_TAG_VIEW); 2376 2377 return child; 2378 } 2379 2380 private void setItemViewLayoutParams(View child, int position) { 2381 final ViewGroup.LayoutParams vlp = child.getLayoutParams(); 2382 LayoutParams lp; 2383 if (vlp == null) { 2384 lp = (LayoutParams) generateDefaultLayoutParams(); 2385 } else if (!checkLayoutParams(vlp)) { 2386 lp = (LayoutParams) generateLayoutParams(vlp); 2387 } else { 2388 lp = (LayoutParams) vlp; 2389 } 2390 2391 if (mAdapterHasStableIds) { 2392 lp.itemId = mAdapter.getItemId(position); 2393 } 2394 lp.viewType = mAdapter.getItemViewType(position); 2395 child.setLayoutParams(lp); 2396 } 2397 2398 class ListItemAccessibilityDelegate extends AccessibilityDelegate { 2399 @Override 2400 public AccessibilityNodeInfo createAccessibilityNodeInfo(View host) { 2401 // If the data changed the children are invalid since the data model changed. 2402 // Hence, we pretend they do not exist. After a layout the children will sync 2403 // with the model at which point we notify that the accessibility state changed, 2404 // so a service will be able to re-fetch the views. 2405 if (mDataChanged) { 2406 return null; 2407 } 2408 return super.createAccessibilityNodeInfo(host); 2409 } 2410 2411 @Override 2412 public void onInitializeAccessibilityNodeInfo(View host, AccessibilityNodeInfo info) { 2413 super.onInitializeAccessibilityNodeInfo(host, info); 2414 2415 final int position = getPositionForView(host); 2416 onInitializeAccessibilityNodeInfoForItem(host, position, info); 2417 } 2418 2419 @Override 2420 public boolean performAccessibilityAction(View host, int action, Bundle arguments) { 2421 if (super.performAccessibilityAction(host, action, arguments)) { 2422 return true; 2423 } 2424 2425 final int position = getPositionForView(host); 2426 final ListAdapter adapter = getAdapter(); 2427 2428 if ((position == INVALID_POSITION) || (adapter == null)) { 2429 // Cannot perform actions on invalid items. 2430 return false; 2431 } 2432 2433 if (!isEnabled() || !adapter.isEnabled(position)) { 2434 // Cannot perform actions on disabled items. 2435 return false; 2436 } 2437 2438 final long id = getItemIdAtPosition(position); 2439 2440 switch (action) { 2441 case AccessibilityNodeInfo.ACTION_CLEAR_SELECTION: { 2442 if (getSelectedItemPosition() == position) { 2443 setSelection(INVALID_POSITION); 2444 return true; 2445 } 2446 } return false; 2447 case AccessibilityNodeInfo.ACTION_SELECT: { 2448 if (getSelectedItemPosition() != position) { 2449 setSelection(position); 2450 return true; 2451 } 2452 } return false; 2453 case AccessibilityNodeInfo.ACTION_CLICK: { 2454 if (isClickable()) { 2455 return performItemClick(host, position, id); 2456 } 2457 } return false; 2458 case AccessibilityNodeInfo.ACTION_LONG_CLICK: { 2459 if (isLongClickable()) { 2460 return performLongPress(host, position, id); 2461 } 2462 } return false; 2463 } 2464 2465 return false; 2466 } 2467 } 2468 2469 /** 2470 * Initializes an {@link AccessibilityNodeInfo} with information about a 2471 * particular item in the list. 2472 * 2473 * @param view View representing the list item. 2474 * @param position Position of the list item within the adapter. 2475 * @param info Node info to populate. 2476 */ 2477 public void onInitializeAccessibilityNodeInfoForItem( 2478 View view, int position, AccessibilityNodeInfo info) { 2479 final ListAdapter adapter = getAdapter(); 2480 if (position == INVALID_POSITION || adapter == null) { 2481 // The item doesn't exist, so there's not much we can do here. 2482 return; 2483 } 2484 2485 if (!isEnabled() || !adapter.isEnabled(position)) { 2486 info.setEnabled(false); 2487 return; 2488 } 2489 2490 if (position == getSelectedItemPosition()) { 2491 info.setSelected(true); 2492 info.addAction(AccessibilityNodeInfo.ACTION_CLEAR_SELECTION); 2493 } else { 2494 info.addAction(AccessibilityNodeInfo.ACTION_SELECT); 2495 } 2496 2497 if (isClickable()) { 2498 info.addAction(AccessibilityNodeInfo.ACTION_CLICK); 2499 info.setClickable(true); 2500 } 2501 2502 if (isLongClickable()) { 2503 info.addAction(AccessibilityNodeInfo.ACTION_LONG_CLICK); 2504 info.setLongClickable(true); 2505 } 2506 } 2507 2508 /** 2509 * Positions the selector in a way that mimics touch. 2510 */ 2511 void positionSelectorLikeTouch(int position, View sel, float x, float y) { 2512 positionSelectorLikeFocus(position, sel); 2513 2514 if (mSelector != null && position != INVALID_POSITION) { 2515 mSelector.setHotspot(x, y); 2516 } 2517 } 2518 2519 /** 2520 * Positions the selector in a way that mimics keyboard focus. 2521 */ 2522 void positionSelectorLikeFocus(int position, View sel) { 2523 // If we're changing position, update the visibility since the selector 2524 // is technically being detached from the previous selection. 2525 final Drawable selector = mSelector; 2526 final boolean manageState = selector != null && mSelectorPosition != position 2527 && position != INVALID_POSITION; 2528 if (manageState) { 2529 selector.setVisible(false, false); 2530 } 2531 2532 positionSelector(position, sel); 2533 2534 if (manageState) { 2535 final Rect bounds = mSelectorRect; 2536 final float x = bounds.exactCenterX(); 2537 final float y = bounds.exactCenterY(); 2538 selector.setVisible(getVisibility() == VISIBLE, false); 2539 selector.setHotspot(x, y); 2540 } 2541 } 2542 2543 void positionSelector(int position, View sel) { 2544 if (position != INVALID_POSITION) { 2545 mSelectorPosition = position; 2546 } 2547 2548 final Rect selectorRect = mSelectorRect; 2549 selectorRect.set(sel.getLeft(), sel.getTop(), sel.getRight(), sel.getBottom()); 2550 if (sel instanceof SelectionBoundsAdjuster) { 2551 ((SelectionBoundsAdjuster)sel).adjustListItemSelectionBounds(selectorRect); 2552 } 2553 2554 // Adjust for selection padding. 2555 selectorRect.left -= mSelectionLeftPadding; 2556 selectorRect.top -= mSelectionTopPadding; 2557 selectorRect.right += mSelectionRightPadding; 2558 selectorRect.bottom += mSelectionBottomPadding; 2559 2560 // Update the selector drawable. 2561 final Drawable selector = mSelector; 2562 if (selector != null) { 2563 selector.setBounds(selectorRect); 2564 } 2565 2566 final boolean isChildViewEnabled = mIsChildViewEnabled; 2567 if (sel.isEnabled() != isChildViewEnabled) { 2568 mIsChildViewEnabled = !isChildViewEnabled; 2569 if (getSelectedItemPosition() != INVALID_POSITION) { 2570 refreshDrawableState(); 2571 } 2572 } 2573 } 2574 2575 @Override 2576 protected void dispatchDraw(Canvas canvas) { 2577 int saveCount = 0; 2578 final boolean clipToPadding = (mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK; 2579 if (clipToPadding) { 2580 saveCount = canvas.save(); 2581 final int scrollX = mScrollX; 2582 final int scrollY = mScrollY; 2583 canvas.clipRect(scrollX + mPaddingLeft, scrollY + mPaddingTop, 2584 scrollX + mRight - mLeft - mPaddingRight, 2585 scrollY + mBottom - mTop - mPaddingBottom); 2586 mGroupFlags &= ~CLIP_TO_PADDING_MASK; 2587 } 2588 2589 final boolean drawSelectorOnTop = mDrawSelectorOnTop; 2590 if (!drawSelectorOnTop) { 2591 drawSelector(canvas); 2592 } 2593 2594 super.dispatchDraw(canvas); 2595 2596 if (drawSelectorOnTop) { 2597 drawSelector(canvas); 2598 } 2599 2600 if (clipToPadding) { 2601 canvas.restoreToCount(saveCount); 2602 mGroupFlags |= CLIP_TO_PADDING_MASK; 2603 } 2604 } 2605 2606 @Override 2607 protected boolean isPaddingOffsetRequired() { 2608 return (mGroupFlags & CLIP_TO_PADDING_MASK) != CLIP_TO_PADDING_MASK; 2609 } 2610 2611 @Override 2612 protected int getLeftPaddingOffset() { 2613 return (mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK ? 0 : -mPaddingLeft; 2614 } 2615 2616 @Override 2617 protected int getTopPaddingOffset() { 2618 return (mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK ? 0 : -mPaddingTop; 2619 } 2620 2621 @Override 2622 protected int getRightPaddingOffset() { 2623 return (mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK ? 0 : mPaddingRight; 2624 } 2625 2626 @Override 2627 protected int getBottomPaddingOffset() { 2628 return (mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK ? 0 : mPaddingBottom; 2629 } 2630 2631 @Override 2632 protected void onSizeChanged(int w, int h, int oldw, int oldh) { 2633 if (getChildCount() > 0) { 2634 mDataChanged = true; 2635 rememberSyncState(); 2636 } 2637 2638 if (mFastScroll != null) { 2639 mFastScroll.onSizeChanged(w, h, oldw, oldh); 2640 } 2641 } 2642 2643 /** 2644 * @return True if the current touch mode requires that we draw the selector in the pressed 2645 * state. 2646 */ 2647 boolean touchModeDrawsInPressedState() { 2648 // FIXME use isPressed for this 2649 switch (mTouchMode) { 2650 case TOUCH_MODE_TAP: 2651 case TOUCH_MODE_DONE_WAITING: 2652 return true; 2653 default: 2654 return false; 2655 } 2656 } 2657 2658 /** 2659 * Indicates whether this view is in a state where the selector should be drawn. This will 2660 * happen if we have focus but are not in touch mode, or we are in the middle of displaying 2661 * the pressed state for an item. 2662 * 2663 * @return True if the selector should be shown 2664 */ 2665 boolean shouldShowSelector() { 2666 return (isFocused() && !isInTouchMode()) || (touchModeDrawsInPressedState() && isPressed()); 2667 } 2668 2669 private void drawSelector(Canvas canvas) { 2670 if (!mSelectorRect.isEmpty()) { 2671 final Drawable selector = mSelector; 2672 selector.setBounds(mSelectorRect); 2673 selector.draw(canvas); 2674 } 2675 } 2676 2677 /** 2678 * Controls whether the selection highlight drawable should be drawn on top of the item or 2679 * behind it. 2680 * 2681 * @param onTop If true, the selector will be drawn on the item it is highlighting. The default 2682 * is false. 2683 * 2684 * @attr ref android.R.styleable#AbsListView_drawSelectorOnTop 2685 */ 2686 public void setDrawSelectorOnTop(boolean onTop) { 2687 mDrawSelectorOnTop = onTop; 2688 } 2689 2690 /** 2691 * Set a Drawable that should be used to highlight the currently selected item. 2692 * 2693 * @param resID A Drawable resource to use as the selection highlight. 2694 * 2695 * @attr ref android.R.styleable#AbsListView_listSelector 2696 */ 2697 public void setSelector(int resID) { 2698 setSelector(getContext().getDrawable(resID)); 2699 } 2700 2701 public void setSelector(Drawable sel) { 2702 if (mSelector != null) { 2703 mSelector.setCallback(null); 2704 unscheduleDrawable(mSelector); 2705 } 2706 mSelector = sel; 2707 Rect padding = new Rect(); 2708 sel.getPadding(padding); 2709 mSelectionLeftPadding = padding.left; 2710 mSelectionTopPadding = padding.top; 2711 mSelectionRightPadding = padding.right; 2712 mSelectionBottomPadding = padding.bottom; 2713 sel.setCallback(this); 2714 updateSelectorState(); 2715 } 2716 2717 /** 2718 * Returns the selector {@link android.graphics.drawable.Drawable} that is used to draw the 2719 * selection in the list. 2720 * 2721 * @return the drawable used to display the selector 2722 */ 2723 public Drawable getSelector() { 2724 return mSelector; 2725 } 2726 2727 /** 2728 * Sets the selector state to "pressed" and posts a CheckForKeyLongPress to see if 2729 * this is a long press. 2730 */ 2731 void keyPressed() { 2732 if (!isEnabled() || !isClickable()) { 2733 return; 2734 } 2735 2736 Drawable selector = mSelector; 2737 Rect selectorRect = mSelectorRect; 2738 if (selector != null && (isFocused() || touchModeDrawsInPressedState()) 2739 && !selectorRect.isEmpty()) { 2740 2741 final View v = getChildAt(mSelectedPosition - mFirstPosition); 2742 2743 if (v != null) { 2744 if (v.hasFocusable()) return; 2745 v.setPressed(true); 2746 } 2747 setPressed(true); 2748 2749 final boolean longClickable = isLongClickable(); 2750 Drawable d = selector.getCurrent(); 2751 if (d != null && d instanceof TransitionDrawable) { 2752 if (longClickable) { 2753 ((TransitionDrawable) d).startTransition( 2754 ViewConfiguration.getLongPressTimeout()); 2755 } else { 2756 ((TransitionDrawable) d).resetTransition(); 2757 } 2758 } 2759 if (longClickable && !mDataChanged) { 2760 if (mPendingCheckForKeyLongPress == null) { 2761 mPendingCheckForKeyLongPress = new CheckForKeyLongPress(); 2762 } 2763 mPendingCheckForKeyLongPress.rememberWindowAttachCount(); 2764 postDelayed(mPendingCheckForKeyLongPress, ViewConfiguration.getLongPressTimeout()); 2765 } 2766 } 2767 } 2768 2769 public void setScrollIndicators(View up, View down) { 2770 mScrollUp = up; 2771 mScrollDown = down; 2772 } 2773 2774 void updateSelectorState() { 2775 if (mSelector != null) { 2776 if (shouldShowSelector()) { 2777 mSelector.setState(getDrawableState()); 2778 } else { 2779 mSelector.setState(StateSet.NOTHING); 2780 } 2781 } 2782 } 2783 2784 @Override 2785 protected void drawableStateChanged() { 2786 super.drawableStateChanged(); 2787 updateSelectorState(); 2788 } 2789 2790 @Override 2791 protected int[] onCreateDrawableState(int extraSpace) { 2792 // If the child view is enabled then do the default behavior. 2793 if (mIsChildViewEnabled) { 2794 // Common case 2795 return super.onCreateDrawableState(extraSpace); 2796 } 2797 2798 // The selector uses this View's drawable state. The selected child view 2799 // is disabled, so we need to remove the enabled state from the drawable 2800 // states. 2801 final int enabledState = ENABLED_STATE_SET[0]; 2802 2803 // If we don't have any extra space, it will return one of the static state arrays, 2804 // and clearing the enabled state on those arrays is a bad thing! If we specify 2805 // we need extra space, it will create+copy into a new array that safely mutable. 2806 int[] state = super.onCreateDrawableState(extraSpace + 1); 2807 int enabledPos = -1; 2808 for (int i = state.length - 1; i >= 0; i--) { 2809 if (state[i] == enabledState) { 2810 enabledPos = i; 2811 break; 2812 } 2813 } 2814 2815 // Remove the enabled state 2816 if (enabledPos >= 0) { 2817 System.arraycopy(state, enabledPos + 1, state, enabledPos, 2818 state.length - enabledPos - 1); 2819 } 2820 2821 return state; 2822 } 2823 2824 @Override 2825 public boolean verifyDrawable(Drawable dr) { 2826 return mSelector == dr || super.verifyDrawable(dr); 2827 } 2828 2829 @Override 2830 public void jumpDrawablesToCurrentState() { 2831 super.jumpDrawablesToCurrentState(); 2832 if (mSelector != null) mSelector.jumpToCurrentState(); 2833 } 2834 2835 @Override 2836 protected void onAttachedToWindow() { 2837 super.onAttachedToWindow(); 2838 2839 final ViewTreeObserver treeObserver = getViewTreeObserver(); 2840 treeObserver.addOnTouchModeChangeListener(this); 2841 if (mTextFilterEnabled && mPopup != null && !mGlobalLayoutListenerAddedFilter) { 2842 treeObserver.addOnGlobalLayoutListener(this); 2843 } 2844 2845 if (mAdapter != null && mDataSetObserver == null) { 2846 mDataSetObserver = new AdapterDataSetObserver(); 2847 mAdapter.registerDataSetObserver(mDataSetObserver); 2848 2849 // Data may have changed while we were detached. Refresh. 2850 mDataChanged = true; 2851 mOldItemCount = mItemCount; 2852 mItemCount = mAdapter.getCount(); 2853 } 2854 } 2855 2856 @Override 2857 protected void onDetachedFromWindow() { 2858 super.onDetachedFromWindow(); 2859 2860 mIsDetaching = true; 2861 2862 // Dismiss the popup in case onSaveInstanceState() was not invoked 2863 dismissPopup(); 2864 2865 // Detach any view left in the scrap heap 2866 mRecycler.clear(); 2867 2868 final ViewTreeObserver treeObserver = getViewTreeObserver(); 2869 treeObserver.removeOnTouchModeChangeListener(this); 2870 if (mTextFilterEnabled && mPopup != null) { 2871 treeObserver.removeOnGlobalLayoutListener(this); 2872 mGlobalLayoutListenerAddedFilter = false; 2873 } 2874 2875 if (mAdapter != null && mDataSetObserver != null) { 2876 mAdapter.unregisterDataSetObserver(mDataSetObserver); 2877 mDataSetObserver = null; 2878 } 2879 2880 if (mScrollStrictSpan != null) { 2881 mScrollStrictSpan.finish(); 2882 mScrollStrictSpan = null; 2883 } 2884 2885 if (mFlingStrictSpan != null) { 2886 mFlingStrictSpan.finish(); 2887 mFlingStrictSpan = null; 2888 } 2889 2890 if (mFlingRunnable != null) { 2891 removeCallbacks(mFlingRunnable); 2892 } 2893 2894 if (mPositionScroller != null) { 2895 mPositionScroller.stop(); 2896 } 2897 2898 if (mClearScrollingCache != null) { 2899 removeCallbacks(mClearScrollingCache); 2900 } 2901 2902 if (mPerformClick != null) { 2903 removeCallbacks(mPerformClick); 2904 } 2905 2906 if (mTouchModeReset != null) { 2907 removeCallbacks(mTouchModeReset); 2908 mTouchModeReset.run(); 2909 } 2910 2911 mIsDetaching = false; 2912 } 2913 2914 @Override 2915 public void onWindowFocusChanged(boolean hasWindowFocus) { 2916 super.onWindowFocusChanged(hasWindowFocus); 2917 2918 final int touchMode = isInTouchMode() ? TOUCH_MODE_ON : TOUCH_MODE_OFF; 2919 2920 if (!hasWindowFocus) { 2921 setChildrenDrawingCacheEnabled(false); 2922 if (mFlingRunnable != null) { 2923 removeCallbacks(mFlingRunnable); 2924 // let the fling runnable report it's new state which 2925 // should be idle 2926 mFlingRunnable.endFling(); 2927 if (mPositionScroller != null) { 2928 mPositionScroller.stop(); 2929 } 2930 if (mScrollY != 0) { 2931 mScrollY = 0; 2932 invalidateParentCaches(); 2933 finishGlows(); 2934 invalidate(); 2935 } 2936 } 2937 // Always hide the type filter 2938 dismissPopup(); 2939 2940 if (touchMode == TOUCH_MODE_OFF) { 2941 // Remember the last selected element 2942 mResurrectToPosition = mSelectedPosition; 2943 } 2944 } else { 2945 if (mFiltered && !mPopupHidden) { 2946 // Show the type filter only if a filter is in effect 2947 showPopup(); 2948 } 2949 2950 // If we changed touch mode since the last time we had focus 2951 if (touchMode != mLastTouchMode && mLastTouchMode != TOUCH_MODE_UNKNOWN) { 2952 // If we come back in trackball mode, we bring the selection back 2953 if (touchMode == TOUCH_MODE_OFF) { 2954 // This will trigger a layout 2955 resurrectSelection(); 2956 2957 // If we come back in touch mode, then we want to hide the selector 2958 } else { 2959 hideSelector(); 2960 mLayoutMode = LAYOUT_NORMAL; 2961 layoutChildren(); 2962 } 2963 } 2964 } 2965 2966 mLastTouchMode = touchMode; 2967 } 2968 2969 @Override 2970 public void onRtlPropertiesChanged(int layoutDirection) { 2971 super.onRtlPropertiesChanged(layoutDirection); 2972 if (mFastScroll != null) { 2973 mFastScroll.setScrollbarPosition(getVerticalScrollbarPosition()); 2974 } 2975 } 2976 2977 /** 2978 * Creates the ContextMenuInfo returned from {@link #getContextMenuInfo()}. This 2979 * methods knows the view, position and ID of the item that received the 2980 * long press. 2981 * 2982 * @param view The view that received the long press. 2983 * @param position The position of the item that received the long press. 2984 * @param id The ID of the item that received the long press. 2985 * @return The extra information that should be returned by 2986 * {@link #getContextMenuInfo()}. 2987 */ 2988 ContextMenuInfo createContextMenuInfo(View view, int position, long id) { 2989 return new AdapterContextMenuInfo(view, position, id); 2990 } 2991 2992 @Override 2993 public void onCancelPendingInputEvents() { 2994 super.onCancelPendingInputEvents(); 2995 if (mPerformClick != null) { 2996 removeCallbacks(mPerformClick); 2997 } 2998 if (mPendingCheckForTap != null) { 2999 removeCallbacks(mPendingCheckForTap); 3000 } 3001 if (mPendingCheckForLongPress != null) { 3002 removeCallbacks(mPendingCheckForLongPress); 3003 } 3004 if (mPendingCheckForKeyLongPress != null) { 3005 removeCallbacks(mPendingCheckForKeyLongPress); 3006 } 3007 } 3008 3009 /** 3010 * A base class for Runnables that will check that their view is still attached to 3011 * the original window as when the Runnable was created. 3012 * 3013 */ 3014 private class WindowRunnnable { 3015 private int mOriginalAttachCount; 3016 3017 public void rememberWindowAttachCount() { 3018 mOriginalAttachCount = getWindowAttachCount(); 3019 } 3020 3021 public boolean sameWindow() { 3022 return getWindowAttachCount() == mOriginalAttachCount; 3023 } 3024 } 3025 3026 private class PerformClick extends WindowRunnnable implements Runnable { 3027 int mClickMotionPosition; 3028 3029 @Override 3030 public void run() { 3031 // The data has changed since we posted this action in the event queue, 3032 // bail out before bad things happen 3033 if (mDataChanged) return; 3034 3035 final ListAdapter adapter = mAdapter; 3036 final int motionPosition = mClickMotionPosition; 3037 if (adapter != null && mItemCount > 0 && 3038 motionPosition != INVALID_POSITION && 3039 motionPosition < adapter.getCount() && sameWindow()) { 3040 final View view = getChildAt(motionPosition - mFirstPosition); 3041 // If there is no view, something bad happened (the view scrolled off the 3042 // screen, etc.) and we should cancel the click 3043 if (view != null) { 3044 performItemClick(view, motionPosition, adapter.getItemId(motionPosition)); 3045 } 3046 } 3047 } 3048 } 3049 3050 private class CheckForLongPress extends WindowRunnnable implements Runnable { 3051 @Override 3052 public void run() { 3053 final int motionPosition = mMotionPosition; 3054 final View child = getChildAt(motionPosition - mFirstPosition); 3055 if (child != null) { 3056 final int longPressPosition = mMotionPosition; 3057 final long longPressId = mAdapter.getItemId(mMotionPosition); 3058 3059 boolean handled = false; 3060 if (sameWindow() && !mDataChanged) { 3061 handled = performLongPress(child, longPressPosition, longPressId); 3062 } 3063 if (handled) { 3064 mTouchMode = TOUCH_MODE_REST; 3065 setPressed(false); 3066 child.setPressed(false); 3067 } else { 3068 mTouchMode = TOUCH_MODE_DONE_WAITING; 3069 } 3070 } 3071 } 3072 } 3073 3074 private class CheckForKeyLongPress extends WindowRunnnable implements Runnable { 3075 @Override 3076 public void run() { 3077 if (isPressed() && mSelectedPosition >= 0) { 3078 int index = mSelectedPosition - mFirstPosition; 3079 View v = getChildAt(index); 3080 3081 if (!mDataChanged) { 3082 boolean handled = false; 3083 if (sameWindow()) { 3084 handled = performLongPress(v, mSelectedPosition, mSelectedRowId); 3085 } 3086 if (handled) { 3087 setPressed(false); 3088 v.setPressed(false); 3089 } 3090 } else { 3091 setPressed(false); 3092 if (v != null) v.setPressed(false); 3093 } 3094 } 3095 } 3096 } 3097 3098 boolean performLongPress(final View child, 3099 final int longPressPosition, final long longPressId) { 3100 // CHOICE_MODE_MULTIPLE_MODAL takes over long press. 3101 if (mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL) { 3102 if (mChoiceActionMode == null && 3103 (mChoiceActionMode = startActionMode(mMultiChoiceModeCallback)) != null) { 3104 setItemChecked(longPressPosition, true); 3105 performHapticFeedback(HapticFeedbackConstants.LONG_PRESS); 3106 } 3107 return true; 3108 } 3109 3110 boolean handled = false; 3111 if (mOnItemLongClickListener != null) { 3112 handled = mOnItemLongClickListener.onItemLongClick(AbsListView.this, child, 3113 longPressPosition, longPressId); 3114 } 3115 if (!handled) { 3116 mContextMenuInfo = createContextMenuInfo(child, longPressPosition, longPressId); 3117 handled = super.showContextMenuForChild(AbsListView.this); 3118 } 3119 if (handled) { 3120 performHapticFeedback(HapticFeedbackConstants.LONG_PRESS); 3121 } 3122 return handled; 3123 } 3124 3125 @Override 3126 protected ContextMenuInfo getContextMenuInfo() { 3127 return mContextMenuInfo; 3128 } 3129 3130 /** @hide */ 3131 @Override 3132 public boolean showContextMenu(float x, float y, int metaState) { 3133 final int position = pointToPosition((int)x, (int)y); 3134 if (position != INVALID_POSITION) { 3135 final long id = mAdapter.getItemId(position); 3136 View child = getChildAt(position - mFirstPosition); 3137 if (child != null) { 3138 mContextMenuInfo = createContextMenuInfo(child, position, id); 3139 return super.showContextMenuForChild(AbsListView.this); 3140 } 3141 } 3142 return super.showContextMenu(x, y, metaState); 3143 } 3144 3145 @Override 3146 public boolean showContextMenuForChild(View originalView) { 3147 final int longPressPosition = getPositionForView(originalView); 3148 if (longPressPosition >= 0) { 3149 final long longPressId = mAdapter.getItemId(longPressPosition); 3150 boolean handled = false; 3151 3152 if (mOnItemLongClickListener != null) { 3153 handled = mOnItemLongClickListener.onItemLongClick(AbsListView.this, originalView, 3154 longPressPosition, longPressId); 3155 } 3156 if (!handled) { 3157 mContextMenuInfo = createContextMenuInfo( 3158 getChildAt(longPressPosition - mFirstPosition), 3159 longPressPosition, longPressId); 3160 handled = super.showContextMenuForChild(originalView); 3161 } 3162 3163 return handled; 3164 } 3165 return false; 3166 } 3167 3168 @Override 3169 public boolean onKeyDown(int keyCode, KeyEvent event) { 3170 return false; 3171 } 3172 3173 @Override 3174 public boolean onKeyUp(int keyCode, KeyEvent event) { 3175 if (KeyEvent.isConfirmKey(keyCode)) { 3176 if (!isEnabled()) { 3177 return true; 3178 } 3179 if (isClickable() && isPressed() && 3180 mSelectedPosition >= 0 && mAdapter != null && 3181 mSelectedPosition < mAdapter.getCount()) { 3182 3183 final View view = getChildAt(mSelectedPosition - mFirstPosition); 3184 if (view != null) { 3185 performItemClick(view, mSelectedPosition, mSelectedRowId); 3186 view.setPressed(false); 3187 } 3188 setPressed(false); 3189 return true; 3190 } 3191 } 3192 return super.onKeyUp(keyCode, event); 3193 } 3194 3195 @Override 3196 protected void dispatchSetPressed(boolean pressed) { 3197 // Don't dispatch setPressed to our children. We call setPressed on ourselves to 3198 // get the selector in the right state, but we don't want to press each child. 3199 } 3200 3201 /** 3202 * Maps a point to a position in the list. 3203 * 3204 * @param x X in local coordinate 3205 * @param y Y in local coordinate 3206 * @return The position of the item which contains the specified point, or 3207 * {@link #INVALID_POSITION} if the point does not intersect an item. 3208 */ 3209 public int pointToPosition(int x, int y) { 3210 Rect frame = mTouchFrame; 3211 if (frame == null) { 3212 mTouchFrame = new Rect(); 3213 frame = mTouchFrame; 3214 } 3215 3216 final int count = getChildCount(); 3217 for (int i = count - 1; i >= 0; i--) { 3218 final View child = getChildAt(i); 3219 if (child.getVisibility() == View.VISIBLE) { 3220 child.getHitRect(frame); 3221 if (frame.contains(x, y)) { 3222 return mFirstPosition + i; 3223 } 3224 } 3225 } 3226 return INVALID_POSITION; 3227 } 3228 3229 3230 /** 3231 * Maps a point to a the rowId of the item which intersects that point. 3232 * 3233 * @param x X in local coordinate 3234 * @param y Y in local coordinate 3235 * @return The rowId of the item which contains the specified point, or {@link #INVALID_ROW_ID} 3236 * if the point does not intersect an item. 3237 */ 3238 public long pointToRowId(int x, int y) { 3239 int position = pointToPosition(x, y); 3240 if (position >= 0) { 3241 return mAdapter.getItemId(position); 3242 } 3243 return INVALID_ROW_ID; 3244 } 3245 3246 private final class CheckForTap implements Runnable { 3247 float x; 3248 float y; 3249 3250 @Override 3251 public void run() { 3252 if (mTouchMode == TOUCH_MODE_DOWN) { 3253 mTouchMode = TOUCH_MODE_TAP; 3254 final View child = getChildAt(mMotionPosition - mFirstPosition); 3255 if (child != null && !child.hasFocusable()) { 3256 mLayoutMode = LAYOUT_NORMAL; 3257 3258 if (!mDataChanged) { 3259 child.setPressed(true); 3260 setPressed(true); 3261 layoutChildren(); 3262 positionSelector(mMotionPosition, child); 3263 refreshDrawableState(); 3264 3265 final int longPressTimeout = ViewConfiguration.getLongPressTimeout(); 3266 final boolean longClickable = isLongClickable(); 3267 3268 if (mSelector != null) { 3269 final Drawable d = mSelector.getCurrent(); 3270 if (d != null && d instanceof TransitionDrawable) { 3271 if (longClickable) { 3272 ((TransitionDrawable) d).startTransition(longPressTimeout); 3273 } else { 3274 ((TransitionDrawable) d).resetTransition(); 3275 } 3276 } 3277 mSelector.setHotspot(x, y); 3278 } 3279 3280 if (longClickable) { 3281 if (mPendingCheckForLongPress == null) { 3282 mPendingCheckForLongPress = new CheckForLongPress(); 3283 } 3284 mPendingCheckForLongPress.rememberWindowAttachCount(); 3285 postDelayed(mPendingCheckForLongPress, longPressTimeout); 3286 } else { 3287 mTouchMode = TOUCH_MODE_DONE_WAITING; 3288 } 3289 } else { 3290 mTouchMode = TOUCH_MODE_DONE_WAITING; 3291 } 3292 } 3293 } 3294 } 3295 } 3296 3297 private boolean startScrollIfNeeded(int x, int y, MotionEvent vtev) { 3298 // Check if we have moved far enough that it looks more like a 3299 // scroll than a tap 3300 final int deltaY = y - mMotionY; 3301 final int distance = Math.abs(deltaY); 3302 final boolean overscroll = mScrollY != 0; 3303 if ((overscroll || distance > mTouchSlop) && 3304 (getNestedScrollAxes() & SCROLL_AXIS_VERTICAL) == 0) { 3305 createScrollingCache(); 3306 if (overscroll) { 3307 mTouchMode = TOUCH_MODE_OVERSCROLL; 3308 mMotionCorrection = 0; 3309 } else { 3310 mTouchMode = TOUCH_MODE_SCROLL; 3311 mMotionCorrection = deltaY > 0 ? mTouchSlop : -mTouchSlop; 3312 } 3313 removeCallbacks(mPendingCheckForLongPress); 3314 setPressed(false); 3315 final View motionView = getChildAt(mMotionPosition - mFirstPosition); 3316 if (motionView != null) { 3317 motionView.setPressed(false); 3318 } 3319 reportScrollStateChange(OnScrollListener.SCROLL_STATE_TOUCH_SCROLL); 3320 // Time to start stealing events! Once we've stolen them, don't let anyone 3321 // steal from us 3322 final ViewParent parent = getParent(); 3323 if (parent != null) { 3324 parent.requestDisallowInterceptTouchEvent(true); 3325 } 3326 scrollIfNeeded(x, y, vtev); 3327 return true; 3328 } 3329 3330 return false; 3331 } 3332 3333 private void scrollIfNeeded(int x, int y, MotionEvent vtev) { 3334 int rawDeltaY = y - mMotionY; 3335 int scrollOffsetCorrection = 0; 3336 int scrollConsumedCorrection = 0; 3337 if (mLastY == Integer.MIN_VALUE) { 3338 rawDeltaY -= mMotionCorrection; 3339 } 3340 if (dispatchNestedPreScroll(0, mLastY != Integer.MIN_VALUE ? mLastY - y : -rawDeltaY, 3341 mScrollConsumed, mScrollOffset)) { 3342 rawDeltaY += mScrollConsumed[1]; 3343 scrollOffsetCorrection = -mScrollOffset[1]; 3344 scrollConsumedCorrection = mScrollConsumed[1]; 3345 if (vtev != null) { 3346 vtev.offsetLocation(0, mScrollOffset[1]); 3347 mNestedYOffset += mScrollOffset[1]; 3348 } 3349 } 3350 final int deltaY = rawDeltaY; 3351 int incrementalDeltaY = 3352 mLastY != Integer.MIN_VALUE ? y - mLastY + scrollConsumedCorrection : deltaY; 3353 int lastYCorrection = 0; 3354 3355 if (mTouchMode == TOUCH_MODE_SCROLL) { 3356 if (PROFILE_SCROLLING) { 3357 if (!mScrollProfilingStarted) { 3358 Debug.startMethodTracing("AbsListViewScroll"); 3359 mScrollProfilingStarted = true; 3360 } 3361 } 3362 3363 if (mScrollStrictSpan == null) { 3364 // If it's non-null, we're already in a scroll. 3365 mScrollStrictSpan = StrictMode.enterCriticalSpan("AbsListView-scroll"); 3366 } 3367 3368 if (y != mLastY) { 3369 // We may be here after stopping a fling and continuing to scroll. 3370 // If so, we haven't disallowed intercepting touch events yet. 3371 // Make sure that we do so in case we're in a parent that can intercept. 3372 if ((mGroupFlags & FLAG_DISALLOW_INTERCEPT) == 0 && 3373 Math.abs(rawDeltaY) > mTouchSlop) { 3374 final ViewParent parent = getParent(); 3375 if (parent != null) { 3376 parent.requestDisallowInterceptTouchEvent(true); 3377 } 3378 } 3379 3380 final int motionIndex; 3381 if (mMotionPosition >= 0) { 3382 motionIndex = mMotionPosition - mFirstPosition; 3383 } else { 3384 // If we don't have a motion position that we can reliably track, 3385 // pick something in the middle to make a best guess at things below. 3386 motionIndex = getChildCount() / 2; 3387 } 3388 3389 int motionViewPrevTop = 0; 3390 View motionView = this.getChildAt(motionIndex); 3391 if (motionView != null) { 3392 motionViewPrevTop = motionView.getTop(); 3393 } 3394 3395 // No need to do all this work if we're not going to move anyway 3396 boolean atEdge = false; 3397 if (incrementalDeltaY != 0) { 3398 atEdge = trackMotionScroll(deltaY, incrementalDeltaY); 3399 } 3400 3401 // Check to see if we have bumped into the scroll limit 3402 motionView = this.getChildAt(motionIndex); 3403 if (motionView != null) { 3404 // Check if the top of the motion view is where it is 3405 // supposed to be 3406 final int motionViewRealTop = motionView.getTop(); 3407 if (atEdge) { 3408 // Apply overscroll 3409 3410 int overscroll = -incrementalDeltaY - 3411 (motionViewRealTop - motionViewPrevTop); 3412 if (dispatchNestedScroll(0, overscroll - incrementalDeltaY, 0, overscroll, 3413 mScrollOffset)) { 3414 lastYCorrection -= mScrollOffset[1]; 3415 if (vtev != null) { 3416 vtev.offsetLocation(0, mScrollOffset[1]); 3417 mNestedYOffset += mScrollOffset[1]; 3418 } 3419 } else { 3420 final boolean atOverscrollEdge = overScrollBy(0, overscroll, 3421 0, mScrollY, 0, 0, 0, mOverscrollDistance, true); 3422 3423 if (atOverscrollEdge && mVelocityTracker != null) { 3424 // Don't allow overfling if we're at the edge 3425 mVelocityTracker.clear(); 3426 } 3427 3428 final int overscrollMode = getOverScrollMode(); 3429 if (overscrollMode == OVER_SCROLL_ALWAYS || 3430 (overscrollMode == OVER_SCROLL_IF_CONTENT_SCROLLS && 3431 !contentFits())) { 3432 if (!atOverscrollEdge) { 3433 mDirection = 0; // Reset when entering overscroll. 3434 mTouchMode = TOUCH_MODE_OVERSCROLL; 3435 } 3436 if (incrementalDeltaY > 0) { 3437 mEdgeGlowTop.onPull((float) -overscroll / getHeight(), 3438 (float) x / getWidth()); 3439 if (!mEdgeGlowBottom.isFinished()) { 3440 mEdgeGlowBottom.onRelease(); 3441 } 3442 invalidate(0, 0, getWidth(), 3443 mEdgeGlowTop.getMaxHeight() + getPaddingTop()); 3444 } else if (incrementalDeltaY < 0) { 3445 mEdgeGlowBottom.onPull((float) overscroll / getHeight(), 3446 1.f - (float) x / getWidth()); 3447 if (!mEdgeGlowTop.isFinished()) { 3448 mEdgeGlowTop.onRelease(); 3449 } 3450 invalidate(0, getHeight() - getPaddingBottom() - 3451 mEdgeGlowBottom.getMaxHeight(), getWidth(), 3452 getHeight()); 3453 } 3454 } 3455 } 3456 } 3457 mMotionY = y + lastYCorrection + scrollOffsetCorrection; 3458 } 3459 mLastY = y + lastYCorrection + scrollOffsetCorrection; 3460 } 3461 } else if (mTouchMode == TOUCH_MODE_OVERSCROLL) { 3462 if (y != mLastY) { 3463 final int oldScroll = mScrollY; 3464 final int newScroll = oldScroll - incrementalDeltaY; 3465 int newDirection = y > mLastY ? 1 : -1; 3466 3467 if (mDirection == 0) { 3468 mDirection = newDirection; 3469 } 3470 3471 int overScrollDistance = -incrementalDeltaY; 3472 if ((newScroll < 0 && oldScroll >= 0) || (newScroll > 0 && oldScroll <= 0)) { 3473 overScrollDistance = -oldScroll; 3474 incrementalDeltaY += overScrollDistance; 3475 } else { 3476 incrementalDeltaY = 0; 3477 } 3478 3479 if (overScrollDistance != 0) { 3480 overScrollBy(0, overScrollDistance, 0, mScrollY, 0, 0, 3481 0, mOverscrollDistance, true); 3482 final int overscrollMode = getOverScrollMode(); 3483 if (overscrollMode == OVER_SCROLL_ALWAYS || 3484 (overscrollMode == OVER_SCROLL_IF_CONTENT_SCROLLS && 3485 !contentFits())) { 3486 if (rawDeltaY > 0) { 3487 mEdgeGlowTop.onPull((float) overScrollDistance / getHeight(), 3488 (float) x / getWidth()); 3489 if (!mEdgeGlowBottom.isFinished()) { 3490 mEdgeGlowBottom.onRelease(); 3491 } 3492 invalidate(0, 0, getWidth(), 3493 mEdgeGlowTop.getMaxHeight() + getPaddingTop()); 3494 } else if (rawDeltaY < 0) { 3495 mEdgeGlowBottom.onPull((float) overScrollDistance / getHeight(), 3496 1.f - (float) x / getWidth()); 3497 if (!mEdgeGlowTop.isFinished()) { 3498 mEdgeGlowTop.onRelease(); 3499 } 3500 invalidate(0, getHeight() - getPaddingBottom() - 3501 mEdgeGlowBottom.getMaxHeight(), getWidth(), 3502 getHeight()); 3503 } 3504 } 3505 } 3506 3507 if (incrementalDeltaY != 0) { 3508 // Coming back to 'real' list scrolling 3509 if (mScrollY != 0) { 3510 mScrollY = 0; 3511 invalidateParentIfNeeded(); 3512 } 3513 3514 trackMotionScroll(incrementalDeltaY, incrementalDeltaY); 3515 3516 mTouchMode = TOUCH_MODE_SCROLL; 3517 3518 // We did not scroll the full amount. Treat this essentially like the 3519 // start of a new touch scroll 3520 final int motionPosition = findClosestMotionRow(y); 3521 3522 mMotionCorrection = 0; 3523 View motionView = getChildAt(motionPosition - mFirstPosition); 3524 mMotionViewOriginalTop = motionView != null ? motionView.getTop() : 0; 3525 mMotionY = y + scrollOffsetCorrection; 3526 mMotionPosition = motionPosition; 3527 } 3528 mLastY = y + lastYCorrection + scrollOffsetCorrection; 3529 mDirection = newDirection; 3530 } 3531 } 3532 } 3533 3534 @Override 3535 public void onTouchModeChanged(boolean isInTouchMode) { 3536 if (isInTouchMode) { 3537 // Get rid of the selection when we enter touch mode 3538 hideSelector(); 3539 // Layout, but only if we already have done so previously. 3540 // (Otherwise may clobber a LAYOUT_SYNC layout that was requested to restore 3541 // state.) 3542 if (getHeight() > 0 && getChildCount() > 0) { 3543 // We do not lose focus initiating a touch (since AbsListView is focusable in 3544 // touch mode). Force an initial layout to get rid of the selection. 3545 layoutChildren(); 3546 } 3547 updateSelectorState(); 3548 } else { 3549 int touchMode = mTouchMode; 3550 if (touchMode == TOUCH_MODE_OVERSCROLL || touchMode == TOUCH_MODE_OVERFLING) { 3551 if (mFlingRunnable != null) { 3552 mFlingRunnable.endFling(); 3553 } 3554 if (mPositionScroller != null) { 3555 mPositionScroller.stop(); 3556 } 3557 3558 if (mScrollY != 0) { 3559 mScrollY = 0; 3560 invalidateParentCaches(); 3561 finishGlows(); 3562 invalidate(); 3563 } 3564 } 3565 } 3566 } 3567 3568 @Override 3569 public boolean onTouchEvent(MotionEvent ev) { 3570 if (!isEnabled()) { 3571 // A disabled view that is clickable still consumes the touch 3572 // events, it just doesn't respond to them. 3573 return isClickable() || isLongClickable(); 3574 } 3575 3576 if (mPositionScroller != null) { 3577 mPositionScroller.stop(); 3578 } 3579 3580 if (mIsDetaching || !isAttachedToWindow()) { 3581 // Something isn't right. 3582 // Since we rely on being attached to get data set change notifications, 3583 // don't risk doing anything where we might try to resync and find things 3584 // in a bogus state. 3585 return false; 3586 } 3587 3588 startNestedScroll(SCROLL_AXIS_VERTICAL); 3589 3590 if (mFastScroll != null) { 3591 boolean intercepted = mFastScroll.onTouchEvent(ev); 3592 if (intercepted) { 3593 return true; 3594 } 3595 } 3596 3597 initVelocityTrackerIfNotExists(); 3598 final MotionEvent vtev = MotionEvent.obtain(ev); 3599 3600 final int actionMasked = ev.getActionMasked(); 3601 if (actionMasked == MotionEvent.ACTION_DOWN) { 3602 mNestedYOffset = 0; 3603 } 3604 vtev.offsetLocation(0, mNestedYOffset); 3605 switch (actionMasked) { 3606 case MotionEvent.ACTION_DOWN: { 3607 onTouchDown(ev); 3608 break; 3609 } 3610 3611 case MotionEvent.ACTION_MOVE: { 3612 onTouchMove(ev, vtev); 3613 break; 3614 } 3615 3616 case MotionEvent.ACTION_UP: { 3617 onTouchUp(ev); 3618 break; 3619 } 3620 3621 case MotionEvent.ACTION_CANCEL: { 3622 onTouchCancel(); 3623 break; 3624 } 3625 3626 case MotionEvent.ACTION_POINTER_UP: { 3627 onSecondaryPointerUp(ev); 3628 final int x = mMotionX; 3629 final int y = mMotionY; 3630 final int motionPosition = pointToPosition(x, y); 3631 if (motionPosition >= 0) { 3632 // Remember where the motion event started 3633 final View child = getChildAt(motionPosition - mFirstPosition); 3634 mMotionViewOriginalTop = child.getTop(); 3635 mMotionPosition = motionPosition; 3636 } 3637 mLastY = y; 3638 break; 3639 } 3640 3641 case MotionEvent.ACTION_POINTER_DOWN: { 3642 // New pointers take over dragging duties 3643 final int index = ev.getActionIndex(); 3644 final int id = ev.getPointerId(index); 3645 final int x = (int) ev.getX(index); 3646 final int y = (int) ev.getY(index); 3647 mMotionCorrection = 0; 3648 mActivePointerId = id; 3649 mMotionX = x; 3650 mMotionY = y; 3651 final int motionPosition = pointToPosition(x, y); 3652 if (motionPosition >= 0) { 3653 // Remember where the motion event started 3654 final View child = getChildAt(motionPosition - mFirstPosition); 3655 mMotionViewOriginalTop = child.getTop(); 3656 mMotionPosition = motionPosition; 3657 } 3658 mLastY = y; 3659 break; 3660 } 3661 } 3662 3663 if (mVelocityTracker != null) { 3664 mVelocityTracker.addMovement(vtev); 3665 } 3666 vtev.recycle(); 3667 return true; 3668 } 3669 3670 private void onTouchDown(MotionEvent ev) { 3671 mActivePointerId = ev.getPointerId(0); 3672 3673 if (mTouchMode == TOUCH_MODE_OVERFLING) { 3674 // Stopped the fling. It is a scroll. 3675 mFlingRunnable.endFling(); 3676 if (mPositionScroller != null) { 3677 mPositionScroller.stop(); 3678 } 3679 mTouchMode = TOUCH_MODE_OVERSCROLL; 3680 mMotionX = (int) ev.getX(); 3681 mMotionY = (int) ev.getY(); 3682 mLastY = mMotionY; 3683 mMotionCorrection = 0; 3684 mDirection = 0; 3685 } else { 3686 final int x = (int) ev.getX(); 3687 final int y = (int) ev.getY(); 3688 int motionPosition = pointToPosition(x, y); 3689 3690 if (!mDataChanged) { 3691 if (mTouchMode == TOUCH_MODE_FLING) { 3692 // Stopped a fling. It is a scroll. 3693 createScrollingCache(); 3694 mTouchMode = TOUCH_MODE_SCROLL; 3695 mMotionCorrection = 0; 3696 motionPosition = findMotionRow(y); 3697 mFlingRunnable.flywheelTouch(); 3698 } else if ((motionPosition >= 0) && getAdapter().isEnabled(motionPosition)) { 3699 // User clicked on an actual view (and was not stopping a 3700 // fling). It might be a click or a scroll. Assume it is a 3701 // click until proven otherwise. 3702 mTouchMode = TOUCH_MODE_DOWN; 3703 3704 // FIXME Debounce 3705 if (mPendingCheckForTap == null) { 3706 mPendingCheckForTap = new CheckForTap(); 3707 } 3708 3709 mPendingCheckForTap.x = ev.getX(); 3710 mPendingCheckForTap.y = ev.getY(); 3711 postDelayed(mPendingCheckForTap, ViewConfiguration.getTapTimeout()); 3712 } 3713 } 3714 3715 if (motionPosition >= 0) { 3716 // Remember where the motion event started 3717 final View v = getChildAt(motionPosition - mFirstPosition); 3718 mMotionViewOriginalTop = v.getTop(); 3719 } 3720 3721 mMotionX = x; 3722 mMotionY = y; 3723 mMotionPosition = motionPosition; 3724 mLastY = Integer.MIN_VALUE; 3725 } 3726 3727 if (mTouchMode == TOUCH_MODE_DOWN && mMotionPosition != INVALID_POSITION 3728 && performButtonActionOnTouchDown(ev)) { 3729 removeCallbacks(mPendingCheckForTap); 3730 } 3731 } 3732 3733 private void onTouchMove(MotionEvent ev, MotionEvent vtev) { 3734 int pointerIndex = ev.findPointerIndex(mActivePointerId); 3735 if (pointerIndex == -1) { 3736 pointerIndex = 0; 3737 mActivePointerId = ev.getPointerId(pointerIndex); 3738 } 3739 3740 if (mDataChanged) { 3741 // Re-sync everything if data has been changed 3742 // since the scroll operation can query the adapter. 3743 layoutChildren(); 3744 } 3745 3746 final int y = (int) ev.getY(pointerIndex); 3747 3748 switch (mTouchMode) { 3749 case TOUCH_MODE_DOWN: 3750 case TOUCH_MODE_TAP: 3751 case TOUCH_MODE_DONE_WAITING: 3752 // Check if we have moved far enough that it looks more like a 3753 // scroll than a tap. If so, we'll enter scrolling mode. 3754 if (startScrollIfNeeded((int) ev.getX(pointerIndex), y, vtev)) { 3755 break; 3756 } 3757 // Otherwise, check containment within list bounds. If we're 3758 // outside bounds, cancel any active presses. 3759 final float x = ev.getX(pointerIndex); 3760 if (!pointInView(x, y, mTouchSlop)) { 3761 setPressed(false); 3762 final View motionView = getChildAt(mMotionPosition - mFirstPosition); 3763 if (motionView != null) { 3764 motionView.setPressed(false); 3765 } 3766 removeCallbacks(mTouchMode == TOUCH_MODE_DOWN ? 3767 mPendingCheckForTap : mPendingCheckForLongPress); 3768 mTouchMode = TOUCH_MODE_DONE_WAITING; 3769 updateSelectorState(); 3770 } 3771 break; 3772 case TOUCH_MODE_SCROLL: 3773 case TOUCH_MODE_OVERSCROLL: 3774 scrollIfNeeded((int) ev.getX(pointerIndex), y, vtev); 3775 break; 3776 } 3777 } 3778 3779 private void onTouchUp(MotionEvent ev) { 3780 switch (mTouchMode) { 3781 case TOUCH_MODE_DOWN: 3782 case TOUCH_MODE_TAP: 3783 case TOUCH_MODE_DONE_WAITING: 3784 final int motionPosition = mMotionPosition; 3785 final View child = getChildAt(motionPosition - mFirstPosition); 3786 if (child != null) { 3787 if (mTouchMode != TOUCH_MODE_DOWN) { 3788 child.setPressed(false); 3789 } 3790 3791 final float x = ev.getX(); 3792 final boolean inList = x > mListPadding.left && x < getWidth() - mListPadding.right; 3793 if (inList && !child.hasFocusable()) { 3794 if (mPerformClick == null) { 3795 mPerformClick = new PerformClick(); 3796 } 3797 3798 final AbsListView.PerformClick performClick = mPerformClick; 3799 performClick.mClickMotionPosition = motionPosition; 3800 performClick.rememberWindowAttachCount(); 3801 3802 mResurrectToPosition = motionPosition; 3803 3804 if (mTouchMode == TOUCH_MODE_DOWN || mTouchMode == TOUCH_MODE_TAP) { 3805 removeCallbacks(mTouchMode == TOUCH_MODE_DOWN ? 3806 mPendingCheckForTap : mPendingCheckForLongPress); 3807 mLayoutMode = LAYOUT_NORMAL; 3808 if (!mDataChanged && mAdapter.isEnabled(motionPosition)) { 3809 mTouchMode = TOUCH_MODE_TAP; 3810 setSelectedPositionInt(mMotionPosition); 3811 layoutChildren(); 3812 child.setPressed(true); 3813 positionSelector(mMotionPosition, child); 3814 setPressed(true); 3815 if (mSelector != null) { 3816 Drawable d = mSelector.getCurrent(); 3817 if (d != null && d instanceof TransitionDrawable) { 3818 ((TransitionDrawable) d).resetTransition(); 3819 } 3820 mSelector.setHotspot(x, ev.getY()); 3821 } 3822 if (mTouchModeReset != null) { 3823 removeCallbacks(mTouchModeReset); 3824 } 3825 mTouchModeReset = new Runnable() { 3826 @Override 3827 public void run() { 3828 mTouchModeReset = null; 3829 mTouchMode = TOUCH_MODE_REST; 3830 child.setPressed(false); 3831 setPressed(false); 3832 if (!mDataChanged && !mIsDetaching && isAttachedToWindow()) { 3833 performClick.run(); 3834 } 3835 } 3836 }; 3837 postDelayed(mTouchModeReset, 3838 ViewConfiguration.getPressedStateDuration()); 3839 } else { 3840 mTouchMode = TOUCH_MODE_REST; 3841 updateSelectorState(); 3842 } 3843 return; 3844 } else if (!mDataChanged && mAdapter.isEnabled(motionPosition)) { 3845 performClick.run(); 3846 } 3847 } 3848 } 3849 mTouchMode = TOUCH_MODE_REST; 3850 updateSelectorState(); 3851 break; 3852 case TOUCH_MODE_SCROLL: 3853 final int childCount = getChildCount(); 3854 if (childCount > 0) { 3855 final int firstChildTop = getChildAt(0).getTop(); 3856 final int lastChildBottom = getChildAt(childCount - 1).getBottom(); 3857 final int contentTop = mListPadding.top; 3858 final int contentBottom = getHeight() - mListPadding.bottom; 3859 if (mFirstPosition == 0 && firstChildTop >= contentTop && 3860 mFirstPosition + childCount < mItemCount && 3861 lastChildBottom <= getHeight() - contentBottom) { 3862 mTouchMode = TOUCH_MODE_REST; 3863 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 3864 } else { 3865 final VelocityTracker velocityTracker = mVelocityTracker; 3866 velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity); 3867 3868 final int initialVelocity = (int) 3869 (velocityTracker.getYVelocity(mActivePointerId) * mVelocityScale); 3870 // Fling if we have enough velocity and we aren't at a boundary. 3871 // Since we can potentially overfling more than we can overscroll, don't 3872 // allow the weird behavior where you can scroll to a boundary then 3873 // fling further. 3874 boolean flingVelocity = Math.abs(initialVelocity) > mMinimumVelocity; 3875 if (flingVelocity && 3876 !((mFirstPosition == 0 && 3877 firstChildTop == contentTop - mOverscrollDistance) || 3878 (mFirstPosition + childCount == mItemCount && 3879 lastChildBottom == contentBottom + mOverscrollDistance))) { 3880 if (!dispatchNestedPreFling(0, -initialVelocity)) { 3881 if (mFlingRunnable == null) { 3882 mFlingRunnable = new FlingRunnable(); 3883 } 3884 reportScrollStateChange(OnScrollListener.SCROLL_STATE_FLING); 3885 mFlingRunnable.start(-initialVelocity); 3886 dispatchNestedFling(0, -initialVelocity, true); 3887 } else { 3888 mTouchMode = TOUCH_MODE_REST; 3889 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 3890 } 3891 } else { 3892 mTouchMode = TOUCH_MODE_REST; 3893 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 3894 if (mFlingRunnable != null) { 3895 mFlingRunnable.endFling(); 3896 } 3897 if (mPositionScroller != null) { 3898 mPositionScroller.stop(); 3899 } 3900 if (flingVelocity && !dispatchNestedPreFling(0, -initialVelocity)) { 3901 dispatchNestedFling(0, -initialVelocity, false); 3902 } 3903 } 3904 } 3905 } else { 3906 mTouchMode = TOUCH_MODE_REST; 3907 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 3908 } 3909 break; 3910 3911 case TOUCH_MODE_OVERSCROLL: 3912 if (mFlingRunnable == null) { 3913 mFlingRunnable = new FlingRunnable(); 3914 } 3915 final VelocityTracker velocityTracker = mVelocityTracker; 3916 velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity); 3917 final int initialVelocity = (int) velocityTracker.getYVelocity(mActivePointerId); 3918 3919 reportScrollStateChange(OnScrollListener.SCROLL_STATE_FLING); 3920 if (Math.abs(initialVelocity) > mMinimumVelocity) { 3921 mFlingRunnable.startOverfling(-initialVelocity); 3922 } else { 3923 mFlingRunnable.startSpringback(); 3924 } 3925 3926 break; 3927 } 3928 3929 setPressed(false); 3930 3931 if (mEdgeGlowTop != null) { 3932 mEdgeGlowTop.onRelease(); 3933 mEdgeGlowBottom.onRelease(); 3934 } 3935 3936 // Need to redraw since we probably aren't drawing the selector anymore 3937 invalidate(); 3938 removeCallbacks(mPendingCheckForLongPress); 3939 recycleVelocityTracker(); 3940 3941 mActivePointerId = INVALID_POINTER; 3942 3943 if (PROFILE_SCROLLING) { 3944 if (mScrollProfilingStarted) { 3945 Debug.stopMethodTracing(); 3946 mScrollProfilingStarted = false; 3947 } 3948 } 3949 3950 if (mScrollStrictSpan != null) { 3951 mScrollStrictSpan.finish(); 3952 mScrollStrictSpan = null; 3953 } 3954 } 3955 3956 private void onTouchCancel() { 3957 switch (mTouchMode) { 3958 case TOUCH_MODE_OVERSCROLL: 3959 if (mFlingRunnable == null) { 3960 mFlingRunnable = new FlingRunnable(); 3961 } 3962 mFlingRunnable.startSpringback(); 3963 break; 3964 3965 case TOUCH_MODE_OVERFLING: 3966 // Do nothing - let it play out. 3967 break; 3968 3969 default: 3970 mTouchMode = TOUCH_MODE_REST; 3971 setPressed(false); 3972 final View motionView = this.getChildAt(mMotionPosition - mFirstPosition); 3973 if (motionView != null) { 3974 motionView.setPressed(false); 3975 } 3976 clearScrollingCache(); 3977 removeCallbacks(mPendingCheckForLongPress); 3978 recycleVelocityTracker(); 3979 } 3980 3981 if (mEdgeGlowTop != null) { 3982 mEdgeGlowTop.onRelease(); 3983 mEdgeGlowBottom.onRelease(); 3984 } 3985 mActivePointerId = INVALID_POINTER; 3986 } 3987 3988 @Override 3989 protected void onOverScrolled(int scrollX, int scrollY, boolean clampedX, boolean clampedY) { 3990 if (mScrollY != scrollY) { 3991 onScrollChanged(mScrollX, scrollY, mScrollX, mScrollY); 3992 mScrollY = scrollY; 3993 invalidateParentIfNeeded(); 3994 3995 awakenScrollBars(); 3996 } 3997 } 3998 3999 @Override 4000 public boolean onGenericMotionEvent(MotionEvent event) { 4001 if ((event.getSource() & InputDevice.SOURCE_CLASS_POINTER) != 0) { 4002 switch (event.getAction()) { 4003 case MotionEvent.ACTION_SCROLL: { 4004 if (mTouchMode == TOUCH_MODE_REST) { 4005 final float vscroll = event.getAxisValue(MotionEvent.AXIS_VSCROLL); 4006 if (vscroll != 0) { 4007 final int delta = (int) (vscroll * getVerticalScrollFactor()); 4008 if (!trackMotionScroll(delta, delta)) { 4009 return true; 4010 } 4011 } 4012 } 4013 } 4014 } 4015 } 4016 return super.onGenericMotionEvent(event); 4017 } 4018 4019 /** 4020 * Initiate a fling with the given velocity. 4021 * 4022 * <p>Applications can use this method to manually initiate a fling as if the user 4023 * initiated it via touch interaction.</p> 4024 * 4025 * @param velocityY Vertical velocity in pixels per second. Note that this is velocity of 4026 * content, not velocity of a touch that initiated the fling. 4027 */ 4028 public void fling(int velocityY) { 4029 if (mFlingRunnable == null) { 4030 mFlingRunnable = new FlingRunnable(); 4031 } 4032 reportScrollStateChange(OnScrollListener.SCROLL_STATE_FLING); 4033 mFlingRunnable.start(velocityY); 4034 } 4035 4036 @Override 4037 public boolean onStartNestedScroll(View child, View target, int nestedScrollAxes) { 4038 return ((nestedScrollAxes & SCROLL_AXIS_VERTICAL) != 0); 4039 } 4040 4041 @Override 4042 public void onNestedScrollAccepted(View child, View target, int axes) { 4043 super.onNestedScrollAccepted(child, target, axes); 4044 startNestedScroll(SCROLL_AXIS_VERTICAL); 4045 } 4046 4047 @Override 4048 public void onNestedScroll(View target, int dxConsumed, int dyConsumed, 4049 int dxUnconsumed, int dyUnconsumed) { 4050 final int motionIndex = getChildCount() / 2; 4051 final View motionView = getChildAt(motionIndex); 4052 final int oldTop = motionView != null ? motionView.getTop() : 0; 4053 if (motionView == null || trackMotionScroll(-dyUnconsumed, -dyUnconsumed)) { 4054 int myUnconsumed = dyUnconsumed; 4055 int myConsumed = 0; 4056 if (motionView != null) { 4057 myConsumed = motionView.getTop() - oldTop; 4058 myUnconsumed -= myConsumed; 4059 } 4060 dispatchNestedScroll(0, myConsumed, 0, myUnconsumed, null); 4061 } 4062 } 4063 4064 @Override 4065 public boolean onNestedFling(View target, float velocityX, float velocityY, boolean consumed) { 4066 final int childCount = getChildCount(); 4067 if (!consumed && childCount > 0 && canScrollList((int) velocityY) && 4068 Math.abs(velocityY) > mMinimumVelocity) { 4069 reportScrollStateChange(OnScrollListener.SCROLL_STATE_FLING); 4070 if (mFlingRunnable == null) { 4071 mFlingRunnable = new FlingRunnable(); 4072 } 4073 if (!dispatchNestedPreFling(0, velocityY)) { 4074 mFlingRunnable.start((int) velocityY); 4075 } 4076 return true; 4077 } 4078 return dispatchNestedFling(velocityX, velocityY, consumed); 4079 } 4080 4081 @Override 4082 public void draw(Canvas canvas) { 4083 super.draw(canvas); 4084 if (mEdgeGlowTop != null) { 4085 final int scrollY = mScrollY; 4086 if (!mEdgeGlowTop.isFinished()) { 4087 final int restoreCount = canvas.save(); 4088 final int width = getWidth(); 4089 4090 int edgeY = Math.min(0, scrollY + mFirstPositionDistanceGuess); 4091 canvas.translate(0, edgeY); 4092 mEdgeGlowTop.setSize(width, getHeight()); 4093 if (mEdgeGlowTop.draw(canvas)) { 4094 invalidate(0, 0, getWidth(), 4095 mEdgeGlowTop.getMaxHeight() + getPaddingTop()); 4096 } 4097 canvas.restoreToCount(restoreCount); 4098 } 4099 if (!mEdgeGlowBottom.isFinished()) { 4100 final int restoreCount = canvas.save(); 4101 final int width = getWidth(); 4102 final int height = getHeight(); 4103 4104 int edgeX = -width; 4105 int edgeY = Math.max(height, scrollY + mLastPositionDistanceGuess); 4106 canvas.translate(edgeX, edgeY); 4107 canvas.rotate(180, width, 0); 4108 mEdgeGlowBottom.setSize(width, height); 4109 if (mEdgeGlowBottom.draw(canvas)) { 4110 invalidate(0, getHeight() - getPaddingBottom() - 4111 mEdgeGlowBottom.getMaxHeight(), getWidth(), 4112 getHeight()); 4113 } 4114 canvas.restoreToCount(restoreCount); 4115 } 4116 } 4117 } 4118 4119 /** 4120 * @hide 4121 */ 4122 public void setOverScrollEffectPadding(int leftPadding, int rightPadding) { 4123 mGlowPaddingLeft = leftPadding; 4124 mGlowPaddingRight = rightPadding; 4125 } 4126 4127 private void initOrResetVelocityTracker() { 4128 if (mVelocityTracker == null) { 4129 mVelocityTracker = VelocityTracker.obtain(); 4130 } else { 4131 mVelocityTracker.clear(); 4132 } 4133 } 4134 4135 private void initVelocityTrackerIfNotExists() { 4136 if (mVelocityTracker == null) { 4137 mVelocityTracker = VelocityTracker.obtain(); 4138 } 4139 } 4140 4141 private void recycleVelocityTracker() { 4142 if (mVelocityTracker != null) { 4143 mVelocityTracker.recycle(); 4144 mVelocityTracker = null; 4145 } 4146 } 4147 4148 @Override 4149 public void requestDisallowInterceptTouchEvent(boolean disallowIntercept) { 4150 if (disallowIntercept) { 4151 recycleVelocityTracker(); 4152 } 4153 super.requestDisallowInterceptTouchEvent(disallowIntercept); 4154 } 4155 4156 @Override 4157 public boolean onInterceptHoverEvent(MotionEvent event) { 4158 if (mFastScroll != null && mFastScroll.onInterceptHoverEvent(event)) { 4159 return true; 4160 } 4161 4162 return super.onInterceptHoverEvent(event); 4163 } 4164 4165 @Override 4166 public boolean onInterceptTouchEvent(MotionEvent ev) { 4167 final int actionMasked = ev.getActionMasked(); 4168 View v; 4169 4170 if (mPositionScroller != null) { 4171 mPositionScroller.stop(); 4172 } 4173 4174 if (mIsDetaching || !isAttachedToWindow()) { 4175 // Something isn't right. 4176 // Since we rely on being attached to get data set change notifications, 4177 // don't risk doing anything where we might try to resync and find things 4178 // in a bogus state. 4179 return false; 4180 } 4181 4182 if (mFastScroll != null && mFastScroll.onInterceptTouchEvent(ev)) { 4183 return true; 4184 } 4185 4186 switch (actionMasked) { 4187 case MotionEvent.ACTION_DOWN: { 4188 int touchMode = mTouchMode; 4189 if (touchMode == TOUCH_MODE_OVERFLING || touchMode == TOUCH_MODE_OVERSCROLL) { 4190 mMotionCorrection = 0; 4191 return true; 4192 } 4193 4194 final int x = (int) ev.getX(); 4195 final int y = (int) ev.getY(); 4196 mActivePointerId = ev.getPointerId(0); 4197 4198 int motionPosition = findMotionRow(y); 4199 if (touchMode != TOUCH_MODE_FLING && motionPosition >= 0) { 4200 // User clicked on an actual view (and was not stopping a fling). 4201 // Remember where the motion event started 4202 v = getChildAt(motionPosition - mFirstPosition); 4203 mMotionViewOriginalTop = v.getTop(); 4204 mMotionX = x; 4205 mMotionY = y; 4206 mMotionPosition = motionPosition; 4207 mTouchMode = TOUCH_MODE_DOWN; 4208 clearScrollingCache(); 4209 } 4210 mLastY = Integer.MIN_VALUE; 4211 initOrResetVelocityTracker(); 4212 mVelocityTracker.addMovement(ev); 4213 mNestedYOffset = 0; 4214 startNestedScroll(SCROLL_AXIS_VERTICAL); 4215 if (touchMode == TOUCH_MODE_FLING) { 4216 return true; 4217 } 4218 break; 4219 } 4220 4221 case MotionEvent.ACTION_MOVE: { 4222 switch (mTouchMode) { 4223 case TOUCH_MODE_DOWN: 4224 int pointerIndex = ev.findPointerIndex(mActivePointerId); 4225 if (pointerIndex == -1) { 4226 pointerIndex = 0; 4227 mActivePointerId = ev.getPointerId(pointerIndex); 4228 } 4229 final int y = (int) ev.getY(pointerIndex); 4230 initVelocityTrackerIfNotExists(); 4231 mVelocityTracker.addMovement(ev); 4232 if (startScrollIfNeeded((int) ev.getX(pointerIndex), y, null)) { 4233 return true; 4234 } 4235 break; 4236 } 4237 break; 4238 } 4239 4240 case MotionEvent.ACTION_CANCEL: 4241 case MotionEvent.ACTION_UP: { 4242 mTouchMode = TOUCH_MODE_REST; 4243 mActivePointerId = INVALID_POINTER; 4244 recycleVelocityTracker(); 4245 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 4246 stopNestedScroll(); 4247 break; 4248 } 4249 4250 case MotionEvent.ACTION_POINTER_UP: { 4251 onSecondaryPointerUp(ev); 4252 break; 4253 } 4254 } 4255 4256 return false; 4257 } 4258 4259 private void onSecondaryPointerUp(MotionEvent ev) { 4260 final int pointerIndex = (ev.getAction() & MotionEvent.ACTION_POINTER_INDEX_MASK) >> 4261 MotionEvent.ACTION_POINTER_INDEX_SHIFT; 4262 final int pointerId = ev.getPointerId(pointerIndex); 4263 if (pointerId == mActivePointerId) { 4264 // This was our active pointer going up. Choose a new 4265 // active pointer and adjust accordingly. 4266 // TODO: Make this decision more intelligent. 4267 final int newPointerIndex = pointerIndex == 0 ? 1 : 0; 4268 mMotionX = (int) ev.getX(newPointerIndex); 4269 mMotionY = (int) ev.getY(newPointerIndex); 4270 mMotionCorrection = 0; 4271 mActivePointerId = ev.getPointerId(newPointerIndex); 4272 } 4273 } 4274 4275 /** 4276 * {@inheritDoc} 4277 */ 4278 @Override 4279 public void addTouchables(ArrayList<View> views) { 4280 final int count = getChildCount(); 4281 final int firstPosition = mFirstPosition; 4282 final ListAdapter adapter = mAdapter; 4283 4284 if (adapter == null) { 4285 return; 4286 } 4287 4288 for (int i = 0; i < count; i++) { 4289 final View child = getChildAt(i); 4290 if (adapter.isEnabled(firstPosition + i)) { 4291 views.add(child); 4292 } 4293 child.addTouchables(views); 4294 } 4295 } 4296 4297 /** 4298 * Fires an "on scroll state changed" event to the registered 4299 * {@link android.widget.AbsListView.OnScrollListener}, if any. The state change 4300 * is fired only if the specified state is different from the previously known state. 4301 * 4302 * @param newState The new scroll state. 4303 */ 4304 void reportScrollStateChange(int newState) { 4305 if (newState != mLastScrollState) { 4306 if (mOnScrollListener != null) { 4307 mLastScrollState = newState; 4308 mOnScrollListener.onScrollStateChanged(this, newState); 4309 } 4310 } 4311 } 4312 4313 /** 4314 * Responsible for fling behavior. Use {@link #start(int)} to 4315 * initiate a fling. Each frame of the fling is handled in {@link #run()}. 4316 * A FlingRunnable will keep re-posting itself until the fling is done. 4317 * 4318 */ 4319 private class FlingRunnable implements Runnable { 4320 /** 4321 * Tracks the decay of a fling scroll 4322 */ 4323 private final OverScroller mScroller; 4324 4325 /** 4326 * Y value reported by mScroller on the previous fling 4327 */ 4328 private int mLastFlingY; 4329 4330 private final Runnable mCheckFlywheel = new Runnable() { 4331 @Override 4332 public void run() { 4333 final int activeId = mActivePointerId; 4334 final VelocityTracker vt = mVelocityTracker; 4335 final OverScroller scroller = mScroller; 4336 if (vt == null || activeId == INVALID_POINTER) { 4337 return; 4338 } 4339 4340 vt.computeCurrentVelocity(1000, mMaximumVelocity); 4341 final float yvel = -vt.getYVelocity(activeId); 4342 4343 if (Math.abs(yvel) >= mMinimumVelocity 4344 && scroller.isScrollingInDirection(0, yvel)) { 4345 // Keep the fling alive a little longer 4346 postDelayed(this, FLYWHEEL_TIMEOUT); 4347 } else { 4348 endFling(); 4349 mTouchMode = TOUCH_MODE_SCROLL; 4350 reportScrollStateChange(OnScrollListener.SCROLL_STATE_TOUCH_SCROLL); 4351 } 4352 } 4353 }; 4354 4355 private static final int FLYWHEEL_TIMEOUT = 40; // milliseconds 4356 4357 FlingRunnable() { 4358 mScroller = new OverScroller(getContext()); 4359 } 4360 4361 void start(int initialVelocity) { 4362 int initialY = initialVelocity < 0 ? Integer.MAX_VALUE : 0; 4363 mLastFlingY = initialY; 4364 mScroller.setInterpolator(null); 4365 mScroller.fling(0, initialY, 0, initialVelocity, 4366 0, Integer.MAX_VALUE, 0, Integer.MAX_VALUE); 4367 mTouchMode = TOUCH_MODE_FLING; 4368 postOnAnimation(this); 4369 4370 if (PROFILE_FLINGING) { 4371 if (!mFlingProfilingStarted) { 4372 Debug.startMethodTracing("AbsListViewFling"); 4373 mFlingProfilingStarted = true; 4374 } 4375 } 4376 4377 if (mFlingStrictSpan == null) { 4378 mFlingStrictSpan = StrictMode.enterCriticalSpan("AbsListView-fling"); 4379 } 4380 } 4381 4382 void startSpringback() { 4383 if (mScroller.springBack(0, mScrollY, 0, 0, 0, 0)) { 4384 mTouchMode = TOUCH_MODE_OVERFLING; 4385 invalidate(); 4386 postOnAnimation(this); 4387 } else { 4388 mTouchMode = TOUCH_MODE_REST; 4389 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 4390 } 4391 } 4392 4393 void startOverfling(int initialVelocity) { 4394 mScroller.setInterpolator(null); 4395 mScroller.fling(0, mScrollY, 0, initialVelocity, 0, 0, 4396 Integer.MIN_VALUE, Integer.MAX_VALUE, 0, getHeight()); 4397 mTouchMode = TOUCH_MODE_OVERFLING; 4398 invalidate(); 4399 postOnAnimation(this); 4400 } 4401 4402 void edgeReached(int delta) { 4403 mScroller.notifyVerticalEdgeReached(mScrollY, 0, mOverflingDistance); 4404 final int overscrollMode = getOverScrollMode(); 4405 if (overscrollMode == OVER_SCROLL_ALWAYS || 4406 (overscrollMode == OVER_SCROLL_IF_CONTENT_SCROLLS && !contentFits())) { 4407 mTouchMode = TOUCH_MODE_OVERFLING; 4408 final int vel = (int) mScroller.getCurrVelocity(); 4409 if (delta > 0) { 4410 mEdgeGlowTop.onAbsorb(vel); 4411 } else { 4412 mEdgeGlowBottom.onAbsorb(vel); 4413 } 4414 } else { 4415 mTouchMode = TOUCH_MODE_REST; 4416 if (mPositionScroller != null) { 4417 mPositionScroller.stop(); 4418 } 4419 } 4420 invalidate(); 4421 postOnAnimation(this); 4422 } 4423 4424 void startScroll(int distance, int duration, boolean linear) { 4425 int initialY = distance < 0 ? Integer.MAX_VALUE : 0; 4426 mLastFlingY = initialY; 4427 mScroller.setInterpolator(linear ? sLinearInterpolator : null); 4428 mScroller.startScroll(0, initialY, 0, distance, duration); 4429 mTouchMode = TOUCH_MODE_FLING; 4430 postOnAnimation(this); 4431 } 4432 4433 void endFling() { 4434 mTouchMode = TOUCH_MODE_REST; 4435 4436 removeCallbacks(this); 4437 removeCallbacks(mCheckFlywheel); 4438 4439 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 4440 clearScrollingCache(); 4441 mScroller.abortAnimation(); 4442 4443 if (mFlingStrictSpan != null) { 4444 mFlingStrictSpan.finish(); 4445 mFlingStrictSpan = null; 4446 } 4447 } 4448 4449 void flywheelTouch() { 4450 postDelayed(mCheckFlywheel, FLYWHEEL_TIMEOUT); 4451 } 4452 4453 @Override 4454 public void run() { 4455 switch (mTouchMode) { 4456 default: 4457 endFling(); 4458 return; 4459 4460 case TOUCH_MODE_SCROLL: 4461 if (mScroller.isFinished()) { 4462 return; 4463 } 4464 // Fall through 4465 case TOUCH_MODE_FLING: { 4466 if (mDataChanged) { 4467 layoutChildren(); 4468 } 4469 4470 if (mItemCount == 0 || getChildCount() == 0) { 4471 endFling(); 4472 return; 4473 } 4474 4475 final OverScroller scroller = mScroller; 4476 boolean more = scroller.computeScrollOffset(); 4477 final int y = scroller.getCurrY(); 4478 4479 // Flip sign to convert finger direction to list items direction 4480 // (e.g. finger moving down means list is moving towards the top) 4481 int delta = mLastFlingY - y; 4482 4483 // Pretend that each frame of a fling scroll is a touch scroll 4484 if (delta > 0) { 4485 // List is moving towards the top. Use first view as mMotionPosition 4486 mMotionPosition = mFirstPosition; 4487 final View firstView = getChildAt(0); 4488 mMotionViewOriginalTop = firstView.getTop(); 4489 4490 // Don't fling more than 1 screen 4491 delta = Math.min(getHeight() - mPaddingBottom - mPaddingTop - 1, delta); 4492 } else { 4493 // List is moving towards the bottom. Use last view as mMotionPosition 4494 int offsetToLast = getChildCount() - 1; 4495 mMotionPosition = mFirstPosition + offsetToLast; 4496 4497 final View lastView = getChildAt(offsetToLast); 4498 mMotionViewOriginalTop = lastView.getTop(); 4499 4500 // Don't fling more than 1 screen 4501 delta = Math.max(-(getHeight() - mPaddingBottom - mPaddingTop - 1), delta); 4502 } 4503 4504 // Check to see if we have bumped into the scroll limit 4505 View motionView = getChildAt(mMotionPosition - mFirstPosition); 4506 int oldTop = 0; 4507 if (motionView != null) { 4508 oldTop = motionView.getTop(); 4509 } 4510 4511 // Don't stop just because delta is zero (it could have been rounded) 4512 final boolean atEdge = trackMotionScroll(delta, delta); 4513 final boolean atEnd = atEdge && (delta != 0); 4514 if (atEnd) { 4515 if (motionView != null) { 4516 // Tweak the scroll for how far we overshot 4517 int overshoot = -(delta - (motionView.getTop() - oldTop)); 4518 overScrollBy(0, overshoot, 0, mScrollY, 0, 0, 4519 0, mOverflingDistance, false); 4520 } 4521 if (more) { 4522 edgeReached(delta); 4523 } 4524 break; 4525 } 4526 4527 if (more && !atEnd) { 4528 if (atEdge) invalidate(); 4529 mLastFlingY = y; 4530 postOnAnimation(this); 4531 } else { 4532 endFling(); 4533 4534 if (PROFILE_FLINGING) { 4535 if (mFlingProfilingStarted) { 4536 Debug.stopMethodTracing(); 4537 mFlingProfilingStarted = false; 4538 } 4539 4540 if (mFlingStrictSpan != null) { 4541 mFlingStrictSpan.finish(); 4542 mFlingStrictSpan = null; 4543 } 4544 } 4545 } 4546 break; 4547 } 4548 4549 case TOUCH_MODE_OVERFLING: { 4550 final OverScroller scroller = mScroller; 4551 if (scroller.computeScrollOffset()) { 4552 final int scrollY = mScrollY; 4553 final int currY = scroller.getCurrY(); 4554 final int deltaY = currY - scrollY; 4555 if (overScrollBy(0, deltaY, 0, scrollY, 0, 0, 4556 0, mOverflingDistance, false)) { 4557 final boolean crossDown = scrollY <= 0 && currY > 0; 4558 final boolean crossUp = scrollY >= 0 && currY < 0; 4559 if (crossDown || crossUp) { 4560 int velocity = (int) scroller.getCurrVelocity(); 4561 if (crossUp) velocity = -velocity; 4562 4563 // Don't flywheel from this; we're just continuing things. 4564 scroller.abortAnimation(); 4565 start(velocity); 4566 } else { 4567 startSpringback(); 4568 } 4569 } else { 4570 invalidate(); 4571 postOnAnimation(this); 4572 } 4573 } else { 4574 endFling(); 4575 } 4576 break; 4577 } 4578 } 4579 } 4580 } 4581 4582 /** 4583 * The amount of friction applied to flings. The default value 4584 * is {@link ViewConfiguration#getScrollFriction}. 4585 */ 4586 public void setFriction(float friction) { 4587 if (mFlingRunnable == null) { 4588 mFlingRunnable = new FlingRunnable(); 4589 } 4590 mFlingRunnable.mScroller.setFriction(friction); 4591 } 4592 4593 /** 4594 * Sets a scale factor for the fling velocity. The initial scale 4595 * factor is 1.0. 4596 * 4597 * @param scale The scale factor to multiply the velocity by. 4598 */ 4599 public void setVelocityScale(float scale) { 4600 mVelocityScale = scale; 4601 } 4602 4603 /** 4604 * Override this for better control over position scrolling. 4605 */ 4606 AbsPositionScroller createPositionScroller() { 4607 return new PositionScroller(); 4608 } 4609 4610 /** 4611 * Smoothly scroll to the specified adapter position. The view will 4612 * scroll such that the indicated position is displayed. 4613 * @param position Scroll to this adapter position. 4614 */ 4615 public void smoothScrollToPosition(int position) { 4616 if (mPositionScroller == null) { 4617 mPositionScroller = createPositionScroller(); 4618 } 4619 mPositionScroller.start(position); 4620 } 4621 4622 /** 4623 * Smoothly scroll to the specified adapter position. The view will scroll 4624 * such that the indicated position is displayed <code>offset</code> pixels below 4625 * the top edge of the view. If this is impossible, (e.g. the offset would scroll 4626 * the first or last item beyond the boundaries of the list) it will get as close 4627 * as possible. The scroll will take <code>duration</code> milliseconds to complete. 4628 * 4629 * @param position Position to scroll to 4630 * @param offset Desired distance in pixels of <code>position</code> from the top 4631 * of the view when scrolling is finished 4632 * @param duration Number of milliseconds to use for the scroll 4633 */ 4634 public void smoothScrollToPositionFromTop(int position, int offset, int duration) { 4635 if (mPositionScroller == null) { 4636 mPositionScroller = createPositionScroller(); 4637 } 4638 mPositionScroller.startWithOffset(position, offset, duration); 4639 } 4640 4641 /** 4642 * Smoothly scroll to the specified adapter position. The view will scroll 4643 * such that the indicated position is displayed <code>offset</code> pixels below 4644 * the top edge of the view. If this is impossible, (e.g. the offset would scroll 4645 * the first or last item beyond the boundaries of the list) it will get as close 4646 * as possible. 4647 * 4648 * @param position Position to scroll to 4649 * @param offset Desired distance in pixels of <code>position</code> from the top 4650 * of the view when scrolling is finished 4651 */ 4652 public void smoothScrollToPositionFromTop(int position, int offset) { 4653 if (mPositionScroller == null) { 4654 mPositionScroller = createPositionScroller(); 4655 } 4656 mPositionScroller.startWithOffset(position, offset); 4657 } 4658 4659 /** 4660 * Smoothly scroll to the specified adapter position. The view will 4661 * scroll such that the indicated position is displayed, but it will 4662 * stop early if scrolling further would scroll boundPosition out of 4663 * view. 4664 * 4665 * @param position Scroll to this adapter position. 4666 * @param boundPosition Do not scroll if it would move this adapter 4667 * position out of view. 4668 */ 4669 public void smoothScrollToPosition(int position, int boundPosition) { 4670 if (mPositionScroller == null) { 4671 mPositionScroller = createPositionScroller(); 4672 } 4673 mPositionScroller.start(position, boundPosition); 4674 } 4675 4676 /** 4677 * Smoothly scroll by distance pixels over duration milliseconds. 4678 * @param distance Distance to scroll in pixels. 4679 * @param duration Duration of the scroll animation in milliseconds. 4680 */ 4681 public void smoothScrollBy(int distance, int duration) { 4682 smoothScrollBy(distance, duration, false); 4683 } 4684 4685 void smoothScrollBy(int distance, int duration, boolean linear) { 4686 if (mFlingRunnable == null) { 4687 mFlingRunnable = new FlingRunnable(); 4688 } 4689 4690 // No sense starting to scroll if we're not going anywhere 4691 final int firstPos = mFirstPosition; 4692 final int childCount = getChildCount(); 4693 final int lastPos = firstPos + childCount; 4694 final int topLimit = getPaddingTop(); 4695 final int bottomLimit = getHeight() - getPaddingBottom(); 4696 4697 if (distance == 0 || mItemCount == 0 || childCount == 0 || 4698 (firstPos == 0 && getChildAt(0).getTop() == topLimit && distance < 0) || 4699 (lastPos == mItemCount && 4700 getChildAt(childCount - 1).getBottom() == bottomLimit && distance > 0)) { 4701 mFlingRunnable.endFling(); 4702 if (mPositionScroller != null) { 4703 mPositionScroller.stop(); 4704 } 4705 } else { 4706 reportScrollStateChange(OnScrollListener.SCROLL_STATE_FLING); 4707 mFlingRunnable.startScroll(distance, duration, linear); 4708 } 4709 } 4710 4711 /** 4712 * Allows RemoteViews to scroll relatively to a position. 4713 */ 4714 void smoothScrollByOffset(int position) { 4715 int index = -1; 4716 if (position < 0) { 4717 index = getFirstVisiblePosition(); 4718 } else if (position > 0) { 4719 index = getLastVisiblePosition(); 4720 } 4721 4722 if (index > -1) { 4723 View child = getChildAt(index - getFirstVisiblePosition()); 4724 if (child != null) { 4725 Rect visibleRect = new Rect(); 4726 if (child.getGlobalVisibleRect(visibleRect)) { 4727 // the child is partially visible 4728 int childRectArea = child.getWidth() * child.getHeight(); 4729 int visibleRectArea = visibleRect.width() * visibleRect.height(); 4730 float visibleArea = (visibleRectArea / (float) childRectArea); 4731 final float visibleThreshold = 0.75f; 4732 if ((position < 0) && (visibleArea < visibleThreshold)) { 4733 // the top index is not perceivably visible so offset 4734 // to account for showing that top index as well 4735 ++index; 4736 } else if ((position > 0) && (visibleArea < visibleThreshold)) { 4737 // the bottom index is not perceivably visible so offset 4738 // to account for showing that bottom index as well 4739 --index; 4740 } 4741 } 4742 smoothScrollToPosition(Math.max(0, Math.min(getCount(), index + position))); 4743 } 4744 } 4745 } 4746 4747 private void createScrollingCache() { 4748 if (mScrollingCacheEnabled && !mCachingStarted && !isHardwareAccelerated()) { 4749 setChildrenDrawnWithCacheEnabled(true); 4750 setChildrenDrawingCacheEnabled(true); 4751 mCachingStarted = mCachingActive = true; 4752 } 4753 } 4754 4755 private void clearScrollingCache() { 4756 if (!isHardwareAccelerated()) { 4757 if (mClearScrollingCache == null) { 4758 mClearScrollingCache = new Runnable() { 4759 @Override 4760 public void run() { 4761 if (mCachingStarted) { 4762 mCachingStarted = mCachingActive = false; 4763 setChildrenDrawnWithCacheEnabled(false); 4764 if ((mPersistentDrawingCache & PERSISTENT_SCROLLING_CACHE) == 0) { 4765 setChildrenDrawingCacheEnabled(false); 4766 } 4767 if (!isAlwaysDrawnWithCacheEnabled()) { 4768 invalidate(); 4769 } 4770 } 4771 } 4772 }; 4773 } 4774 post(mClearScrollingCache); 4775 } 4776 } 4777 4778 /** 4779 * Scrolls the list items within the view by a specified number of pixels. 4780 * 4781 * @param y the amount of pixels to scroll by vertically 4782 * @see #canScrollList(int) 4783 */ 4784 public void scrollListBy(int y) { 4785 trackMotionScroll(-y, -y); 4786 } 4787 4788 /** 4789 * Check if the items in the list can be scrolled in a certain direction. 4790 * 4791 * @param direction Negative to check scrolling up, positive to check 4792 * scrolling down. 4793 * @return true if the list can be scrolled in the specified direction, 4794 * false otherwise. 4795 * @see #scrollListBy(int) 4796 */ 4797 public boolean canScrollList(int direction) { 4798 final int childCount = getChildCount(); 4799 if (childCount == 0) { 4800 return false; 4801 } 4802 4803 final int firstPosition = mFirstPosition; 4804 final Rect listPadding = mListPadding; 4805 if (direction > 0) { 4806 final int lastBottom = getChildAt(childCount - 1).getBottom(); 4807 final int lastPosition = firstPosition + childCount; 4808 return lastPosition < mItemCount || lastBottom > getHeight() - listPadding.bottom; 4809 } else { 4810 final int firstTop = getChildAt(0).getTop(); 4811 return firstPosition > 0 || firstTop < listPadding.top; 4812 } 4813 } 4814 4815 /** 4816 * Track a motion scroll 4817 * 4818 * @param deltaY Amount to offset mMotionView. This is the accumulated delta since the motion 4819 * began. Positive numbers mean the user's finger is moving down the screen. 4820 * @param incrementalDeltaY Change in deltaY from the previous event. 4821 * @return true if we're already at the beginning/end of the list and have nothing to do. 4822 */ 4823 boolean trackMotionScroll(int deltaY, int incrementalDeltaY) { 4824 final int childCount = getChildCount(); 4825 if (childCount == 0) { 4826 return true; 4827 } 4828 4829 final int firstTop = getChildAt(0).getTop(); 4830 final int lastBottom = getChildAt(childCount - 1).getBottom(); 4831 4832 final Rect listPadding = mListPadding; 4833 4834 // "effective padding" In this case is the amount of padding that affects 4835 // how much space should not be filled by items. If we don't clip to padding 4836 // there is no effective padding. 4837 int effectivePaddingTop = 0; 4838 int effectivePaddingBottom = 0; 4839 if ((mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK) { 4840 effectivePaddingTop = listPadding.top; 4841 effectivePaddingBottom = listPadding.bottom; 4842 } 4843 4844 // FIXME account for grid vertical spacing too? 4845 final int spaceAbove = effectivePaddingTop - firstTop; 4846 final int end = getHeight() - effectivePaddingBottom; 4847 final int spaceBelow = lastBottom - end; 4848 4849 final int height = getHeight() - mPaddingBottom - mPaddingTop; 4850 if (deltaY < 0) { 4851 deltaY = Math.max(-(height - 1), deltaY); 4852 } else { 4853 deltaY = Math.min(height - 1, deltaY); 4854 } 4855 4856 if (incrementalDeltaY < 0) { 4857 incrementalDeltaY = Math.max(-(height - 1), incrementalDeltaY); 4858 } else { 4859 incrementalDeltaY = Math.min(height - 1, incrementalDeltaY); 4860 } 4861 4862 final int firstPosition = mFirstPosition; 4863 4864 // Update our guesses for where the first and last views are 4865 if (firstPosition == 0) { 4866 mFirstPositionDistanceGuess = firstTop - listPadding.top; 4867 } else { 4868 mFirstPositionDistanceGuess += incrementalDeltaY; 4869 } 4870 if (firstPosition + childCount == mItemCount) { 4871 mLastPositionDistanceGuess = lastBottom + listPadding.bottom; 4872 } else { 4873 mLastPositionDistanceGuess += incrementalDeltaY; 4874 } 4875 4876 final boolean cannotScrollDown = (firstPosition == 0 && 4877 firstTop >= listPadding.top && incrementalDeltaY >= 0); 4878 final boolean cannotScrollUp = (firstPosition + childCount == mItemCount && 4879 lastBottom <= getHeight() - listPadding.bottom && incrementalDeltaY <= 0); 4880 4881 if (cannotScrollDown || cannotScrollUp) { 4882 return incrementalDeltaY != 0; 4883 } 4884 4885 final boolean down = incrementalDeltaY < 0; 4886 4887 final boolean inTouchMode = isInTouchMode(); 4888 if (inTouchMode) { 4889 hideSelector(); 4890 } 4891 4892 final int headerViewsCount = getHeaderViewsCount(); 4893 final int footerViewsStart = mItemCount - getFooterViewsCount(); 4894 4895 int start = 0; 4896 int count = 0; 4897 4898 if (down) { 4899 int top = -incrementalDeltaY; 4900 if ((mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK) { 4901 top += listPadding.top; 4902 } 4903 for (int i = 0; i < childCount; i++) { 4904 final View child = getChildAt(i); 4905 if (child.getBottom() >= top) { 4906 break; 4907 } else { 4908 count++; 4909 int position = firstPosition + i; 4910 if (position >= headerViewsCount && position < footerViewsStart) { 4911 // The view will be rebound to new data, clear any 4912 // system-managed transient state. 4913 child.clearAccessibilityFocus(); 4914 mRecycler.addScrapView(child, position); 4915 } 4916 } 4917 } 4918 } else { 4919 int bottom = getHeight() - incrementalDeltaY; 4920 if ((mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK) { 4921 bottom -= listPadding.bottom; 4922 } 4923 for (int i = childCount - 1; i >= 0; i--) { 4924 final View child = getChildAt(i); 4925 if (child.getTop() <= bottom) { 4926 break; 4927 } else { 4928 start = i; 4929 count++; 4930 int position = firstPosition + i; 4931 if (position >= headerViewsCount && position < footerViewsStart) { 4932 // The view will be rebound to new data, clear any 4933 // system-managed transient state. 4934 child.clearAccessibilityFocus(); 4935 mRecycler.addScrapView(child, position); 4936 } 4937 } 4938 } 4939 } 4940 4941 mMotionViewNewTop = mMotionViewOriginalTop + deltaY; 4942 4943 mBlockLayoutRequests = true; 4944 4945 if (count > 0) { 4946 detachViewsFromParent(start, count); 4947 mRecycler.removeSkippedScrap(); 4948 } 4949 4950 // invalidate before moving the children to avoid unnecessary invalidate 4951 // calls to bubble up from the children all the way to the top 4952 if (!awakenScrollBars()) { 4953 invalidate(); 4954 } 4955 4956 offsetChildrenTopAndBottom(incrementalDeltaY); 4957 4958 if (down) { 4959 mFirstPosition += count; 4960 } 4961 4962 final int absIncrementalDeltaY = Math.abs(incrementalDeltaY); 4963 if (spaceAbove < absIncrementalDeltaY || spaceBelow < absIncrementalDeltaY) { 4964 fillGap(down); 4965 } 4966 4967 if (!inTouchMode && mSelectedPosition != INVALID_POSITION) { 4968 final int childIndex = mSelectedPosition - mFirstPosition; 4969 if (childIndex >= 0 && childIndex < getChildCount()) { 4970 positionSelector(mSelectedPosition, getChildAt(childIndex)); 4971 } 4972 } else if (mSelectorPosition != INVALID_POSITION) { 4973 final int childIndex = mSelectorPosition - mFirstPosition; 4974 if (childIndex >= 0 && childIndex < getChildCount()) { 4975 positionSelector(INVALID_POSITION, getChildAt(childIndex)); 4976 } 4977 } else { 4978 mSelectorRect.setEmpty(); 4979 } 4980 4981 mBlockLayoutRequests = false; 4982 4983 invokeOnItemScrollListener(); 4984 4985 return false; 4986 } 4987 4988 /** 4989 * Returns the number of header views in the list. Header views are special views 4990 * at the top of the list that should not be recycled during a layout. 4991 * 4992 * @return The number of header views, 0 in the default implementation. 4993 */ 4994 int getHeaderViewsCount() { 4995 return 0; 4996 } 4997 4998 /** 4999 * Returns the number of footer views in the list. Footer views are special views 5000 * at the bottom of the list that should not be recycled during a layout. 5001 * 5002 * @return The number of footer views, 0 in the default implementation. 5003 */ 5004 int getFooterViewsCount() { 5005 return 0; 5006 } 5007 5008 /** 5009 * Fills the gap left open by a touch-scroll. During a touch scroll, children that 5010 * remain on screen are shifted and the other ones are discarded. The role of this 5011 * method is to fill the gap thus created by performing a partial layout in the 5012 * empty space. 5013 * 5014 * @param down true if the scroll is going down, false if it is going up 5015 */ 5016 abstract void fillGap(boolean down); 5017 5018 void hideSelector() { 5019 if (mSelectedPosition != INVALID_POSITION) { 5020 if (mLayoutMode != LAYOUT_SPECIFIC) { 5021 mResurrectToPosition = mSelectedPosition; 5022 } 5023 if (mNextSelectedPosition >= 0 && mNextSelectedPosition != mSelectedPosition) { 5024 mResurrectToPosition = mNextSelectedPosition; 5025 } 5026 setSelectedPositionInt(INVALID_POSITION); 5027 setNextSelectedPositionInt(INVALID_POSITION); 5028 mSelectedTop = 0; 5029 } 5030 } 5031 5032 /** 5033 * @return A position to select. First we try mSelectedPosition. If that has been clobbered by 5034 * entering touch mode, we then try mResurrectToPosition. Values are pinned to the range 5035 * of items available in the adapter 5036 */ 5037 int reconcileSelectedPosition() { 5038 int position = mSelectedPosition; 5039 if (position < 0) { 5040 position = mResurrectToPosition; 5041 } 5042 position = Math.max(0, position); 5043 position = Math.min(position, mItemCount - 1); 5044 return position; 5045 } 5046 5047 /** 5048 * Find the row closest to y. This row will be used as the motion row when scrolling 5049 * 5050 * @param y Where the user touched 5051 * @return The position of the first (or only) item in the row containing y 5052 */ 5053 abstract int findMotionRow(int y); 5054 5055 /** 5056 * Find the row closest to y. This row will be used as the motion row when scrolling. 5057 * 5058 * @param y Where the user touched 5059 * @return The position of the first (or only) item in the row closest to y 5060 */ 5061 int findClosestMotionRow(int y) { 5062 final int childCount = getChildCount(); 5063 if (childCount == 0) { 5064 return INVALID_POSITION; 5065 } 5066 5067 final int motionRow = findMotionRow(y); 5068 return motionRow != INVALID_POSITION ? motionRow : mFirstPosition + childCount - 1; 5069 } 5070 5071 /** 5072 * Causes all the views to be rebuilt and redrawn. 5073 */ 5074 public void invalidateViews() { 5075 mDataChanged = true; 5076 rememberSyncState(); 5077 requestLayout(); 5078 invalidate(); 5079 } 5080 5081 /** 5082 * If there is a selection returns false. 5083 * Otherwise resurrects the selection and returns true if resurrected. 5084 */ 5085 boolean resurrectSelectionIfNeeded() { 5086 if (mSelectedPosition < 0 && resurrectSelection()) { 5087 updateSelectorState(); 5088 return true; 5089 } 5090 return false; 5091 } 5092 5093 /** 5094 * Makes the item at the supplied position selected. 5095 * 5096 * @param position the position of the new selection 5097 */ 5098 abstract void setSelectionInt(int position); 5099 5100 /** 5101 * Attempt to bring the selection back if the user is switching from touch 5102 * to trackball mode 5103 * @return Whether selection was set to something. 5104 */ 5105 boolean resurrectSelection() { 5106 final int childCount = getChildCount(); 5107 5108 if (childCount <= 0) { 5109 return false; 5110 } 5111 5112 int selectedTop = 0; 5113 int selectedPos; 5114 int childrenTop = mListPadding.top; 5115 int childrenBottom = mBottom - mTop - mListPadding.bottom; 5116 final int firstPosition = mFirstPosition; 5117 final int toPosition = mResurrectToPosition; 5118 boolean down = true; 5119 5120 if (toPosition >= firstPosition && toPosition < firstPosition + childCount) { 5121 selectedPos = toPosition; 5122 5123 final View selected = getChildAt(selectedPos - mFirstPosition); 5124 selectedTop = selected.getTop(); 5125 int selectedBottom = selected.getBottom(); 5126 5127 // We are scrolled, don't get in the fade 5128 if (selectedTop < childrenTop) { 5129 selectedTop = childrenTop + getVerticalFadingEdgeLength(); 5130 } else if (selectedBottom > childrenBottom) { 5131 selectedTop = childrenBottom - selected.getMeasuredHeight() 5132 - getVerticalFadingEdgeLength(); 5133 } 5134 } else { 5135 if (toPosition < firstPosition) { 5136 // Default to selecting whatever is first 5137 selectedPos = firstPosition; 5138 for (int i = 0; i < childCount; i++) { 5139 final View v = getChildAt(i); 5140 final int top = v.getTop(); 5141 5142 if (i == 0) { 5143 // Remember the position of the first item 5144 selectedTop = top; 5145 // See if we are scrolled at all 5146 if (firstPosition > 0 || top < childrenTop) { 5147 // If we are scrolled, don't select anything that is 5148 // in the fade region 5149 childrenTop += getVerticalFadingEdgeLength(); 5150 } 5151 } 5152 if (top >= childrenTop) { 5153 // Found a view whose top is fully visisble 5154 selectedPos = firstPosition + i; 5155 selectedTop = top; 5156 break; 5157 } 5158 } 5159 } else { 5160 final int itemCount = mItemCount; 5161 down = false; 5162 selectedPos = firstPosition + childCount - 1; 5163 5164 for (int i = childCount - 1; i >= 0; i--) { 5165 final View v = getChildAt(i); 5166 final int top = v.getTop(); 5167 final int bottom = v.getBottom(); 5168 5169 if (i == childCount - 1) { 5170 selectedTop = top; 5171 if (firstPosition + childCount < itemCount || bottom > childrenBottom) { 5172 childrenBottom -= getVerticalFadingEdgeLength(); 5173 } 5174 } 5175 5176 if (bottom <= childrenBottom) { 5177 selectedPos = firstPosition + i; 5178 selectedTop = top; 5179 break; 5180 } 5181 } 5182 } 5183 } 5184 5185 mResurrectToPosition = INVALID_POSITION; 5186 removeCallbacks(mFlingRunnable); 5187 if (mPositionScroller != null) { 5188 mPositionScroller.stop(); 5189 } 5190 mTouchMode = TOUCH_MODE_REST; 5191 clearScrollingCache(); 5192 mSpecificTop = selectedTop; 5193 selectedPos = lookForSelectablePosition(selectedPos, down); 5194 if (selectedPos >= firstPosition && selectedPos <= getLastVisiblePosition()) { 5195 mLayoutMode = LAYOUT_SPECIFIC; 5196 updateSelectorState(); 5197 setSelectionInt(selectedPos); 5198 invokeOnItemScrollListener(); 5199 } else { 5200 selectedPos = INVALID_POSITION; 5201 } 5202 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 5203 5204 return selectedPos >= 0; 5205 } 5206 5207 void confirmCheckedPositionsById() { 5208 // Clear out the positional check states, we'll rebuild it below from IDs. 5209 mCheckStates.clear(); 5210 5211 boolean checkedCountChanged = false; 5212 for (int checkedIndex = 0; checkedIndex < mCheckedIdStates.size(); checkedIndex++) { 5213 final long id = mCheckedIdStates.keyAt(checkedIndex); 5214 final int lastPos = mCheckedIdStates.valueAt(checkedIndex); 5215 5216 final long lastPosId = mAdapter.getItemId(lastPos); 5217 if (id != lastPosId) { 5218 // Look around to see if the ID is nearby. If not, uncheck it. 5219 final int start = Math.max(0, lastPos - CHECK_POSITION_SEARCH_DISTANCE); 5220 final int end = Math.min(lastPos + CHECK_POSITION_SEARCH_DISTANCE, mItemCount); 5221 boolean found = false; 5222 for (int searchPos = start; searchPos < end; searchPos++) { 5223 final long searchId = mAdapter.getItemId(searchPos); 5224 if (id == searchId) { 5225 found = true; 5226 mCheckStates.put(searchPos, true); 5227 mCheckedIdStates.setValueAt(checkedIndex, searchPos); 5228 break; 5229 } 5230 } 5231 5232 if (!found) { 5233 mCheckedIdStates.delete(id); 5234 checkedIndex--; 5235 mCheckedItemCount--; 5236 checkedCountChanged = true; 5237 if (mChoiceActionMode != null && mMultiChoiceModeCallback != null) { 5238 mMultiChoiceModeCallback.onItemCheckedStateChanged(mChoiceActionMode, 5239 lastPos, id, false); 5240 } 5241 } 5242 } else { 5243 mCheckStates.put(lastPos, true); 5244 } 5245 } 5246 5247 if (checkedCountChanged && mChoiceActionMode != null) { 5248 mChoiceActionMode.invalidate(); 5249 } 5250 } 5251 5252 @Override 5253 protected void handleDataChanged() { 5254 int count = mItemCount; 5255 int lastHandledItemCount = mLastHandledItemCount; 5256 mLastHandledItemCount = mItemCount; 5257 5258 if (mChoiceMode != CHOICE_MODE_NONE && mAdapter != null && mAdapter.hasStableIds()) { 5259 confirmCheckedPositionsById(); 5260 } 5261 5262 // TODO: In the future we can recycle these views based on stable ID instead. 5263 mRecycler.clearTransientStateViews(); 5264 5265 if (count > 0) { 5266 int newPos; 5267 int selectablePos; 5268 5269 // Find the row we are supposed to sync to 5270 if (mNeedSync) { 5271 // Update this first, since setNextSelectedPositionInt inspects it 5272 mNeedSync = false; 5273 mPendingSync = null; 5274 5275 if (mTranscriptMode == TRANSCRIPT_MODE_ALWAYS_SCROLL) { 5276 mLayoutMode = LAYOUT_FORCE_BOTTOM; 5277 return; 5278 } else if (mTranscriptMode == TRANSCRIPT_MODE_NORMAL) { 5279 if (mForceTranscriptScroll) { 5280 mForceTranscriptScroll = false; 5281 mLayoutMode = LAYOUT_FORCE_BOTTOM; 5282 return; 5283 } 5284 final int childCount = getChildCount(); 5285 final int listBottom = getHeight() - getPaddingBottom(); 5286 final View lastChild = getChildAt(childCount - 1); 5287 final int lastBottom = lastChild != null ? lastChild.getBottom() : listBottom; 5288 if (mFirstPosition + childCount >= lastHandledItemCount && 5289 lastBottom <= listBottom) { 5290 mLayoutMode = LAYOUT_FORCE_BOTTOM; 5291 return; 5292 } 5293 // Something new came in and we didn't scroll; give the user a clue that 5294 // there's something new. 5295 awakenScrollBars(); 5296 } 5297 5298 switch (mSyncMode) { 5299 case SYNC_SELECTED_POSITION: 5300 if (isInTouchMode()) { 5301 // We saved our state when not in touch mode. (We know this because 5302 // mSyncMode is SYNC_SELECTED_POSITION.) Now we are trying to 5303 // restore in touch mode. Just leave mSyncPosition as it is (possibly 5304 // adjusting if the available range changed) and return. 5305 mLayoutMode = LAYOUT_SYNC; 5306 mSyncPosition = Math.min(Math.max(0, mSyncPosition), count - 1); 5307 5308 return; 5309 } else { 5310 // See if we can find a position in the new data with the same 5311 // id as the old selection. This will change mSyncPosition. 5312 newPos = findSyncPosition(); 5313 if (newPos >= 0) { 5314 // Found it. Now verify that new selection is still selectable 5315 selectablePos = lookForSelectablePosition(newPos, true); 5316 if (selectablePos == newPos) { 5317 // Same row id is selected 5318 mSyncPosition = newPos; 5319 5320 if (mSyncHeight == getHeight()) { 5321 // If we are at the same height as when we saved state, try 5322 // to restore the scroll position too. 5323 mLayoutMode = LAYOUT_SYNC; 5324 } else { 5325 // We are not the same height as when the selection was saved, so 5326 // don't try to restore the exact position 5327 mLayoutMode = LAYOUT_SET_SELECTION; 5328 } 5329 5330 // Restore selection 5331 setNextSelectedPositionInt(newPos); 5332 return; 5333 } 5334 } 5335 } 5336 break; 5337 case SYNC_FIRST_POSITION: 5338 // Leave mSyncPosition as it is -- just pin to available range 5339 mLayoutMode = LAYOUT_SYNC; 5340 mSyncPosition = Math.min(Math.max(0, mSyncPosition), count - 1); 5341 5342 return; 5343 } 5344 } 5345 5346 if (!isInTouchMode()) { 5347 // We couldn't find matching data -- try to use the same position 5348 newPos = getSelectedItemPosition(); 5349 5350 // Pin position to the available range 5351 if (newPos >= count) { 5352 newPos = count - 1; 5353 } 5354 if (newPos < 0) { 5355 newPos = 0; 5356 } 5357 5358 // Make sure we select something selectable -- first look down 5359 selectablePos = lookForSelectablePosition(newPos, true); 5360 5361 if (selectablePos >= 0) { 5362 setNextSelectedPositionInt(selectablePos); 5363 return; 5364 } else { 5365 // Looking down didn't work -- try looking up 5366 selectablePos = lookForSelectablePosition(newPos, false); 5367 if (selectablePos >= 0) { 5368 setNextSelectedPositionInt(selectablePos); 5369 return; 5370 } 5371 } 5372 } else { 5373 5374 // We already know where we want to resurrect the selection 5375 if (mResurrectToPosition >= 0) { 5376 return; 5377 } 5378 } 5379 5380 } 5381 5382 // Nothing is selected. Give up and reset everything. 5383 mLayoutMode = mStackFromBottom ? LAYOUT_FORCE_BOTTOM : LAYOUT_FORCE_TOP; 5384 mSelectedPosition = INVALID_POSITION; 5385 mSelectedRowId = INVALID_ROW_ID; 5386 mNextSelectedPosition = INVALID_POSITION; 5387 mNextSelectedRowId = INVALID_ROW_ID; 5388 mNeedSync = false; 5389 mPendingSync = null; 5390 mSelectorPosition = INVALID_POSITION; 5391 checkSelectionChanged(); 5392 } 5393 5394 @Override 5395 protected void onDisplayHint(int hint) { 5396 super.onDisplayHint(hint); 5397 switch (hint) { 5398 case INVISIBLE: 5399 if (mPopup != null && mPopup.isShowing()) { 5400 dismissPopup(); 5401 } 5402 break; 5403 case VISIBLE: 5404 if (mFiltered && mPopup != null && !mPopup.isShowing()) { 5405 showPopup(); 5406 } 5407 break; 5408 } 5409 mPopupHidden = hint == INVISIBLE; 5410 } 5411 5412 /** 5413 * Removes the filter window 5414 */ 5415 private void dismissPopup() { 5416 if (mPopup != null) { 5417 mPopup.dismiss(); 5418 } 5419 } 5420 5421 /** 5422 * Shows the filter window 5423 */ 5424 private void showPopup() { 5425 // Make sure we have a window before showing the popup 5426 if (getWindowVisibility() == View.VISIBLE) { 5427 createTextFilter(true); 5428 positionPopup(); 5429 // Make sure we get focus if we are showing the popup 5430 checkFocus(); 5431 } 5432 } 5433 5434 private void positionPopup() { 5435 int screenHeight = getResources().getDisplayMetrics().heightPixels; 5436 final int[] xy = new int[2]; 5437 getLocationOnScreen(xy); 5438 // TODO: The 20 below should come from the theme 5439 // TODO: And the gravity should be defined in the theme as well 5440 final int bottomGap = screenHeight - xy[1] - getHeight() + (int) (mDensityScale * 20); 5441 if (!mPopup.isShowing()) { 5442 mPopup.showAtLocation(this, Gravity.BOTTOM | Gravity.CENTER_HORIZONTAL, 5443 xy[0], bottomGap); 5444 } else { 5445 mPopup.update(xy[0], bottomGap, -1, -1); 5446 } 5447 } 5448 5449 /** 5450 * What is the distance between the source and destination rectangles given the direction of 5451 * focus navigation between them? The direction basically helps figure out more quickly what is 5452 * self evident by the relationship between the rects... 5453 * 5454 * @param source the source rectangle 5455 * @param dest the destination rectangle 5456 * @param direction the direction 5457 * @return the distance between the rectangles 5458 */ 5459 static int getDistance(Rect source, Rect dest, int direction) { 5460 int sX, sY; // source x, y 5461 int dX, dY; // dest x, y 5462 switch (direction) { 5463 case View.FOCUS_RIGHT: 5464 sX = source.right; 5465 sY = source.top + source.height() / 2; 5466 dX = dest.left; 5467 dY = dest.top + dest.height() / 2; 5468 break; 5469 case View.FOCUS_DOWN: 5470 sX = source.left + source.width() / 2; 5471 sY = source.bottom; 5472 dX = dest.left + dest.width() / 2; 5473 dY = dest.top; 5474 break; 5475 case View.FOCUS_LEFT: 5476 sX = source.left; 5477 sY = source.top + source.height() / 2; 5478 dX = dest.right; 5479 dY = dest.top + dest.height() / 2; 5480 break; 5481 case View.FOCUS_UP: 5482 sX = source.left + source.width() / 2; 5483 sY = source.top; 5484 dX = dest.left + dest.width() / 2; 5485 dY = dest.bottom; 5486 break; 5487 case View.FOCUS_FORWARD: 5488 case View.FOCUS_BACKWARD: 5489 sX = source.right + source.width() / 2; 5490 sY = source.top + source.height() / 2; 5491 dX = dest.left + dest.width() / 2; 5492 dY = dest.top + dest.height() / 2; 5493 break; 5494 default: 5495 throw new IllegalArgumentException("direction must be one of " 5496 + "{FOCUS_UP, FOCUS_DOWN, FOCUS_LEFT, FOCUS_RIGHT, " 5497 + "FOCUS_FORWARD, FOCUS_BACKWARD}."); 5498 } 5499 int deltaX = dX - sX; 5500 int deltaY = dY - sY; 5501 return deltaY * deltaY + deltaX * deltaX; 5502 } 5503 5504 @Override 5505 protected boolean isInFilterMode() { 5506 return mFiltered; 5507 } 5508 5509 /** 5510 * Sends a key to the text filter window 5511 * 5512 * @param keyCode The keycode for the event 5513 * @param event The actual key event 5514 * 5515 * @return True if the text filter handled the event, false otherwise. 5516 */ 5517 boolean sendToTextFilter(int keyCode, int count, KeyEvent event) { 5518 if (!acceptFilter()) { 5519 return false; 5520 } 5521 5522 boolean handled = false; 5523 boolean okToSend = true; 5524 switch (keyCode) { 5525 case KeyEvent.KEYCODE_DPAD_UP: 5526 case KeyEvent.KEYCODE_DPAD_DOWN: 5527 case KeyEvent.KEYCODE_DPAD_LEFT: 5528 case KeyEvent.KEYCODE_DPAD_RIGHT: 5529 case KeyEvent.KEYCODE_DPAD_CENTER: 5530 case KeyEvent.KEYCODE_ENTER: 5531 okToSend = false; 5532 break; 5533 case KeyEvent.KEYCODE_BACK: 5534 if (mFiltered && mPopup != null && mPopup.isShowing()) { 5535 if (event.getAction() == KeyEvent.ACTION_DOWN 5536 && event.getRepeatCount() == 0) { 5537 KeyEvent.DispatcherState state = getKeyDispatcherState(); 5538 if (state != null) { 5539 state.startTracking(event, this); 5540 } 5541 handled = true; 5542 } else if (event.getAction() == KeyEvent.ACTION_UP 5543 && event.isTracking() && !event.isCanceled()) { 5544 handled = true; 5545 mTextFilter.setText(""); 5546 } 5547 } 5548 okToSend = false; 5549 break; 5550 case KeyEvent.KEYCODE_SPACE: 5551 // Only send spaces once we are filtered 5552 okToSend = mFiltered; 5553 break; 5554 } 5555 5556 if (okToSend) { 5557 createTextFilter(true); 5558 5559 KeyEvent forwardEvent = event; 5560 if (forwardEvent.getRepeatCount() > 0) { 5561 forwardEvent = KeyEvent.changeTimeRepeat(event, event.getEventTime(), 0); 5562 } 5563 5564 int action = event.getAction(); 5565 switch (action) { 5566 case KeyEvent.ACTION_DOWN: 5567 handled = mTextFilter.onKeyDown(keyCode, forwardEvent); 5568 break; 5569 5570 case KeyEvent.ACTION_UP: 5571 handled = mTextFilter.onKeyUp(keyCode, forwardEvent); 5572 break; 5573 5574 case KeyEvent.ACTION_MULTIPLE: 5575 handled = mTextFilter.onKeyMultiple(keyCode, count, event); 5576 break; 5577 } 5578 } 5579 return handled; 5580 } 5581 5582 /** 5583 * Return an InputConnection for editing of the filter text. 5584 */ 5585 @Override 5586 public InputConnection onCreateInputConnection(EditorInfo outAttrs) { 5587 if (isTextFilterEnabled()) { 5588 if (mPublicInputConnection == null) { 5589 mDefInputConnection = new BaseInputConnection(this, false); 5590 mPublicInputConnection = new InputConnectionWrapper(outAttrs); 5591 } 5592 outAttrs.inputType = EditorInfo.TYPE_CLASS_TEXT | EditorInfo.TYPE_TEXT_VARIATION_FILTER; 5593 outAttrs.imeOptions = EditorInfo.IME_ACTION_DONE; 5594 return mPublicInputConnection; 5595 } 5596 return null; 5597 } 5598 5599 private class InputConnectionWrapper implements InputConnection { 5600 private final EditorInfo mOutAttrs; 5601 private InputConnection mTarget; 5602 5603 public InputConnectionWrapper(EditorInfo outAttrs) { 5604 mOutAttrs = outAttrs; 5605 } 5606 5607 private InputConnection getTarget() { 5608 if (mTarget == null) { 5609 mTarget = getTextFilterInput().onCreateInputConnection(mOutAttrs); 5610 } 5611 return mTarget; 5612 } 5613 5614 @Override 5615 public boolean reportFullscreenMode(boolean enabled) { 5616 // Use our own input connection, since it is 5617 // the "real" one the IME is talking with. 5618 return mDefInputConnection.reportFullscreenMode(enabled); 5619 } 5620 5621 @Override 5622 public boolean performEditorAction(int editorAction) { 5623 // The editor is off in its own window; we need to be 5624 // the one that does this. 5625 if (editorAction == EditorInfo.IME_ACTION_DONE) { 5626 InputMethodManager imm = (InputMethodManager) 5627 getContext().getSystemService(Context.INPUT_METHOD_SERVICE); 5628 if (imm != null) { 5629 imm.hideSoftInputFromWindow(getWindowToken(), 0); 5630 } 5631 return true; 5632 } 5633 return false; 5634 } 5635 5636 @Override 5637 public boolean sendKeyEvent(KeyEvent event) { 5638 // Use our own input connection, since the filter 5639 // text view may not be shown in a window so has 5640 // no ViewAncestor to dispatch events with. 5641 return mDefInputConnection.sendKeyEvent(event); 5642 } 5643 5644 @Override 5645 public CharSequence getTextBeforeCursor(int n, int flags) { 5646 if (mTarget == null) return ""; 5647 return mTarget.getTextBeforeCursor(n, flags); 5648 } 5649 5650 @Override 5651 public CharSequence getTextAfterCursor(int n, int flags) { 5652 if (mTarget == null) return ""; 5653 return mTarget.getTextAfterCursor(n, flags); 5654 } 5655 5656 @Override 5657 public CharSequence getSelectedText(int flags) { 5658 if (mTarget == null) return ""; 5659 return mTarget.getSelectedText(flags); 5660 } 5661 5662 @Override 5663 public int getCursorCapsMode(int reqModes) { 5664 if (mTarget == null) return InputType.TYPE_TEXT_FLAG_CAP_SENTENCES; 5665 return mTarget.getCursorCapsMode(reqModes); 5666 } 5667 5668 @Override 5669 public ExtractedText getExtractedText(ExtractedTextRequest request, int flags) { 5670 return getTarget().getExtractedText(request, flags); 5671 } 5672 5673 @Override 5674 public boolean deleteSurroundingText(int beforeLength, int afterLength) { 5675 return getTarget().deleteSurroundingText(beforeLength, afterLength); 5676 } 5677 5678 @Override 5679 public boolean setComposingText(CharSequence text, int newCursorPosition) { 5680 return getTarget().setComposingText(text, newCursorPosition); 5681 } 5682 5683 @Override 5684 public boolean setComposingRegion(int start, int end) { 5685 return getTarget().setComposingRegion(start, end); 5686 } 5687 5688 @Override 5689 public boolean finishComposingText() { 5690 return mTarget == null || mTarget.finishComposingText(); 5691 } 5692 5693 @Override 5694 public boolean commitText(CharSequence text, int newCursorPosition) { 5695 return getTarget().commitText(text, newCursorPosition); 5696 } 5697 5698 @Override 5699 public boolean commitCompletion(CompletionInfo text) { 5700 return getTarget().commitCompletion(text); 5701 } 5702 5703 @Override 5704 public boolean commitCorrection(CorrectionInfo correctionInfo) { 5705 return getTarget().commitCorrection(correctionInfo); 5706 } 5707 5708 @Override 5709 public boolean setSelection(int start, int end) { 5710 return getTarget().setSelection(start, end); 5711 } 5712 5713 @Override 5714 public boolean performContextMenuAction(int id) { 5715 return getTarget().performContextMenuAction(id); 5716 } 5717 5718 @Override 5719 public boolean beginBatchEdit() { 5720 return getTarget().beginBatchEdit(); 5721 } 5722 5723 @Override 5724 public boolean endBatchEdit() { 5725 return getTarget().endBatchEdit(); 5726 } 5727 5728 @Override 5729 public boolean clearMetaKeyStates(int states) { 5730 return getTarget().clearMetaKeyStates(states); 5731 } 5732 5733 @Override 5734 public boolean performPrivateCommand(String action, Bundle data) { 5735 return getTarget().performPrivateCommand(action, data); 5736 } 5737 5738 @Override 5739 public boolean requestCursorUpdates(int cursorUpdateMode) { 5740 return getTarget().requestCursorUpdates(cursorUpdateMode); 5741 } 5742 } 5743 5744 /** 5745 * For filtering we proxy an input connection to an internal text editor, 5746 * and this allows the proxying to happen. 5747 */ 5748 @Override 5749 public boolean checkInputConnectionProxy(View view) { 5750 return view == mTextFilter; 5751 } 5752 5753 /** 5754 * Creates the window for the text filter and populates it with an EditText field; 5755 * 5756 * @param animateEntrance true if the window should appear with an animation 5757 */ 5758 private void createTextFilter(boolean animateEntrance) { 5759 if (mPopup == null) { 5760 PopupWindow p = new PopupWindow(getContext()); 5761 p.setFocusable(false); 5762 p.setTouchable(false); 5763 p.setInputMethodMode(PopupWindow.INPUT_METHOD_NOT_NEEDED); 5764 p.setContentView(getTextFilterInput()); 5765 p.setWidth(LayoutParams.WRAP_CONTENT); 5766 p.setHeight(LayoutParams.WRAP_CONTENT); 5767 p.setBackgroundDrawable(null); 5768 mPopup = p; 5769 getViewTreeObserver().addOnGlobalLayoutListener(this); 5770 mGlobalLayoutListenerAddedFilter = true; 5771 } 5772 if (animateEntrance) { 5773 mPopup.setAnimationStyle(com.android.internal.R.style.Animation_TypingFilter); 5774 } else { 5775 mPopup.setAnimationStyle(com.android.internal.R.style.Animation_TypingFilterRestore); 5776 } 5777 } 5778 5779 private EditText getTextFilterInput() { 5780 if (mTextFilter == null) { 5781 final LayoutInflater layoutInflater = LayoutInflater.from(getContext()); 5782 mTextFilter = (EditText) layoutInflater.inflate( 5783 com.android.internal.R.layout.typing_filter, null); 5784 // For some reason setting this as the "real" input type changes 5785 // the text view in some way that it doesn't work, and I don't 5786 // want to figure out why this is. 5787 mTextFilter.setRawInputType(EditorInfo.TYPE_CLASS_TEXT 5788 | EditorInfo.TYPE_TEXT_VARIATION_FILTER); 5789 mTextFilter.setImeOptions(EditorInfo.IME_FLAG_NO_EXTRACT_UI); 5790 mTextFilter.addTextChangedListener(this); 5791 } 5792 return mTextFilter; 5793 } 5794 5795 /** 5796 * Clear the text filter. 5797 */ 5798 public void clearTextFilter() { 5799 if (mFiltered) { 5800 getTextFilterInput().setText(""); 5801 mFiltered = false; 5802 if (mPopup != null && mPopup.isShowing()) { 5803 dismissPopup(); 5804 } 5805 } 5806 } 5807 5808 /** 5809 * Returns if the ListView currently has a text filter. 5810 */ 5811 public boolean hasTextFilter() { 5812 return mFiltered; 5813 } 5814 5815 @Override 5816 public void onGlobalLayout() { 5817 if (isShown()) { 5818 // Show the popup if we are filtered 5819 if (mFiltered && mPopup != null && !mPopup.isShowing() && !mPopupHidden) { 5820 showPopup(); 5821 } 5822 } else { 5823 // Hide the popup when we are no longer visible 5824 if (mPopup != null && mPopup.isShowing()) { 5825 dismissPopup(); 5826 } 5827 } 5828 5829 } 5830 5831 /** 5832 * For our text watcher that is associated with the text filter. Does 5833 * nothing. 5834 */ 5835 @Override 5836 public void beforeTextChanged(CharSequence s, int start, int count, int after) { 5837 } 5838 5839 /** 5840 * For our text watcher that is associated with the text filter. Performs 5841 * the actual filtering as the text changes, and takes care of hiding and 5842 * showing the popup displaying the currently entered filter text. 5843 */ 5844 @Override 5845 public void onTextChanged(CharSequence s, int start, int before, int count) { 5846 if (isTextFilterEnabled()) { 5847 createTextFilter(true); 5848 int length = s.length(); 5849 boolean showing = mPopup.isShowing(); 5850 if (!showing && length > 0) { 5851 // Show the filter popup if necessary 5852 showPopup(); 5853 mFiltered = true; 5854 } else if (showing && length == 0) { 5855 // Remove the filter popup if the user has cleared all text 5856 dismissPopup(); 5857 mFiltered = false; 5858 } 5859 if (mAdapter instanceof Filterable) { 5860 Filter f = ((Filterable) mAdapter).getFilter(); 5861 // Filter should not be null when we reach this part 5862 if (f != null) { 5863 f.filter(s, this); 5864 } else { 5865 throw new IllegalStateException("You cannot call onTextChanged with a non " 5866 + "filterable adapter"); 5867 } 5868 } 5869 } 5870 } 5871 5872 /** 5873 * For our text watcher that is associated with the text filter. Does 5874 * nothing. 5875 */ 5876 @Override 5877 public void afterTextChanged(Editable s) { 5878 } 5879 5880 @Override 5881 public void onFilterComplete(int count) { 5882 if (mSelectedPosition < 0 && count > 0) { 5883 mResurrectToPosition = INVALID_POSITION; 5884 resurrectSelection(); 5885 } 5886 } 5887 5888 @Override 5889 protected ViewGroup.LayoutParams generateDefaultLayoutParams() { 5890 return new AbsListView.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, 5891 ViewGroup.LayoutParams.WRAP_CONTENT, 0); 5892 } 5893 5894 @Override 5895 protected ViewGroup.LayoutParams generateLayoutParams(ViewGroup.LayoutParams p) { 5896 return new LayoutParams(p); 5897 } 5898 5899 @Override 5900 public LayoutParams generateLayoutParams(AttributeSet attrs) { 5901 return new AbsListView.LayoutParams(getContext(), attrs); 5902 } 5903 5904 @Override 5905 protected boolean checkLayoutParams(ViewGroup.LayoutParams p) { 5906 return p instanceof AbsListView.LayoutParams; 5907 } 5908 5909 /** 5910 * Puts the list or grid into transcript mode. In this mode the list or grid will always scroll 5911 * to the bottom to show new items. 5912 * 5913 * @param mode the transcript mode to set 5914 * 5915 * @see #TRANSCRIPT_MODE_DISABLED 5916 * @see #TRANSCRIPT_MODE_NORMAL 5917 * @see #TRANSCRIPT_MODE_ALWAYS_SCROLL 5918 */ 5919 public void setTranscriptMode(int mode) { 5920 mTranscriptMode = mode; 5921 } 5922 5923 /** 5924 * Returns the current transcript mode. 5925 * 5926 * @return {@link #TRANSCRIPT_MODE_DISABLED}, {@link #TRANSCRIPT_MODE_NORMAL} or 5927 * {@link #TRANSCRIPT_MODE_ALWAYS_SCROLL} 5928 */ 5929 public int getTranscriptMode() { 5930 return mTranscriptMode; 5931 } 5932 5933 @Override 5934 public int getSolidColor() { 5935 return mCacheColorHint; 5936 } 5937 5938 /** 5939 * When set to a non-zero value, the cache color hint indicates that this list is always drawn 5940 * on top of a solid, single-color, opaque background. 5941 * 5942 * Zero means that what's behind this object is translucent (non solid) or is not made of a 5943 * single color. This hint will not affect any existing background drawable set on this view ( 5944 * typically set via {@link #setBackgroundDrawable(Drawable)}). 5945 * 5946 * @param color The background color 5947 */ 5948 public void setCacheColorHint(int color) { 5949 if (color != mCacheColorHint) { 5950 mCacheColorHint = color; 5951 int count = getChildCount(); 5952 for (int i = 0; i < count; i++) { 5953 getChildAt(i).setDrawingCacheBackgroundColor(color); 5954 } 5955 mRecycler.setCacheColorHint(color); 5956 } 5957 } 5958 5959 /** 5960 * When set to a non-zero value, the cache color hint indicates that this list is always drawn 5961 * on top of a solid, single-color, opaque background 5962 * 5963 * @return The cache color hint 5964 */ 5965 @ViewDebug.ExportedProperty(category = "drawing") 5966 public int getCacheColorHint() { 5967 return mCacheColorHint; 5968 } 5969 5970 /** 5971 * Move all views (excluding headers and footers) held by this AbsListView into the supplied 5972 * List. This includes views displayed on the screen as well as views stored in AbsListView's 5973 * internal view recycler. 5974 * 5975 * @param views A list into which to put the reclaimed views 5976 */ 5977 public void reclaimViews(List<View> views) { 5978 int childCount = getChildCount(); 5979 RecyclerListener listener = mRecycler.mRecyclerListener; 5980 5981 // Reclaim views on screen 5982 for (int i = 0; i < childCount; i++) { 5983 View child = getChildAt(i); 5984 AbsListView.LayoutParams lp = (AbsListView.LayoutParams) child.getLayoutParams(); 5985 // Don't reclaim header or footer views, or views that should be ignored 5986 if (lp != null && mRecycler.shouldRecycleViewType(lp.viewType)) { 5987 views.add(child); 5988 child.setAccessibilityDelegate(null); 5989 if (listener != null) { 5990 // Pretend they went through the scrap heap 5991 listener.onMovedToScrapHeap(child); 5992 } 5993 } 5994 } 5995 mRecycler.reclaimScrapViews(views); 5996 removeAllViewsInLayout(); 5997 } 5998 5999 private void finishGlows() { 6000 if (mEdgeGlowTop != null) { 6001 mEdgeGlowTop.finish(); 6002 mEdgeGlowBottom.finish(); 6003 } 6004 } 6005 6006 /** 6007 * Sets up this AbsListView to use a remote views adapter which connects to a RemoteViewsService 6008 * through the specified intent. 6009 * @param intent the intent used to identify the RemoteViewsService for the adapter to connect to. 6010 */ 6011 public void setRemoteViewsAdapter(Intent intent) { 6012 // Ensure that we don't already have a RemoteViewsAdapter that is bound to an existing 6013 // service handling the specified intent. 6014 if (mRemoteAdapter != null) { 6015 Intent.FilterComparison fcNew = new Intent.FilterComparison(intent); 6016 Intent.FilterComparison fcOld = new Intent.FilterComparison( 6017 mRemoteAdapter.getRemoteViewsServiceIntent()); 6018 if (fcNew.equals(fcOld)) { 6019 return; 6020 } 6021 } 6022 mDeferNotifyDataSetChanged = false; 6023 // Otherwise, create a new RemoteViewsAdapter for binding 6024 mRemoteAdapter = new RemoteViewsAdapter(getContext(), intent, this); 6025 if (mRemoteAdapter.isDataReady()) { 6026 setAdapter(mRemoteAdapter); 6027 } 6028 } 6029 6030 /** 6031 * Sets up the onClickHandler to be used by the RemoteViewsAdapter when inflating RemoteViews 6032 * 6033 * @param handler The OnClickHandler to use when inflating RemoteViews. 6034 * 6035 * @hide 6036 */ 6037 public void setRemoteViewsOnClickHandler(OnClickHandler handler) { 6038 // Ensure that we don't already have a RemoteViewsAdapter that is bound to an existing 6039 // service handling the specified intent. 6040 if (mRemoteAdapter != null) { 6041 mRemoteAdapter.setRemoteViewsOnClickHandler(handler); 6042 } 6043 } 6044 6045 /** 6046 * This defers a notifyDataSetChanged on the pending RemoteViewsAdapter if it has not 6047 * connected yet. 6048 */ 6049 @Override 6050 public void deferNotifyDataSetChanged() { 6051 mDeferNotifyDataSetChanged = true; 6052 } 6053 6054 /** 6055 * Called back when the adapter connects to the RemoteViewsService. 6056 */ 6057 @Override 6058 public boolean onRemoteAdapterConnected() { 6059 if (mRemoteAdapter != mAdapter) { 6060 setAdapter(mRemoteAdapter); 6061 if (mDeferNotifyDataSetChanged) { 6062 mRemoteAdapter.notifyDataSetChanged(); 6063 mDeferNotifyDataSetChanged = false; 6064 } 6065 return false; 6066 } else if (mRemoteAdapter != null) { 6067 mRemoteAdapter.superNotifyDataSetChanged(); 6068 return true; 6069 } 6070 return false; 6071 } 6072 6073 /** 6074 * Called back when the adapter disconnects from the RemoteViewsService. 6075 */ 6076 @Override 6077 public void onRemoteAdapterDisconnected() { 6078 // If the remote adapter disconnects, we keep it around 6079 // since the currently displayed items are still cached. 6080 // Further, we want the service to eventually reconnect 6081 // when necessary, as triggered by this view requesting 6082 // items from the Adapter. 6083 } 6084 6085 /** 6086 * Hints the RemoteViewsAdapter, if it exists, about which views are currently 6087 * being displayed by the AbsListView. 6088 */ 6089 void setVisibleRangeHint(int start, int end) { 6090 if (mRemoteAdapter != null) { 6091 mRemoteAdapter.setVisibleRangeHint(start, end); 6092 } 6093 } 6094 6095 /** 6096 * Sets the recycler listener to be notified whenever a View is set aside in 6097 * the recycler for later reuse. This listener can be used to free resources 6098 * associated to the View. 6099 * 6100 * @param listener The recycler listener to be notified of views set aside 6101 * in the recycler. 6102 * 6103 * @see android.widget.AbsListView.RecycleBin 6104 * @see android.widget.AbsListView.RecyclerListener 6105 */ 6106 public void setRecyclerListener(RecyclerListener listener) { 6107 mRecycler.mRecyclerListener = listener; 6108 } 6109 6110 class AdapterDataSetObserver extends AdapterView<ListAdapter>.AdapterDataSetObserver { 6111 @Override 6112 public void onChanged() { 6113 super.onChanged(); 6114 if (mFastScroll != null) { 6115 mFastScroll.onSectionsChanged(); 6116 } 6117 } 6118 6119 @Override 6120 public void onInvalidated() { 6121 super.onInvalidated(); 6122 if (mFastScroll != null) { 6123 mFastScroll.onSectionsChanged(); 6124 } 6125 } 6126 } 6127 6128 /** 6129 * A MultiChoiceModeListener receives events for {@link AbsListView#CHOICE_MODE_MULTIPLE_MODAL}. 6130 * It acts as the {@link ActionMode.Callback} for the selection mode and also receives 6131 * {@link #onItemCheckedStateChanged(ActionMode, int, long, boolean)} events when the user 6132 * selects and deselects list items. 6133 */ 6134 public interface MultiChoiceModeListener extends ActionMode.Callback { 6135 /** 6136 * Called when an item is checked or unchecked during selection mode. 6137 * 6138 * @param mode The {@link ActionMode} providing the selection mode 6139 * @param position Adapter position of the item that was checked or unchecked 6140 * @param id Adapter ID of the item that was checked or unchecked 6141 * @param checked <code>true</code> if the item is now checked, <code>false</code> 6142 * if the item is now unchecked. 6143 */ 6144 public void onItemCheckedStateChanged(ActionMode mode, 6145 int position, long id, boolean checked); 6146 } 6147 6148 class MultiChoiceModeWrapper implements MultiChoiceModeListener { 6149 private MultiChoiceModeListener mWrapped; 6150 6151 public void setWrapped(MultiChoiceModeListener wrapped) { 6152 mWrapped = wrapped; 6153 } 6154 6155 public boolean hasWrappedCallback() { 6156 return mWrapped != null; 6157 } 6158 6159 @Override 6160 public boolean onCreateActionMode(ActionMode mode, Menu menu) { 6161 if (mWrapped.onCreateActionMode(mode, menu)) { 6162 // Initialize checked graphic state? 6163 setLongClickable(false); 6164 return true; 6165 } 6166 return false; 6167 } 6168 6169 @Override 6170 public boolean onPrepareActionMode(ActionMode mode, Menu menu) { 6171 return mWrapped.onPrepareActionMode(mode, menu); 6172 } 6173 6174 @Override 6175 public boolean onActionItemClicked(ActionMode mode, MenuItem item) { 6176 return mWrapped.onActionItemClicked(mode, item); 6177 } 6178 6179 @Override 6180 public void onDestroyActionMode(ActionMode mode) { 6181 mWrapped.onDestroyActionMode(mode); 6182 mChoiceActionMode = null; 6183 6184 // Ending selection mode means deselecting everything. 6185 clearChoices(); 6186 6187 mDataChanged = true; 6188 rememberSyncState(); 6189 requestLayout(); 6190 6191 setLongClickable(true); 6192 } 6193 6194 @Override 6195 public void onItemCheckedStateChanged(ActionMode mode, 6196 int position, long id, boolean checked) { 6197 mWrapped.onItemCheckedStateChanged(mode, position, id, checked); 6198 6199 // If there are no items selected we no longer need the selection mode. 6200 if (getCheckedItemCount() == 0) { 6201 mode.finish(); 6202 } 6203 } 6204 } 6205 6206 /** 6207 * AbsListView extends LayoutParams to provide a place to hold the view type. 6208 */ 6209 public static class LayoutParams extends ViewGroup.LayoutParams { 6210 /** 6211 * View type for this view, as returned by 6212 * {@link android.widget.Adapter#getItemViewType(int) } 6213 */ 6214 @ViewDebug.ExportedProperty(category = "list", mapping = { 6215 @ViewDebug.IntToString(from = ITEM_VIEW_TYPE_IGNORE, to = "ITEM_VIEW_TYPE_IGNORE"), 6216 @ViewDebug.IntToString(from = ITEM_VIEW_TYPE_HEADER_OR_FOOTER, to = "ITEM_VIEW_TYPE_HEADER_OR_FOOTER") 6217 }) 6218 int viewType; 6219 6220 /** 6221 * When this boolean is set, the view has been added to the AbsListView 6222 * at least once. It is used to know whether headers/footers have already 6223 * been added to the list view and whether they should be treated as 6224 * recycled views or not. 6225 */ 6226 @ViewDebug.ExportedProperty(category = "list") 6227 boolean recycledHeaderFooter; 6228 6229 /** 6230 * When an AbsListView is measured with an AT_MOST measure spec, it needs 6231 * to obtain children views to measure itself. When doing so, the children 6232 * are not attached to the window, but put in the recycler which assumes 6233 * they've been attached before. Setting this flag will force the reused 6234 * view to be attached to the window rather than just attached to the 6235 * parent. 6236 */ 6237 @ViewDebug.ExportedProperty(category = "list") 6238 boolean forceAdd; 6239 6240 /** 6241 * The position the view was removed from when pulled out of the 6242 * scrap heap. 6243 * @hide 6244 */ 6245 int scrappedFromPosition; 6246 6247 /** 6248 * The ID the view represents 6249 */ 6250 long itemId = -1; 6251 6252 public LayoutParams(Context c, AttributeSet attrs) { 6253 super(c, attrs); 6254 } 6255 6256 public LayoutParams(int w, int h) { 6257 super(w, h); 6258 } 6259 6260 public LayoutParams(int w, int h, int viewType) { 6261 super(w, h); 6262 this.viewType = viewType; 6263 } 6264 6265 public LayoutParams(ViewGroup.LayoutParams source) { 6266 super(source); 6267 } 6268 } 6269 6270 /** 6271 * A RecyclerListener is used to receive a notification whenever a View is placed 6272 * inside the RecycleBin's scrap heap. This listener is used to free resources 6273 * associated to Views placed in the RecycleBin. 6274 * 6275 * @see android.widget.AbsListView.RecycleBin 6276 * @see android.widget.AbsListView#setRecyclerListener(android.widget.AbsListView.RecyclerListener) 6277 */ 6278 public static interface RecyclerListener { 6279 /** 6280 * Indicates that the specified View was moved into the recycler's scrap heap. 6281 * The view is not displayed on screen any more and any expensive resource 6282 * associated with the view should be discarded. 6283 * 6284 * @param view 6285 */ 6286 void onMovedToScrapHeap(View view); 6287 } 6288 6289 /** 6290 * The RecycleBin facilitates reuse of views across layouts. The RecycleBin has two levels of 6291 * storage: ActiveViews and ScrapViews. ActiveViews are those views which were onscreen at the 6292 * start of a layout. By construction, they are displaying current information. At the end of 6293 * layout, all views in ActiveViews are demoted to ScrapViews. ScrapViews are old views that 6294 * could potentially be used by the adapter to avoid allocating views unnecessarily. 6295 * 6296 * @see android.widget.AbsListView#setRecyclerListener(android.widget.AbsListView.RecyclerListener) 6297 * @see android.widget.AbsListView.RecyclerListener 6298 */ 6299 class RecycleBin { 6300 private RecyclerListener mRecyclerListener; 6301 6302 /** 6303 * The position of the first view stored in mActiveViews. 6304 */ 6305 private int mFirstActivePosition; 6306 6307 /** 6308 * Views that were on screen at the start of layout. This array is populated at the start of 6309 * layout, and at the end of layout all view in mActiveViews are moved to mScrapViews. 6310 * Views in mActiveViews represent a contiguous range of Views, with position of the first 6311 * view store in mFirstActivePosition. 6312 */ 6313 private View[] mActiveViews = new View[0]; 6314 6315 /** 6316 * Unsorted views that can be used by the adapter as a convert view. 6317 */ 6318 private ArrayList<View>[] mScrapViews; 6319 6320 private int mViewTypeCount; 6321 6322 private ArrayList<View> mCurrentScrap; 6323 6324 private ArrayList<View> mSkippedScrap; 6325 6326 private SparseArray<View> mTransientStateViews; 6327 private LongSparseArray<View> mTransientStateViewsById; 6328 6329 public void setViewTypeCount(int viewTypeCount) { 6330 if (viewTypeCount < 1) { 6331 throw new IllegalArgumentException("Can't have a viewTypeCount < 1"); 6332 } 6333 //noinspection unchecked 6334 ArrayList<View>[] scrapViews = new ArrayList[viewTypeCount]; 6335 for (int i = 0; i < viewTypeCount; i++) { 6336 scrapViews[i] = new ArrayList<View>(); 6337 } 6338 mViewTypeCount = viewTypeCount; 6339 mCurrentScrap = scrapViews[0]; 6340 mScrapViews = scrapViews; 6341 } 6342 6343 public void markChildrenDirty() { 6344 if (mViewTypeCount == 1) { 6345 final ArrayList<View> scrap = mCurrentScrap; 6346 final int scrapCount = scrap.size(); 6347 for (int i = 0; i < scrapCount; i++) { 6348 scrap.get(i).forceLayout(); 6349 } 6350 } else { 6351 final int typeCount = mViewTypeCount; 6352 for (int i = 0; i < typeCount; i++) { 6353 final ArrayList<View> scrap = mScrapViews[i]; 6354 final int scrapCount = scrap.size(); 6355 for (int j = 0; j < scrapCount; j++) { 6356 scrap.get(j).forceLayout(); 6357 } 6358 } 6359 } 6360 if (mTransientStateViews != null) { 6361 final int count = mTransientStateViews.size(); 6362 for (int i = 0; i < count; i++) { 6363 mTransientStateViews.valueAt(i).forceLayout(); 6364 } 6365 } 6366 if (mTransientStateViewsById != null) { 6367 final int count = mTransientStateViewsById.size(); 6368 for (int i = 0; i < count; i++) { 6369 mTransientStateViewsById.valueAt(i).forceLayout(); 6370 } 6371 } 6372 } 6373 6374 public boolean shouldRecycleViewType(int viewType) { 6375 return viewType >= 0; 6376 } 6377 6378 /** 6379 * Clears the scrap heap. 6380 */ 6381 void clear() { 6382 if (mViewTypeCount == 1) { 6383 final ArrayList<View> scrap = mCurrentScrap; 6384 clearScrap(scrap); 6385 } else { 6386 final int typeCount = mViewTypeCount; 6387 for (int i = 0; i < typeCount; i++) { 6388 final ArrayList<View> scrap = mScrapViews[i]; 6389 clearScrap(scrap); 6390 } 6391 } 6392 6393 clearTransientStateViews(); 6394 } 6395 6396 /** 6397 * Fill ActiveViews with all of the children of the AbsListView. 6398 * 6399 * @param childCount The minimum number of views mActiveViews should hold 6400 * @param firstActivePosition The position of the first view that will be stored in 6401 * mActiveViews 6402 */ 6403 void fillActiveViews(int childCount, int firstActivePosition) { 6404 if (mActiveViews.length < childCount) { 6405 mActiveViews = new View[childCount]; 6406 } 6407 mFirstActivePosition = firstActivePosition; 6408 6409 //noinspection MismatchedReadAndWriteOfArray 6410 final View[] activeViews = mActiveViews; 6411 for (int i = 0; i < childCount; i++) { 6412 View child = getChildAt(i); 6413 AbsListView.LayoutParams lp = (AbsListView.LayoutParams) child.getLayoutParams(); 6414 // Don't put header or footer views into the scrap heap 6415 if (lp != null && lp.viewType != ITEM_VIEW_TYPE_HEADER_OR_FOOTER) { 6416 // Note: We do place AdapterView.ITEM_VIEW_TYPE_IGNORE in active views. 6417 // However, we will NOT place them into scrap views. 6418 activeViews[i] = child; 6419 } 6420 } 6421 } 6422 6423 /** 6424 * Get the view corresponding to the specified position. The view will be removed from 6425 * mActiveViews if it is found. 6426 * 6427 * @param position The position to look up in mActiveViews 6428 * @return The view if it is found, null otherwise 6429 */ 6430 View getActiveView(int position) { 6431 int index = position - mFirstActivePosition; 6432 final View[] activeViews = mActiveViews; 6433 if (index >=0 && index < activeViews.length) { 6434 final View match = activeViews[index]; 6435 activeViews[index] = null; 6436 return match; 6437 } 6438 return null; 6439 } 6440 6441 View getTransientStateView(int position) { 6442 if (mAdapter != null && mAdapterHasStableIds && mTransientStateViewsById != null) { 6443 long id = mAdapter.getItemId(position); 6444 View result = mTransientStateViewsById.get(id); 6445 mTransientStateViewsById.remove(id); 6446 return result; 6447 } 6448 if (mTransientStateViews != null) { 6449 final int index = mTransientStateViews.indexOfKey(position); 6450 if (index >= 0) { 6451 View result = mTransientStateViews.valueAt(index); 6452 mTransientStateViews.removeAt(index); 6453 return result; 6454 } 6455 } 6456 return null; 6457 } 6458 6459 /** 6460 * Dumps and fully detaches any currently saved views with transient 6461 * state. 6462 */ 6463 void clearTransientStateViews() { 6464 final SparseArray<View> viewsByPos = mTransientStateViews; 6465 if (viewsByPos != null) { 6466 final int N = viewsByPos.size(); 6467 for (int i = 0; i < N; i++) { 6468 removeDetachedView(viewsByPos.valueAt(i), false); 6469 } 6470 viewsByPos.clear(); 6471 } 6472 6473 final LongSparseArray<View> viewsById = mTransientStateViewsById; 6474 if (viewsById != null) { 6475 final int N = viewsById.size(); 6476 for (int i = 0; i < N; i++) { 6477 removeDetachedView(viewsById.valueAt(i), false); 6478 } 6479 viewsById.clear(); 6480 } 6481 } 6482 6483 /** 6484 * @return A view from the ScrapViews collection. These are unordered. 6485 */ 6486 View getScrapView(int position) { 6487 if (mViewTypeCount == 1) { 6488 return retrieveFromScrap(mCurrentScrap, position); 6489 } else { 6490 final int whichScrap = mAdapter.getItemViewType(position); 6491 if (whichScrap >= 0 && whichScrap < mScrapViews.length) { 6492 return retrieveFromScrap(mScrapViews[whichScrap], position); 6493 } 6494 } 6495 return null; 6496 } 6497 6498 /** 6499 * Puts a view into the list of scrap views. 6500 * <p> 6501 * If the list data hasn't changed or the adapter has stable IDs, views 6502 * with transient state will be preserved for later retrieval. 6503 * 6504 * @param scrap The view to add 6505 * @param position The view's position within its parent 6506 */ 6507 void addScrapView(View scrap, int position) { 6508 final AbsListView.LayoutParams lp = (AbsListView.LayoutParams) scrap.getLayoutParams(); 6509 if (lp == null) { 6510 return; 6511 } 6512 6513 lp.scrappedFromPosition = position; 6514 6515 // Remove but don't scrap header or footer views, or views that 6516 // should otherwise not be recycled. 6517 final int viewType = lp.viewType; 6518 if (!shouldRecycleViewType(viewType)) { 6519 return; 6520 } 6521 6522 scrap.dispatchStartTemporaryDetach(); 6523 6524 // The the accessibility state of the view may change while temporary 6525 // detached and we do not allow detached views to fire accessibility 6526 // events. So we are announcing that the subtree changed giving a chance 6527 // to clients holding on to a view in this subtree to refresh it. 6528 notifyViewAccessibilityStateChangedIfNeeded( 6529 AccessibilityEvent.CONTENT_CHANGE_TYPE_SUBTREE); 6530 6531 // Don't scrap views that have transient state. 6532 final boolean scrapHasTransientState = scrap.hasTransientState(); 6533 if (scrapHasTransientState) { 6534 if (mAdapter != null && mAdapterHasStableIds) { 6535 // If the adapter has stable IDs, we can reuse the view for 6536 // the same data. 6537 if (mTransientStateViewsById == null) { 6538 mTransientStateViewsById = new LongSparseArray<View>(); 6539 } 6540 mTransientStateViewsById.put(lp.itemId, scrap); 6541 } else if (!mDataChanged) { 6542 // If the data hasn't changed, we can reuse the views at 6543 // their old positions. 6544 if (mTransientStateViews == null) { 6545 mTransientStateViews = new SparseArray<View>(); 6546 } 6547 mTransientStateViews.put(position, scrap); 6548 } else { 6549 // Otherwise, we'll have to remove the view and start over. 6550 if (mSkippedScrap == null) { 6551 mSkippedScrap = new ArrayList<View>(); 6552 } 6553 mSkippedScrap.add(scrap); 6554 } 6555 } else { 6556 if (mViewTypeCount == 1) { 6557 mCurrentScrap.add(scrap); 6558 } else { 6559 mScrapViews[viewType].add(scrap); 6560 } 6561 6562 if (mRecyclerListener != null) { 6563 mRecyclerListener.onMovedToScrapHeap(scrap); 6564 } 6565 } 6566 } 6567 6568 /** 6569 * Finish the removal of any views that skipped the scrap heap. 6570 */ 6571 void removeSkippedScrap() { 6572 if (mSkippedScrap == null) { 6573 return; 6574 } 6575 final int count = mSkippedScrap.size(); 6576 for (int i = 0; i < count; i++) { 6577 removeDetachedView(mSkippedScrap.get(i), false); 6578 } 6579 mSkippedScrap.clear(); 6580 } 6581 6582 /** 6583 * Move all views remaining in mActiveViews to mScrapViews. 6584 */ 6585 void scrapActiveViews() { 6586 final View[] activeViews = mActiveViews; 6587 final boolean hasListener = mRecyclerListener != null; 6588 final boolean multipleScraps = mViewTypeCount > 1; 6589 6590 ArrayList<View> scrapViews = mCurrentScrap; 6591 final int count = activeViews.length; 6592 for (int i = count - 1; i >= 0; i--) { 6593 final View victim = activeViews[i]; 6594 if (victim != null) { 6595 final AbsListView.LayoutParams lp 6596 = (AbsListView.LayoutParams) victim.getLayoutParams(); 6597 final int whichScrap = lp.viewType; 6598 6599 activeViews[i] = null; 6600 6601 if (victim.hasTransientState()) { 6602 // Store views with transient state for later use. 6603 victim.dispatchStartTemporaryDetach(); 6604 6605 if (mAdapter != null && mAdapterHasStableIds) { 6606 if (mTransientStateViewsById == null) { 6607 mTransientStateViewsById = new LongSparseArray<View>(); 6608 } 6609 long id = mAdapter.getItemId(mFirstActivePosition + i); 6610 mTransientStateViewsById.put(id, victim); 6611 } else if (!mDataChanged) { 6612 if (mTransientStateViews == null) { 6613 mTransientStateViews = new SparseArray<View>(); 6614 } 6615 mTransientStateViews.put(mFirstActivePosition + i, victim); 6616 } else if (whichScrap != ITEM_VIEW_TYPE_HEADER_OR_FOOTER) { 6617 // The data has changed, we can't keep this view. 6618 removeDetachedView(victim, false); 6619 } 6620 } else if (!shouldRecycleViewType(whichScrap)) { 6621 // Discard non-recyclable views except headers/footers. 6622 if (whichScrap != ITEM_VIEW_TYPE_HEADER_OR_FOOTER) { 6623 removeDetachedView(victim, false); 6624 } 6625 } else { 6626 // Store everything else on the appropriate scrap heap. 6627 if (multipleScraps) { 6628 scrapViews = mScrapViews[whichScrap]; 6629 } 6630 6631 victim.dispatchStartTemporaryDetach(); 6632 lp.scrappedFromPosition = mFirstActivePosition + i; 6633 scrapViews.add(victim); 6634 6635 if (hasListener) { 6636 mRecyclerListener.onMovedToScrapHeap(victim); 6637 } 6638 } 6639 } 6640 } 6641 6642 pruneScrapViews(); 6643 } 6644 6645 /** 6646 * Makes sure that the size of mScrapViews does not exceed the size of 6647 * mActiveViews, which can happen if an adapter does not recycle its 6648 * views. Removes cached transient state views that no longer have 6649 * transient state. 6650 */ 6651 private void pruneScrapViews() { 6652 final int maxViews = mActiveViews.length; 6653 final int viewTypeCount = mViewTypeCount; 6654 final ArrayList<View>[] scrapViews = mScrapViews; 6655 for (int i = 0; i < viewTypeCount; ++i) { 6656 final ArrayList<View> scrapPile = scrapViews[i]; 6657 int size = scrapPile.size(); 6658 final int extras = size - maxViews; 6659 size--; 6660 for (int j = 0; j < extras; j++) { 6661 removeDetachedView(scrapPile.remove(size--), false); 6662 } 6663 } 6664 6665 final SparseArray<View> transViewsByPos = mTransientStateViews; 6666 if (transViewsByPos != null) { 6667 for (int i = 0; i < transViewsByPos.size(); i++) { 6668 final View v = transViewsByPos.valueAt(i); 6669 if (!v.hasTransientState()) { 6670 removeDetachedView(v, false); 6671 transViewsByPos.removeAt(i); 6672 i--; 6673 } 6674 } 6675 } 6676 6677 final LongSparseArray<View> transViewsById = mTransientStateViewsById; 6678 if (transViewsById != null) { 6679 for (int i = 0; i < transViewsById.size(); i++) { 6680 final View v = transViewsById.valueAt(i); 6681 if (!v.hasTransientState()) { 6682 removeDetachedView(v, false); 6683 transViewsById.removeAt(i); 6684 i--; 6685 } 6686 } 6687 } 6688 } 6689 6690 /** 6691 * Puts all views in the scrap heap into the supplied list. 6692 */ 6693 void reclaimScrapViews(List<View> views) { 6694 if (mViewTypeCount == 1) { 6695 views.addAll(mCurrentScrap); 6696 } else { 6697 final int viewTypeCount = mViewTypeCount; 6698 final ArrayList<View>[] scrapViews = mScrapViews; 6699 for (int i = 0; i < viewTypeCount; ++i) { 6700 final ArrayList<View> scrapPile = scrapViews[i]; 6701 views.addAll(scrapPile); 6702 } 6703 } 6704 } 6705 6706 /** 6707 * Updates the cache color hint of all known views. 6708 * 6709 * @param color The new cache color hint. 6710 */ 6711 void setCacheColorHint(int color) { 6712 if (mViewTypeCount == 1) { 6713 final ArrayList<View> scrap = mCurrentScrap; 6714 final int scrapCount = scrap.size(); 6715 for (int i = 0; i < scrapCount; i++) { 6716 scrap.get(i).setDrawingCacheBackgroundColor(color); 6717 } 6718 } else { 6719 final int typeCount = mViewTypeCount; 6720 for (int i = 0; i < typeCount; i++) { 6721 final ArrayList<View> scrap = mScrapViews[i]; 6722 final int scrapCount = scrap.size(); 6723 for (int j = 0; j < scrapCount; j++) { 6724 scrap.get(j).setDrawingCacheBackgroundColor(color); 6725 } 6726 } 6727 } 6728 // Just in case this is called during a layout pass 6729 final View[] activeViews = mActiveViews; 6730 final int count = activeViews.length; 6731 for (int i = 0; i < count; ++i) { 6732 final View victim = activeViews[i]; 6733 if (victim != null) { 6734 victim.setDrawingCacheBackgroundColor(color); 6735 } 6736 } 6737 } 6738 6739 private View retrieveFromScrap(ArrayList<View> scrapViews, int position) { 6740 final int size = scrapViews.size(); 6741 if (size > 0) { 6742 // See if we still have a view for this position or ID. 6743 for (int i = 0; i < size; i++) { 6744 final View view = scrapViews.get(i); 6745 final AbsListView.LayoutParams params = 6746 (AbsListView.LayoutParams) view.getLayoutParams(); 6747 6748 if (mAdapterHasStableIds) { 6749 final long id = mAdapter.getItemId(position); 6750 if (id == params.itemId) { 6751 return scrapViews.remove(i); 6752 } 6753 } else if (params.scrappedFromPosition == position) { 6754 final View scrap = scrapViews.remove(i); 6755 clearAccessibilityFromScrap(scrap); 6756 return scrap; 6757 } 6758 } 6759 final View scrap = scrapViews.remove(size - 1); 6760 clearAccessibilityFromScrap(scrap); 6761 return scrap; 6762 } else { 6763 return null; 6764 } 6765 } 6766 6767 private void clearScrap(final ArrayList<View> scrap) { 6768 final int scrapCount = scrap.size(); 6769 for (int j = 0; j < scrapCount; j++) { 6770 removeDetachedView(scrap.remove(scrapCount - 1 - j), false); 6771 } 6772 } 6773 6774 private void clearAccessibilityFromScrap(View view) { 6775 view.clearAccessibilityFocus(); 6776 view.setAccessibilityDelegate(null); 6777 } 6778 6779 private void removeDetachedView(View child, boolean animate) { 6780 child.setAccessibilityDelegate(null); 6781 AbsListView.this.removeDetachedView(child, animate); 6782 } 6783 } 6784 6785 /** 6786 * Returns the height of the view for the specified position. 6787 * 6788 * @param position the item position 6789 * @return view height in pixels 6790 */ 6791 int getHeightForPosition(int position) { 6792 final int firstVisiblePosition = getFirstVisiblePosition(); 6793 final int childCount = getChildCount(); 6794 final int index = position - firstVisiblePosition; 6795 if (index >= 0 && index < childCount) { 6796 // Position is on-screen, use existing view. 6797 final View view = getChildAt(index); 6798 return view.getHeight(); 6799 } else { 6800 // Position is off-screen, obtain & recycle view. 6801 final View view = obtainView(position, mIsScrap); 6802 view.measure(mWidthMeasureSpec, MeasureSpec.UNSPECIFIED); 6803 final int height = view.getMeasuredHeight(); 6804 mRecycler.addScrapView(view, position); 6805 return height; 6806 } 6807 } 6808 6809 /** 6810 * Sets the selected item and positions the selection y pixels from the top edge 6811 * of the ListView. (If in touch mode, the item will not be selected but it will 6812 * still be positioned appropriately.) 6813 * 6814 * @param position Index (starting at 0) of the data item to be selected. 6815 * @param y The distance from the top edge of the ListView (plus padding) that the 6816 * item will be positioned. 6817 */ 6818 public void setSelectionFromTop(int position, int y) { 6819 if (mAdapter == null) { 6820 return; 6821 } 6822 6823 if (!isInTouchMode()) { 6824 position = lookForSelectablePosition(position, true); 6825 if (position >= 0) { 6826 setNextSelectedPositionInt(position); 6827 } 6828 } else { 6829 mResurrectToPosition = position; 6830 } 6831 6832 if (position >= 0) { 6833 mLayoutMode = LAYOUT_SPECIFIC; 6834 mSpecificTop = mListPadding.top + y; 6835 6836 if (mNeedSync) { 6837 mSyncPosition = position; 6838 mSyncRowId = mAdapter.getItemId(position); 6839 } 6840 6841 if (mPositionScroller != null) { 6842 mPositionScroller.stop(); 6843 } 6844 requestLayout(); 6845 } 6846 } 6847 6848 /** 6849 * Abstract positon scroller used to handle smooth scrolling. 6850 */ 6851 static abstract class AbsPositionScroller { 6852 public abstract void start(int position); 6853 public abstract void start(int position, int boundPosition); 6854 public abstract void startWithOffset(int position, int offset); 6855 public abstract void startWithOffset(int position, int offset, int duration); 6856 public abstract void stop(); 6857 } 6858 6859 /** 6860 * Default position scroller that simulates a fling. 6861 */ 6862 class PositionScroller extends AbsPositionScroller implements Runnable { 6863 private static final int SCROLL_DURATION = 200; 6864 6865 private static final int MOVE_DOWN_POS = 1; 6866 private static final int MOVE_UP_POS = 2; 6867 private static final int MOVE_DOWN_BOUND = 3; 6868 private static final int MOVE_UP_BOUND = 4; 6869 private static final int MOVE_OFFSET = 5; 6870 6871 private int mMode; 6872 private int mTargetPos; 6873 private int mBoundPos; 6874 private int mLastSeenPos; 6875 private int mScrollDuration; 6876 private final int mExtraScroll; 6877 6878 private int mOffsetFromTop; 6879 6880 PositionScroller() { 6881 mExtraScroll = ViewConfiguration.get(mContext).getScaledFadingEdgeLength(); 6882 } 6883 6884 @Override 6885 public void start(final int position) { 6886 stop(); 6887 6888 if (mDataChanged) { 6889 // Wait until we're back in a stable state to try this. 6890 mPositionScrollAfterLayout = new Runnable() { 6891 @Override public void run() { 6892 start(position); 6893 } 6894 }; 6895 return; 6896 } 6897 6898 final int childCount = getChildCount(); 6899 if (childCount == 0) { 6900 // Can't scroll without children. 6901 return; 6902 } 6903 6904 final int firstPos = mFirstPosition; 6905 final int lastPos = firstPos + childCount - 1; 6906 6907 int viewTravelCount; 6908 int clampedPosition = Math.max(0, Math.min(getCount() - 1, position)); 6909 if (clampedPosition < firstPos) { 6910 viewTravelCount = firstPos - clampedPosition + 1; 6911 mMode = MOVE_UP_POS; 6912 } else if (clampedPosition > lastPos) { 6913 viewTravelCount = clampedPosition - lastPos + 1; 6914 mMode = MOVE_DOWN_POS; 6915 } else { 6916 scrollToVisible(clampedPosition, INVALID_POSITION, SCROLL_DURATION); 6917 return; 6918 } 6919 6920 if (viewTravelCount > 0) { 6921 mScrollDuration = SCROLL_DURATION / viewTravelCount; 6922 } else { 6923 mScrollDuration = SCROLL_DURATION; 6924 } 6925 mTargetPos = clampedPosition; 6926 mBoundPos = INVALID_POSITION; 6927 mLastSeenPos = INVALID_POSITION; 6928 6929 postOnAnimation(this); 6930 } 6931 6932 @Override 6933 public void start(final int position, final int boundPosition) { 6934 stop(); 6935 6936 if (boundPosition == INVALID_POSITION) { 6937 start(position); 6938 return; 6939 } 6940 6941 if (mDataChanged) { 6942 // Wait until we're back in a stable state to try this. 6943 mPositionScrollAfterLayout = new Runnable() { 6944 @Override public void run() { 6945 start(position, boundPosition); 6946 } 6947 }; 6948 return; 6949 } 6950 6951 final int childCount = getChildCount(); 6952 if (childCount == 0) { 6953 // Can't scroll without children. 6954 return; 6955 } 6956 6957 final int firstPos = mFirstPosition; 6958 final int lastPos = firstPos + childCount - 1; 6959 6960 int viewTravelCount; 6961 int clampedPosition = Math.max(0, Math.min(getCount() - 1, position)); 6962 if (clampedPosition < firstPos) { 6963 final int boundPosFromLast = lastPos - boundPosition; 6964 if (boundPosFromLast < 1) { 6965 // Moving would shift our bound position off the screen. Abort. 6966 return; 6967 } 6968 6969 final int posTravel = firstPos - clampedPosition + 1; 6970 final int boundTravel = boundPosFromLast - 1; 6971 if (boundTravel < posTravel) { 6972 viewTravelCount = boundTravel; 6973 mMode = MOVE_UP_BOUND; 6974 } else { 6975 viewTravelCount = posTravel; 6976 mMode = MOVE_UP_POS; 6977 } 6978 } else if (clampedPosition > lastPos) { 6979 final int boundPosFromFirst = boundPosition - firstPos; 6980 if (boundPosFromFirst < 1) { 6981 // Moving would shift our bound position off the screen. Abort. 6982 return; 6983 } 6984 6985 final int posTravel = clampedPosition - lastPos + 1; 6986 final int boundTravel = boundPosFromFirst - 1; 6987 if (boundTravel < posTravel) { 6988 viewTravelCount = boundTravel; 6989 mMode = MOVE_DOWN_BOUND; 6990 } else { 6991 viewTravelCount = posTravel; 6992 mMode = MOVE_DOWN_POS; 6993 } 6994 } else { 6995 scrollToVisible(clampedPosition, boundPosition, SCROLL_DURATION); 6996 return; 6997 } 6998 6999 if (viewTravelCount > 0) { 7000 mScrollDuration = SCROLL_DURATION / viewTravelCount; 7001 } else { 7002 mScrollDuration = SCROLL_DURATION; 7003 } 7004 mTargetPos = clampedPosition; 7005 mBoundPos = boundPosition; 7006 mLastSeenPos = INVALID_POSITION; 7007 7008 postOnAnimation(this); 7009 } 7010 7011 @Override 7012 public void startWithOffset(int position, int offset) { 7013 startWithOffset(position, offset, SCROLL_DURATION); 7014 } 7015 7016 @Override 7017 public void startWithOffset(final int position, int offset, final int duration) { 7018 stop(); 7019 7020 if (mDataChanged) { 7021 // Wait until we're back in a stable state to try this. 7022 final int postOffset = offset; 7023 mPositionScrollAfterLayout = new Runnable() { 7024 @Override public void run() { 7025 startWithOffset(position, postOffset, duration); 7026 } 7027 }; 7028 return; 7029 } 7030 7031 final int childCount = getChildCount(); 7032 if (childCount == 0) { 7033 // Can't scroll without children. 7034 return; 7035 } 7036 7037 offset += getPaddingTop(); 7038 7039 mTargetPos = Math.max(0, Math.min(getCount() - 1, position)); 7040 mOffsetFromTop = offset; 7041 mBoundPos = INVALID_POSITION; 7042 mLastSeenPos = INVALID_POSITION; 7043 mMode = MOVE_OFFSET; 7044 7045 final int firstPos = mFirstPosition; 7046 final int lastPos = firstPos + childCount - 1; 7047 7048 int viewTravelCount; 7049 if (mTargetPos < firstPos) { 7050 viewTravelCount = firstPos - mTargetPos; 7051 } else if (mTargetPos > lastPos) { 7052 viewTravelCount = mTargetPos - lastPos; 7053 } else { 7054 // On-screen, just scroll. 7055 final int targetTop = getChildAt(mTargetPos - firstPos).getTop(); 7056 smoothScrollBy(targetTop - offset, duration, true); 7057 return; 7058 } 7059 7060 // Estimate how many screens we should travel 7061 final float screenTravelCount = (float) viewTravelCount / childCount; 7062 mScrollDuration = screenTravelCount < 1 ? 7063 duration : (int) (duration / screenTravelCount); 7064 mLastSeenPos = INVALID_POSITION; 7065 7066 postOnAnimation(this); 7067 } 7068 7069 /** 7070 * Scroll such that targetPos is in the visible padded region without scrolling 7071 * boundPos out of view. Assumes targetPos is onscreen. 7072 */ 7073 private void scrollToVisible(int targetPos, int boundPos, int duration) { 7074 final int firstPos = mFirstPosition; 7075 final int childCount = getChildCount(); 7076 final int lastPos = firstPos + childCount - 1; 7077 final int paddedTop = mListPadding.top; 7078 final int paddedBottom = getHeight() - mListPadding.bottom; 7079 7080 if (targetPos < firstPos || targetPos > lastPos) { 7081 Log.w(TAG, "scrollToVisible called with targetPos " + targetPos + 7082 " not visible [" + firstPos + ", " + lastPos + "]"); 7083 } 7084 if (boundPos < firstPos || boundPos > lastPos) { 7085 // boundPos doesn't matter, it's already offscreen. 7086 boundPos = INVALID_POSITION; 7087 } 7088 7089 final View targetChild = getChildAt(targetPos - firstPos); 7090 final int targetTop = targetChild.getTop(); 7091 final int targetBottom = targetChild.getBottom(); 7092 int scrollBy = 0; 7093 7094 if (targetBottom > paddedBottom) { 7095 scrollBy = targetBottom - paddedBottom; 7096 } 7097 if (targetTop < paddedTop) { 7098 scrollBy = targetTop - paddedTop; 7099 } 7100 7101 if (scrollBy == 0) { 7102 return; 7103 } 7104 7105 if (boundPos >= 0) { 7106 final View boundChild = getChildAt(boundPos - firstPos); 7107 final int boundTop = boundChild.getTop(); 7108 final int boundBottom = boundChild.getBottom(); 7109 final int absScroll = Math.abs(scrollBy); 7110 7111 if (scrollBy < 0 && boundBottom + absScroll > paddedBottom) { 7112 // Don't scroll the bound view off the bottom of the screen. 7113 scrollBy = Math.max(0, boundBottom - paddedBottom); 7114 } else if (scrollBy > 0 && boundTop - absScroll < paddedTop) { 7115 // Don't scroll the bound view off the top of the screen. 7116 scrollBy = Math.min(0, boundTop - paddedTop); 7117 } 7118 } 7119 7120 smoothScrollBy(scrollBy, duration); 7121 } 7122 7123 @Override 7124 public void stop() { 7125 removeCallbacks(this); 7126 } 7127 7128 @Override 7129 public void run() { 7130 final int listHeight = getHeight(); 7131 final int firstPos = mFirstPosition; 7132 7133 switch (mMode) { 7134 case MOVE_DOWN_POS: { 7135 final int lastViewIndex = getChildCount() - 1; 7136 final int lastPos = firstPos + lastViewIndex; 7137 7138 if (lastViewIndex < 0) { 7139 return; 7140 } 7141 7142 if (lastPos == mLastSeenPos) { 7143 // No new views, let things keep going. 7144 postOnAnimation(this); 7145 return; 7146 } 7147 7148 final View lastView = getChildAt(lastViewIndex); 7149 final int lastViewHeight = lastView.getHeight(); 7150 final int lastViewTop = lastView.getTop(); 7151 final int lastViewPixelsShowing = listHeight - lastViewTop; 7152 final int extraScroll = lastPos < mItemCount - 1 ? 7153 Math.max(mListPadding.bottom, mExtraScroll) : mListPadding.bottom; 7154 7155 final int scrollBy = lastViewHeight - lastViewPixelsShowing + extraScroll; 7156 smoothScrollBy(scrollBy, mScrollDuration, true); 7157 7158 mLastSeenPos = lastPos; 7159 if (lastPos < mTargetPos) { 7160 postOnAnimation(this); 7161 } 7162 break; 7163 } 7164 7165 case MOVE_DOWN_BOUND: { 7166 final int nextViewIndex = 1; 7167 final int childCount = getChildCount(); 7168 7169 if (firstPos == mBoundPos || childCount <= nextViewIndex 7170 || firstPos + childCount >= mItemCount) { 7171 return; 7172 } 7173 final int nextPos = firstPos + nextViewIndex; 7174 7175 if (nextPos == mLastSeenPos) { 7176 // No new views, let things keep going. 7177 postOnAnimation(this); 7178 return; 7179 } 7180 7181 final View nextView = getChildAt(nextViewIndex); 7182 final int nextViewHeight = nextView.getHeight(); 7183 final int nextViewTop = nextView.getTop(); 7184 final int extraScroll = Math.max(mListPadding.bottom, mExtraScroll); 7185 if (nextPos < mBoundPos) { 7186 smoothScrollBy(Math.max(0, nextViewHeight + nextViewTop - extraScroll), 7187 mScrollDuration, true); 7188 7189 mLastSeenPos = nextPos; 7190 7191 postOnAnimation(this); 7192 } else { 7193 if (nextViewTop > extraScroll) { 7194 smoothScrollBy(nextViewTop - extraScroll, mScrollDuration, true); 7195 } 7196 } 7197 break; 7198 } 7199 7200 case MOVE_UP_POS: { 7201 if (firstPos == mLastSeenPos) { 7202 // No new views, let things keep going. 7203 postOnAnimation(this); 7204 return; 7205 } 7206 7207 final View firstView = getChildAt(0); 7208 if (firstView == null) { 7209 return; 7210 } 7211 final int firstViewTop = firstView.getTop(); 7212 final int extraScroll = firstPos > 0 ? 7213 Math.max(mExtraScroll, mListPadding.top) : mListPadding.top; 7214 7215 smoothScrollBy(firstViewTop - extraScroll, mScrollDuration, true); 7216 7217 mLastSeenPos = firstPos; 7218 7219 if (firstPos > mTargetPos) { 7220 postOnAnimation(this); 7221 } 7222 break; 7223 } 7224 7225 case MOVE_UP_BOUND: { 7226 final int lastViewIndex = getChildCount() - 2; 7227 if (lastViewIndex < 0) { 7228 return; 7229 } 7230 final int lastPos = firstPos + lastViewIndex; 7231 7232 if (lastPos == mLastSeenPos) { 7233 // No new views, let things keep going. 7234 postOnAnimation(this); 7235 return; 7236 } 7237 7238 final View lastView = getChildAt(lastViewIndex); 7239 final int lastViewHeight = lastView.getHeight(); 7240 final int lastViewTop = lastView.getTop(); 7241 final int lastViewPixelsShowing = listHeight - lastViewTop; 7242 final int extraScroll = Math.max(mListPadding.top, mExtraScroll); 7243 mLastSeenPos = lastPos; 7244 if (lastPos > mBoundPos) { 7245 smoothScrollBy(-(lastViewPixelsShowing - extraScroll), mScrollDuration, true); 7246 postOnAnimation(this); 7247 } else { 7248 final int bottom = listHeight - extraScroll; 7249 final int lastViewBottom = lastViewTop + lastViewHeight; 7250 if (bottom > lastViewBottom) { 7251 smoothScrollBy(-(bottom - lastViewBottom), mScrollDuration, true); 7252 } 7253 } 7254 break; 7255 } 7256 7257 case MOVE_OFFSET: { 7258 if (mLastSeenPos == firstPos) { 7259 // No new views, let things keep going. 7260 postOnAnimation(this); 7261 return; 7262 } 7263 7264 mLastSeenPos = firstPos; 7265 7266 final int childCount = getChildCount(); 7267 final int position = mTargetPos; 7268 final int lastPos = firstPos + childCount - 1; 7269 7270 int viewTravelCount = 0; 7271 if (position < firstPos) { 7272 viewTravelCount = firstPos - position + 1; 7273 } else if (position > lastPos) { 7274 viewTravelCount = position - lastPos; 7275 } 7276 7277 // Estimate how many screens we should travel 7278 final float screenTravelCount = (float) viewTravelCount / childCount; 7279 7280 final float modifier = Math.min(Math.abs(screenTravelCount), 1.f); 7281 if (position < firstPos) { 7282 final int distance = (int) (-getHeight() * modifier); 7283 final int duration = (int) (mScrollDuration * modifier); 7284 smoothScrollBy(distance, duration, true); 7285 postOnAnimation(this); 7286 } else if (position > lastPos) { 7287 final int distance = (int) (getHeight() * modifier); 7288 final int duration = (int) (mScrollDuration * modifier); 7289 smoothScrollBy(distance, duration, true); 7290 postOnAnimation(this); 7291 } else { 7292 // On-screen, just scroll. 7293 final int targetTop = getChildAt(position - firstPos).getTop(); 7294 final int distance = targetTop - mOffsetFromTop; 7295 final int duration = (int) (mScrollDuration * 7296 ((float) Math.abs(distance) / getHeight())); 7297 smoothScrollBy(distance, duration, true); 7298 } 7299 break; 7300 } 7301 7302 default: 7303 break; 7304 } 7305 } 7306 } 7307} 7308