AbsListView.java revision 947a96956035e1ee22a82d18aec018b9046b641b
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 // True when the popup should be hidden because of a call to 615 // dispatchDisplayHint() 616 private boolean mPopupHidden; 617 618 /** 619 * ID of the active pointer. This is used to retain consistency during 620 * drags/flings if multiple pointers are used. 621 */ 622 private int mActivePointerId = INVALID_POINTER; 623 624 /** 625 * Sentinel value for no current active pointer. 626 * Used by {@link #mActivePointerId}. 627 */ 628 private static final int INVALID_POINTER = -1; 629 630 /** 631 * Maximum distance to overscroll by during edge effects 632 */ 633 int mOverscrollDistance; 634 635 /** 636 * Maximum distance to overfling during edge effects 637 */ 638 int mOverflingDistance; 639 640 // These two EdgeGlows are always set and used together. 641 // Checking one for null is as good as checking both. 642 643 /** 644 * Tracks the state of the top edge glow. 645 */ 646 private EdgeEffect mEdgeGlowTop; 647 648 /** 649 * Tracks the state of the bottom edge glow. 650 */ 651 private EdgeEffect mEdgeGlowBottom; 652 653 /** 654 * An estimate of how many pixels are between the top of the list and 655 * the top of the first position in the adapter, based on the last time 656 * we saw it. Used to hint where to draw edge glows. 657 */ 658 private int mFirstPositionDistanceGuess; 659 660 /** 661 * An estimate of how many pixels are between the bottom of the list and 662 * the bottom of the last position in the adapter, based on the last time 663 * we saw it. Used to hint where to draw edge glows. 664 */ 665 private int mLastPositionDistanceGuess; 666 667 /** 668 * Used for determining when to cancel out of overscroll. 669 */ 670 private int mDirection = 0; 671 672 /** 673 * Tracked on measurement in transcript mode. Makes sure that we can still pin to 674 * the bottom correctly on resizes. 675 */ 676 private boolean mForceTranscriptScroll; 677 678 private int mGlowPaddingLeft; 679 private int mGlowPaddingRight; 680 681 /** 682 * Used for interacting with list items from an accessibility service. 683 */ 684 private ListItemAccessibilityDelegate mAccessibilityDelegate; 685 686 private int mLastAccessibilityScrollEventFromIndex; 687 private int mLastAccessibilityScrollEventToIndex; 688 689 /** 690 * Track the item count from the last time we handled a data change. 691 */ 692 private int mLastHandledItemCount; 693 694 /** 695 * Used for smooth scrolling at a consistent rate 696 */ 697 static final Interpolator sLinearInterpolator = new LinearInterpolator(); 698 699 /** 700 * The saved state that we will be restoring from when we next sync. 701 * Kept here so that if we happen to be asked to save our state before 702 * the sync happens, we can return this existing data rather than losing 703 * it. 704 */ 705 private SavedState mPendingSync; 706 707 /** 708 * Whether the view is in the process of detaching from its window. 709 */ 710 private boolean mIsDetaching; 711 712 /** 713 * Interface definition for a callback to be invoked when the list or grid 714 * has been scrolled. 715 */ 716 public interface OnScrollListener { 717 718 /** 719 * The view is not scrolling. Note navigating the list using the trackball counts as 720 * being in the idle state since these transitions are not animated. 721 */ 722 public static int SCROLL_STATE_IDLE = 0; 723 724 /** 725 * The user is scrolling using touch, and their finger is still on the screen 726 */ 727 public static int SCROLL_STATE_TOUCH_SCROLL = 1; 728 729 /** 730 * The user had previously been scrolling using touch and had performed a fling. The 731 * animation is now coasting to a stop 732 */ 733 public static int SCROLL_STATE_FLING = 2; 734 735 /** 736 * Callback method to be invoked while the list view or grid view is being scrolled. If the 737 * view is being scrolled, this method will be called before the next frame of the scroll is 738 * rendered. In particular, it will be called before any calls to 739 * {@link Adapter#getView(int, View, ViewGroup)}. 740 * 741 * @param view The view whose scroll state is being reported 742 * 743 * @param scrollState The current scroll state. One of 744 * {@link #SCROLL_STATE_TOUCH_SCROLL} or {@link #SCROLL_STATE_IDLE}. 745 */ 746 public void onScrollStateChanged(AbsListView view, int scrollState); 747 748 /** 749 * Callback method to be invoked when the list or grid has been scrolled. This will be 750 * called after the scroll has completed 751 * @param view The view whose scroll state is being reported 752 * @param firstVisibleItem the index of the first visible cell (ignore if 753 * visibleItemCount == 0) 754 * @param visibleItemCount the number of visible cells 755 * @param totalItemCount the number of items in the list adaptor 756 */ 757 public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, 758 int totalItemCount); 759 } 760 761 /** 762 * The top-level view of a list item can implement this interface to allow 763 * itself to modify the bounds of the selection shown for that item. 764 */ 765 public interface SelectionBoundsAdjuster { 766 /** 767 * Called to allow the list item to adjust the bounds shown for 768 * its selection. 769 * 770 * @param bounds On call, this contains the bounds the list has 771 * selected for the item (that is the bounds of the entire view). The 772 * values can be modified as desired. 773 */ 774 public void adjustListItemSelectionBounds(Rect bounds); 775 } 776 777 public AbsListView(Context context) { 778 super(context); 779 initAbsListView(); 780 781 mOwnerThread = Thread.currentThread(); 782 783 setVerticalScrollBarEnabled(true); 784 TypedArray a = context.obtainStyledAttributes(R.styleable.View); 785 initializeScrollbarsInternal(a); 786 a.recycle(); 787 } 788 789 public AbsListView(Context context, AttributeSet attrs) { 790 this(context, attrs, com.android.internal.R.attr.absListViewStyle); 791 } 792 793 public AbsListView(Context context, AttributeSet attrs, int defStyleAttr) { 794 this(context, attrs, defStyleAttr, 0); 795 } 796 797 public AbsListView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) { 798 super(context, attrs, defStyleAttr, defStyleRes); 799 initAbsListView(); 800 801 mOwnerThread = Thread.currentThread(); 802 803 final TypedArray a = context.obtainStyledAttributes( 804 attrs, com.android.internal.R.styleable.AbsListView, defStyleAttr, defStyleRes); 805 806 Drawable d = a.getDrawable(com.android.internal.R.styleable.AbsListView_listSelector); 807 if (d != null) { 808 setSelector(d); 809 } 810 811 mDrawSelectorOnTop = a.getBoolean( 812 com.android.internal.R.styleable.AbsListView_drawSelectorOnTop, false); 813 814 boolean stackFromBottom = a.getBoolean(R.styleable.AbsListView_stackFromBottom, false); 815 setStackFromBottom(stackFromBottom); 816 817 boolean scrollingCacheEnabled = a.getBoolean(R.styleable.AbsListView_scrollingCache, true); 818 setScrollingCacheEnabled(scrollingCacheEnabled); 819 820 boolean useTextFilter = a.getBoolean(R.styleable.AbsListView_textFilterEnabled, false); 821 setTextFilterEnabled(useTextFilter); 822 823 int transcriptMode = a.getInt(R.styleable.AbsListView_transcriptMode, 824 TRANSCRIPT_MODE_DISABLED); 825 setTranscriptMode(transcriptMode); 826 827 int color = a.getColor(R.styleable.AbsListView_cacheColorHint, 0); 828 setCacheColorHint(color); 829 830 boolean enableFastScroll = a.getBoolean(R.styleable.AbsListView_fastScrollEnabled, false); 831 setFastScrollEnabled(enableFastScroll); 832 833 int fastScrollStyle = a.getResourceId(R.styleable.AbsListView_fastScrollStyle, 0); 834 setFastScrollStyle(fastScrollStyle); 835 836 boolean smoothScrollbar = a.getBoolean(R.styleable.AbsListView_smoothScrollbar, true); 837 setSmoothScrollbarEnabled(smoothScrollbar); 838 839 setChoiceMode(a.getInt(R.styleable.AbsListView_choiceMode, CHOICE_MODE_NONE)); 840 setFastScrollAlwaysVisible( 841 a.getBoolean(R.styleable.AbsListView_fastScrollAlwaysVisible, false)); 842 843 a.recycle(); 844 } 845 846 private void initAbsListView() { 847 // Setting focusable in touch mode will set the focusable property to true 848 setClickable(true); 849 setFocusableInTouchMode(true); 850 setWillNotDraw(false); 851 setAlwaysDrawnWithCacheEnabled(false); 852 setScrollingCacheEnabled(true); 853 854 final ViewConfiguration configuration = ViewConfiguration.get(mContext); 855 mTouchSlop = configuration.getScaledTouchSlop(); 856 mMinimumVelocity = configuration.getScaledMinimumFlingVelocity(); 857 mMaximumVelocity = configuration.getScaledMaximumFlingVelocity(); 858 mOverscrollDistance = configuration.getScaledOverscrollDistance(); 859 mOverflingDistance = configuration.getScaledOverflingDistance(); 860 861 mDensityScale = getContext().getResources().getDisplayMetrics().density; 862 } 863 864 @Override 865 public void setOverScrollMode(int mode) { 866 if (mode != OVER_SCROLL_NEVER) { 867 if (mEdgeGlowTop == null) { 868 Context context = getContext(); 869 mEdgeGlowTop = new EdgeEffect(context); 870 mEdgeGlowBottom = new EdgeEffect(context); 871 } 872 } else { 873 mEdgeGlowTop = null; 874 mEdgeGlowBottom = null; 875 } 876 super.setOverScrollMode(mode); 877 } 878 879 /** 880 * {@inheritDoc} 881 */ 882 @Override 883 public void setAdapter(ListAdapter adapter) { 884 if (adapter != null) { 885 mAdapterHasStableIds = mAdapter.hasStableIds(); 886 if (mChoiceMode != CHOICE_MODE_NONE && mAdapterHasStableIds && 887 mCheckedIdStates == null) { 888 mCheckedIdStates = new LongSparseArray<Integer>(); 889 } 890 } 891 892 if (mCheckStates != null) { 893 mCheckStates.clear(); 894 } 895 896 if (mCheckedIdStates != null) { 897 mCheckedIdStates.clear(); 898 } 899 } 900 901 /** 902 * Returns the number of items currently selected. This will only be valid 903 * if the choice mode is not {@link #CHOICE_MODE_NONE} (default). 904 * 905 * <p>To determine the specific items that are currently selected, use one of 906 * the <code>getChecked*</code> methods. 907 * 908 * @return The number of items currently selected 909 * 910 * @see #getCheckedItemPosition() 911 * @see #getCheckedItemPositions() 912 * @see #getCheckedItemIds() 913 */ 914 public int getCheckedItemCount() { 915 return mCheckedItemCount; 916 } 917 918 /** 919 * Returns the checked state of the specified position. The result is only 920 * valid if the choice mode has been set to {@link #CHOICE_MODE_SINGLE} 921 * or {@link #CHOICE_MODE_MULTIPLE}. 922 * 923 * @param position The item whose checked state to return 924 * @return The item's checked state or <code>false</code> if choice mode 925 * is invalid 926 * 927 * @see #setChoiceMode(int) 928 */ 929 public boolean isItemChecked(int position) { 930 if (mChoiceMode != CHOICE_MODE_NONE && mCheckStates != null) { 931 return mCheckStates.get(position); 932 } 933 934 return false; 935 } 936 937 /** 938 * Returns the currently checked item. The result is only valid if the choice 939 * mode has been set to {@link #CHOICE_MODE_SINGLE}. 940 * 941 * @return The position of the currently checked item or 942 * {@link #INVALID_POSITION} if nothing is selected 943 * 944 * @see #setChoiceMode(int) 945 */ 946 public int getCheckedItemPosition() { 947 if (mChoiceMode == CHOICE_MODE_SINGLE && mCheckStates != null && mCheckStates.size() == 1) { 948 return mCheckStates.keyAt(0); 949 } 950 951 return INVALID_POSITION; 952 } 953 954 /** 955 * Returns the set of checked items in the list. The result is only valid if 956 * the choice mode has not been set to {@link #CHOICE_MODE_NONE}. 957 * 958 * @return A SparseBooleanArray which will return true for each call to 959 * get(int position) where position is a checked position in the 960 * list and false otherwise, or <code>null</code> if the choice 961 * mode is set to {@link #CHOICE_MODE_NONE}. 962 */ 963 public SparseBooleanArray getCheckedItemPositions() { 964 if (mChoiceMode != CHOICE_MODE_NONE) { 965 return mCheckStates; 966 } 967 return null; 968 } 969 970 /** 971 * Returns the set of checked items ids. The result is only valid if the 972 * choice mode has not been set to {@link #CHOICE_MODE_NONE} and the adapter 973 * has stable IDs. ({@link ListAdapter#hasStableIds()} == {@code true}) 974 * 975 * @return A new array which contains the id of each checked item in the 976 * list. 977 */ 978 public long[] getCheckedItemIds() { 979 if (mChoiceMode == CHOICE_MODE_NONE || mCheckedIdStates == null || mAdapter == null) { 980 return new long[0]; 981 } 982 983 final LongSparseArray<Integer> idStates = mCheckedIdStates; 984 final int count = idStates.size(); 985 final long[] ids = new long[count]; 986 987 for (int i = 0; i < count; i++) { 988 ids[i] = idStates.keyAt(i); 989 } 990 991 return ids; 992 } 993 994 /** 995 * Clear any choices previously set 996 */ 997 public void clearChoices() { 998 if (mCheckStates != null) { 999 mCheckStates.clear(); 1000 } 1001 if (mCheckedIdStates != null) { 1002 mCheckedIdStates.clear(); 1003 } 1004 mCheckedItemCount = 0; 1005 } 1006 1007 /** 1008 * Sets the checked state of the specified position. The is only valid if 1009 * the choice mode has been set to {@link #CHOICE_MODE_SINGLE} or 1010 * {@link #CHOICE_MODE_MULTIPLE}. 1011 * 1012 * @param position The item whose checked state is to be checked 1013 * @param value The new checked state for the item 1014 */ 1015 public void setItemChecked(int position, boolean value) { 1016 if (mChoiceMode == CHOICE_MODE_NONE) { 1017 return; 1018 } 1019 1020 // Start selection mode if needed. We don't need to if we're unchecking something. 1021 if (value && mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL && mChoiceActionMode == null) { 1022 if (mMultiChoiceModeCallback == null || 1023 !mMultiChoiceModeCallback.hasWrappedCallback()) { 1024 throw new IllegalStateException("AbsListView: attempted to start selection mode " + 1025 "for CHOICE_MODE_MULTIPLE_MODAL but no choice mode callback was " + 1026 "supplied. Call setMultiChoiceModeListener to set a callback."); 1027 } 1028 mChoiceActionMode = startActionMode(mMultiChoiceModeCallback); 1029 } 1030 1031 if (mChoiceMode == CHOICE_MODE_MULTIPLE || mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL) { 1032 boolean oldValue = mCheckStates.get(position); 1033 mCheckStates.put(position, value); 1034 if (mCheckedIdStates != null && mAdapter.hasStableIds()) { 1035 if (value) { 1036 mCheckedIdStates.put(mAdapter.getItemId(position), position); 1037 } else { 1038 mCheckedIdStates.delete(mAdapter.getItemId(position)); 1039 } 1040 } 1041 if (oldValue != value) { 1042 if (value) { 1043 mCheckedItemCount++; 1044 } else { 1045 mCheckedItemCount--; 1046 } 1047 } 1048 if (mChoiceActionMode != null) { 1049 final long id = mAdapter.getItemId(position); 1050 mMultiChoiceModeCallback.onItemCheckedStateChanged(mChoiceActionMode, 1051 position, id, value); 1052 } 1053 } else { 1054 boolean updateIds = mCheckedIdStates != null && mAdapter.hasStableIds(); 1055 // Clear all values if we're checking something, or unchecking the currently 1056 // selected item 1057 if (value || isItemChecked(position)) { 1058 mCheckStates.clear(); 1059 if (updateIds) { 1060 mCheckedIdStates.clear(); 1061 } 1062 } 1063 // this may end up selecting the value we just cleared but this way 1064 // we ensure length of mCheckStates is 1, a fact getCheckedItemPosition relies on 1065 if (value) { 1066 mCheckStates.put(position, true); 1067 if (updateIds) { 1068 mCheckedIdStates.put(mAdapter.getItemId(position), position); 1069 } 1070 mCheckedItemCount = 1; 1071 } else if (mCheckStates.size() == 0 || !mCheckStates.valueAt(0)) { 1072 mCheckedItemCount = 0; 1073 } 1074 } 1075 1076 // Do not generate a data change while we are in the layout phase 1077 if (!mInLayout && !mBlockLayoutRequests) { 1078 mDataChanged = true; 1079 rememberSyncState(); 1080 requestLayout(); 1081 } 1082 } 1083 1084 @Override 1085 public boolean performItemClick(View view, int position, long id) { 1086 boolean handled = false; 1087 boolean dispatchItemClick = true; 1088 1089 if (mChoiceMode != CHOICE_MODE_NONE) { 1090 handled = true; 1091 boolean checkedStateChanged = false; 1092 1093 if (mChoiceMode == CHOICE_MODE_MULTIPLE || 1094 (mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL && mChoiceActionMode != null)) { 1095 boolean checked = !mCheckStates.get(position, false); 1096 mCheckStates.put(position, checked); 1097 if (mCheckedIdStates != null && mAdapter.hasStableIds()) { 1098 if (checked) { 1099 mCheckedIdStates.put(mAdapter.getItemId(position), position); 1100 } else { 1101 mCheckedIdStates.delete(mAdapter.getItemId(position)); 1102 } 1103 } 1104 if (checked) { 1105 mCheckedItemCount++; 1106 } else { 1107 mCheckedItemCount--; 1108 } 1109 if (mChoiceActionMode != null) { 1110 mMultiChoiceModeCallback.onItemCheckedStateChanged(mChoiceActionMode, 1111 position, id, checked); 1112 dispatchItemClick = false; 1113 } 1114 checkedStateChanged = true; 1115 } else if (mChoiceMode == CHOICE_MODE_SINGLE) { 1116 boolean checked = !mCheckStates.get(position, false); 1117 if (checked) { 1118 mCheckStates.clear(); 1119 mCheckStates.put(position, true); 1120 if (mCheckedIdStates != null && mAdapter.hasStableIds()) { 1121 mCheckedIdStates.clear(); 1122 mCheckedIdStates.put(mAdapter.getItemId(position), position); 1123 } 1124 mCheckedItemCount = 1; 1125 } else if (mCheckStates.size() == 0 || !mCheckStates.valueAt(0)) { 1126 mCheckedItemCount = 0; 1127 } 1128 checkedStateChanged = true; 1129 } 1130 1131 if (checkedStateChanged) { 1132 updateOnScreenCheckedViews(); 1133 } 1134 } 1135 1136 if (dispatchItemClick) { 1137 handled |= super.performItemClick(view, position, id); 1138 } 1139 1140 return handled; 1141 } 1142 1143 /** 1144 * Perform a quick, in-place update of the checked or activated state 1145 * on all visible item views. This should only be called when a valid 1146 * choice mode is active. 1147 */ 1148 private void updateOnScreenCheckedViews() { 1149 final int firstPos = mFirstPosition; 1150 final int count = getChildCount(); 1151 final boolean useActivated = getContext().getApplicationInfo().targetSdkVersion 1152 >= android.os.Build.VERSION_CODES.HONEYCOMB; 1153 for (int i = 0; i < count; i++) { 1154 final View child = getChildAt(i); 1155 final int position = firstPos + i; 1156 1157 if (child instanceof Checkable) { 1158 ((Checkable) child).setChecked(mCheckStates.get(position)); 1159 } else if (useActivated) { 1160 child.setActivated(mCheckStates.get(position)); 1161 } 1162 } 1163 } 1164 1165 /** 1166 * @see #setChoiceMode(int) 1167 * 1168 * @return The current choice mode 1169 */ 1170 public int getChoiceMode() { 1171 return mChoiceMode; 1172 } 1173 1174 /** 1175 * Defines the choice behavior for the List. By default, Lists do not have any choice behavior 1176 * ({@link #CHOICE_MODE_NONE}). By setting the choiceMode to {@link #CHOICE_MODE_SINGLE}, the 1177 * List allows up to one item to be in a chosen state. By setting the choiceMode to 1178 * {@link #CHOICE_MODE_MULTIPLE}, the list allows any number of items to be chosen. 1179 * 1180 * @param choiceMode One of {@link #CHOICE_MODE_NONE}, {@link #CHOICE_MODE_SINGLE}, or 1181 * {@link #CHOICE_MODE_MULTIPLE} 1182 */ 1183 public void setChoiceMode(int choiceMode) { 1184 mChoiceMode = choiceMode; 1185 if (mChoiceActionMode != null) { 1186 mChoiceActionMode.finish(); 1187 mChoiceActionMode = null; 1188 } 1189 if (mChoiceMode != CHOICE_MODE_NONE) { 1190 if (mCheckStates == null) { 1191 mCheckStates = new SparseBooleanArray(0); 1192 } 1193 if (mCheckedIdStates == null && mAdapter != null && mAdapter.hasStableIds()) { 1194 mCheckedIdStates = new LongSparseArray<Integer>(0); 1195 } 1196 // Modal multi-choice mode only has choices when the mode is active. Clear them. 1197 if (mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL) { 1198 clearChoices(); 1199 setLongClickable(true); 1200 } 1201 } 1202 } 1203 1204 /** 1205 * Set a {@link MultiChoiceModeListener} that will manage the lifecycle of the 1206 * selection {@link ActionMode}. Only used when the choice mode is set to 1207 * {@link #CHOICE_MODE_MULTIPLE_MODAL}. 1208 * 1209 * @param listener Listener that will manage the selection mode 1210 * 1211 * @see #setChoiceMode(int) 1212 */ 1213 public void setMultiChoiceModeListener(MultiChoiceModeListener listener) { 1214 if (mMultiChoiceModeCallback == null) { 1215 mMultiChoiceModeCallback = new MultiChoiceModeWrapper(); 1216 } 1217 mMultiChoiceModeCallback.setWrapped(listener); 1218 } 1219 1220 /** 1221 * @return true if all list content currently fits within the view boundaries 1222 */ 1223 private boolean contentFits() { 1224 final int childCount = getChildCount(); 1225 if (childCount == 0) return true; 1226 if (childCount != mItemCount) return false; 1227 1228 return getChildAt(0).getTop() >= mListPadding.top && 1229 getChildAt(childCount - 1).getBottom() <= getHeight() - mListPadding.bottom; 1230 } 1231 1232 /** 1233 * Specifies whether fast scrolling is enabled or disabled. 1234 * <p> 1235 * When fast scrolling is enabled, the user can quickly scroll through lists 1236 * by dragging the fast scroll thumb. 1237 * <p> 1238 * If the adapter backing this list implements {@link SectionIndexer}, the 1239 * fast scroller will display section header previews as the user scrolls. 1240 * Additionally, the user will be able to quickly jump between sections by 1241 * tapping along the length of the scroll bar. 1242 * 1243 * @see SectionIndexer 1244 * @see #isFastScrollEnabled() 1245 * @param enabled true to enable fast scrolling, false otherwise 1246 */ 1247 public void setFastScrollEnabled(final boolean enabled) { 1248 if (mFastScrollEnabled != enabled) { 1249 mFastScrollEnabled = enabled; 1250 1251 if (isOwnerThread()) { 1252 setFastScrollerEnabledUiThread(enabled); 1253 } else { 1254 post(new Runnable() { 1255 @Override 1256 public void run() { 1257 setFastScrollerEnabledUiThread(enabled); 1258 } 1259 }); 1260 } 1261 } 1262 } 1263 1264 private void setFastScrollerEnabledUiThread(boolean enabled) { 1265 if (mFastScroll != null) { 1266 mFastScroll.setEnabled(enabled); 1267 } else if (enabled) { 1268 mFastScroll = new FastScroller(this, mFastScrollStyle); 1269 mFastScroll.setEnabled(true); 1270 } 1271 1272 resolvePadding(); 1273 1274 if (mFastScroll != null) { 1275 mFastScroll.updateLayout(); 1276 } 1277 } 1278 1279 /** 1280 * Specifies the style of the fast scroller decorations. 1281 * 1282 * @param styleResId style resource containing fast scroller properties 1283 * @see android.R.styleable#FastScroll 1284 */ 1285 public void setFastScrollStyle(int styleResId) { 1286 if (mFastScroll == null) { 1287 mFastScrollStyle = styleResId; 1288 } else { 1289 mFastScroll.setStyle(styleResId); 1290 } 1291 } 1292 1293 /** 1294 * Set whether or not the fast scroller should always be shown in place of 1295 * the standard scroll bars. This will enable fast scrolling if it is not 1296 * already enabled. 1297 * <p> 1298 * Fast scrollers shown in this way will not fade out and will be a 1299 * permanent fixture within the list. This is best combined with an inset 1300 * scroll bar style to ensure the scroll bar does not overlap content. 1301 * 1302 * @param alwaysShow true if the fast scroller should always be displayed, 1303 * false otherwise 1304 * @see #setScrollBarStyle(int) 1305 * @see #setFastScrollEnabled(boolean) 1306 */ 1307 public void setFastScrollAlwaysVisible(final boolean alwaysShow) { 1308 if (mFastScrollAlwaysVisible != alwaysShow) { 1309 if (alwaysShow && !mFastScrollEnabled) { 1310 setFastScrollEnabled(true); 1311 } 1312 1313 mFastScrollAlwaysVisible = alwaysShow; 1314 1315 if (isOwnerThread()) { 1316 setFastScrollerAlwaysVisibleUiThread(alwaysShow); 1317 } else { 1318 post(new Runnable() { 1319 @Override 1320 public void run() { 1321 setFastScrollerAlwaysVisibleUiThread(alwaysShow); 1322 } 1323 }); 1324 } 1325 } 1326 } 1327 1328 private void setFastScrollerAlwaysVisibleUiThread(boolean alwaysShow) { 1329 if (mFastScroll != null) { 1330 mFastScroll.setAlwaysShow(alwaysShow); 1331 } 1332 } 1333 1334 /** 1335 * @return whether the current thread is the one that created the view 1336 */ 1337 private boolean isOwnerThread() { 1338 return mOwnerThread == Thread.currentThread(); 1339 } 1340 1341 /** 1342 * Returns true if the fast scroller is set to always show on this view. 1343 * 1344 * @return true if the fast scroller will always show 1345 * @see #setFastScrollAlwaysVisible(boolean) 1346 */ 1347 public boolean isFastScrollAlwaysVisible() { 1348 if (mFastScroll == null) { 1349 return mFastScrollEnabled && mFastScrollAlwaysVisible; 1350 } else { 1351 return mFastScroll.isEnabled() && mFastScroll.isAlwaysShowEnabled(); 1352 } 1353 } 1354 1355 @Override 1356 public int getVerticalScrollbarWidth() { 1357 if (mFastScroll != null && mFastScroll.isEnabled()) { 1358 return Math.max(super.getVerticalScrollbarWidth(), mFastScroll.getWidth()); 1359 } 1360 return super.getVerticalScrollbarWidth(); 1361 } 1362 1363 /** 1364 * Returns true if the fast scroller is enabled. 1365 * 1366 * @see #setFastScrollEnabled(boolean) 1367 * @return true if fast scroll is enabled, false otherwise 1368 */ 1369 @ViewDebug.ExportedProperty 1370 public boolean isFastScrollEnabled() { 1371 if (mFastScroll == null) { 1372 return mFastScrollEnabled; 1373 } else { 1374 return mFastScroll.isEnabled(); 1375 } 1376 } 1377 1378 @Override 1379 public void setVerticalScrollbarPosition(int position) { 1380 super.setVerticalScrollbarPosition(position); 1381 if (mFastScroll != null) { 1382 mFastScroll.setScrollbarPosition(position); 1383 } 1384 } 1385 1386 @Override 1387 public void setScrollBarStyle(int style) { 1388 super.setScrollBarStyle(style); 1389 if (mFastScroll != null) { 1390 mFastScroll.setScrollBarStyle(style); 1391 } 1392 } 1393 1394 /** 1395 * If fast scroll is enabled, then don't draw the vertical scrollbar. 1396 * @hide 1397 */ 1398 @Override 1399 protected boolean isVerticalScrollBarHidden() { 1400 return isFastScrollEnabled(); 1401 } 1402 1403 /** 1404 * When smooth scrollbar is enabled, the position and size of the scrollbar thumb 1405 * is computed based on the number of visible pixels in the visible items. This 1406 * however assumes that all list items have the same height. If you use a list in 1407 * which items have different heights, the scrollbar will change appearance as the 1408 * user scrolls through the list. To avoid this issue, you need to disable this 1409 * property. 1410 * 1411 * When smooth scrollbar is disabled, the position and size of the scrollbar thumb 1412 * is based solely on the number of items in the adapter and the position of the 1413 * visible items inside the adapter. This provides a stable scrollbar as the user 1414 * navigates through a list of items with varying heights. 1415 * 1416 * @param enabled Whether or not to enable smooth scrollbar. 1417 * 1418 * @see #setSmoothScrollbarEnabled(boolean) 1419 * @attr ref android.R.styleable#AbsListView_smoothScrollbar 1420 */ 1421 public void setSmoothScrollbarEnabled(boolean enabled) { 1422 mSmoothScrollbarEnabled = enabled; 1423 } 1424 1425 /** 1426 * Returns the current state of the fast scroll feature. 1427 * 1428 * @return True if smooth scrollbar is enabled is enabled, false otherwise. 1429 * 1430 * @see #setSmoothScrollbarEnabled(boolean) 1431 */ 1432 @ViewDebug.ExportedProperty 1433 public boolean isSmoothScrollbarEnabled() { 1434 return mSmoothScrollbarEnabled; 1435 } 1436 1437 /** 1438 * Set the listener that will receive notifications every time the list scrolls. 1439 * 1440 * @param l the scroll listener 1441 */ 1442 public void setOnScrollListener(OnScrollListener l) { 1443 mOnScrollListener = l; 1444 invokeOnItemScrollListener(); 1445 } 1446 1447 /** 1448 * Notify our scroll listener (if there is one) of a change in scroll state 1449 */ 1450 void invokeOnItemScrollListener() { 1451 if (mFastScroll != null) { 1452 mFastScroll.onScroll(mFirstPosition, getChildCount(), mItemCount); 1453 } 1454 if (mOnScrollListener != null) { 1455 mOnScrollListener.onScroll(this, mFirstPosition, getChildCount(), mItemCount); 1456 } 1457 onScrollChanged(0, 0, 0, 0); // dummy values, View's implementation does not use these. 1458 } 1459 1460 @Override 1461 public void sendAccessibilityEvent(int eventType) { 1462 // Since this class calls onScrollChanged even if the mFirstPosition and the 1463 // child count have not changed we will avoid sending duplicate accessibility 1464 // events. 1465 if (eventType == AccessibilityEvent.TYPE_VIEW_SCROLLED) { 1466 final int firstVisiblePosition = getFirstVisiblePosition(); 1467 final int lastVisiblePosition = getLastVisiblePosition(); 1468 if (mLastAccessibilityScrollEventFromIndex == firstVisiblePosition 1469 && mLastAccessibilityScrollEventToIndex == lastVisiblePosition) { 1470 return; 1471 } else { 1472 mLastAccessibilityScrollEventFromIndex = firstVisiblePosition; 1473 mLastAccessibilityScrollEventToIndex = lastVisiblePosition; 1474 } 1475 } 1476 super.sendAccessibilityEvent(eventType); 1477 } 1478 1479 @Override 1480 public void onInitializeAccessibilityEvent(AccessibilityEvent event) { 1481 super.onInitializeAccessibilityEvent(event); 1482 event.setClassName(AbsListView.class.getName()); 1483 } 1484 1485 @Override 1486 public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) { 1487 super.onInitializeAccessibilityNodeInfo(info); 1488 info.setClassName(AbsListView.class.getName()); 1489 if (isEnabled()) { 1490 if (canScrollUp()) { 1491 info.addAction(AccessibilityNodeInfo.ACTION_SCROLL_BACKWARD); 1492 info.setScrollable(true); 1493 } 1494 if (canScrollDown()) { 1495 info.addAction(AccessibilityNodeInfo.ACTION_SCROLL_FORWARD); 1496 info.setScrollable(true); 1497 } 1498 } 1499 } 1500 1501 int getSelectionModeForAccessibility() { 1502 final int choiceMode = getChoiceMode(); 1503 switch (choiceMode) { 1504 case CHOICE_MODE_NONE: 1505 return CollectionInfo.SELECTION_MODE_NONE; 1506 case CHOICE_MODE_SINGLE: 1507 return CollectionInfo.SELECTION_MODE_SINGLE; 1508 case CHOICE_MODE_MULTIPLE: 1509 case CHOICE_MODE_MULTIPLE_MODAL: 1510 return CollectionInfo.SELECTION_MODE_MULTIPLE; 1511 default: 1512 return CollectionInfo.SELECTION_MODE_NONE; 1513 } 1514 } 1515 1516 @Override 1517 public boolean performAccessibilityAction(int action, Bundle arguments) { 1518 if (super.performAccessibilityAction(action, arguments)) { 1519 return true; 1520 } 1521 switch (action) { 1522 case AccessibilityNodeInfo.ACTION_SCROLL_FORWARD: { 1523 if (isEnabled() && getLastVisiblePosition() < getCount() - 1) { 1524 final int viewportHeight = getHeight() - mListPadding.top - mListPadding.bottom; 1525 smoothScrollBy(viewportHeight, PositionScroller.SCROLL_DURATION); 1526 return true; 1527 } 1528 } return false; 1529 case AccessibilityNodeInfo.ACTION_SCROLL_BACKWARD: { 1530 if (isEnabled() && mFirstPosition > 0) { 1531 final int viewportHeight = getHeight() - mListPadding.top - mListPadding.bottom; 1532 smoothScrollBy(-viewportHeight, PositionScroller.SCROLL_DURATION); 1533 return true; 1534 } 1535 } return false; 1536 } 1537 return false; 1538 } 1539 1540 /** @hide */ 1541 @Override 1542 public View findViewByAccessibilityIdTraversal(int accessibilityId) { 1543 if (accessibilityId == getAccessibilityViewId()) { 1544 return this; 1545 } 1546 // If the data changed the children are invalid since the data model changed. 1547 // Hence, we pretend they do not exist. After a layout the children will sync 1548 // with the model at which point we notify that the accessibility state changed, 1549 // so a service will be able to re-fetch the views. 1550 if (mDataChanged) { 1551 return null; 1552 } 1553 return super.findViewByAccessibilityIdTraversal(accessibilityId); 1554 } 1555 1556 /** 1557 * Indicates whether the children's drawing cache is used during a scroll. 1558 * By default, the drawing cache is enabled but this will consume more memory. 1559 * 1560 * @return true if the scrolling cache is enabled, false otherwise 1561 * 1562 * @see #setScrollingCacheEnabled(boolean) 1563 * @see View#setDrawingCacheEnabled(boolean) 1564 */ 1565 @ViewDebug.ExportedProperty 1566 public boolean isScrollingCacheEnabled() { 1567 return mScrollingCacheEnabled; 1568 } 1569 1570 /** 1571 * Enables or disables the children's drawing cache during a scroll. 1572 * By default, the drawing cache is enabled but this will use more memory. 1573 * 1574 * When the scrolling cache is enabled, the caches are kept after the 1575 * first scrolling. You can manually clear the cache by calling 1576 * {@link android.view.ViewGroup#setChildrenDrawingCacheEnabled(boolean)}. 1577 * 1578 * @param enabled true to enable the scroll cache, false otherwise 1579 * 1580 * @see #isScrollingCacheEnabled() 1581 * @see View#setDrawingCacheEnabled(boolean) 1582 */ 1583 public void setScrollingCacheEnabled(boolean enabled) { 1584 if (mScrollingCacheEnabled && !enabled) { 1585 clearScrollingCache(); 1586 } 1587 mScrollingCacheEnabled = enabled; 1588 } 1589 1590 /** 1591 * Enables or disables the type filter window. If enabled, typing when 1592 * this view has focus will filter the children to match the users input. 1593 * Note that the {@link Adapter} used by this view must implement the 1594 * {@link Filterable} interface. 1595 * 1596 * @param textFilterEnabled true to enable type filtering, false otherwise 1597 * 1598 * @see Filterable 1599 */ 1600 public void setTextFilterEnabled(boolean textFilterEnabled) { 1601 mTextFilterEnabled = textFilterEnabled; 1602 } 1603 1604 /** 1605 * Indicates whether type filtering is enabled for this view 1606 * 1607 * @return true if type filtering is enabled, false otherwise 1608 * 1609 * @see #setTextFilterEnabled(boolean) 1610 * @see Filterable 1611 */ 1612 @ViewDebug.ExportedProperty 1613 public boolean isTextFilterEnabled() { 1614 return mTextFilterEnabled; 1615 } 1616 1617 @Override 1618 public void getFocusedRect(Rect r) { 1619 View view = getSelectedView(); 1620 if (view != null && view.getParent() == this) { 1621 // the focused rectangle of the selected view offset into the 1622 // coordinate space of this view. 1623 view.getFocusedRect(r); 1624 offsetDescendantRectToMyCoords(view, r); 1625 } else { 1626 // otherwise, just the norm 1627 super.getFocusedRect(r); 1628 } 1629 } 1630 1631 private void useDefaultSelector() { 1632 setSelector(getContext().getDrawable( 1633 com.android.internal.R.drawable.list_selector_background)); 1634 } 1635 1636 /** 1637 * Indicates whether the content of this view is pinned to, or stacked from, 1638 * the bottom edge. 1639 * 1640 * @return true if the content is stacked from the bottom edge, false otherwise 1641 */ 1642 @ViewDebug.ExportedProperty 1643 public boolean isStackFromBottom() { 1644 return mStackFromBottom; 1645 } 1646 1647 /** 1648 * When stack from bottom is set to true, the list fills its content starting from 1649 * the bottom of the view. 1650 * 1651 * @param stackFromBottom true to pin the view's content to the bottom edge, 1652 * false to pin the view's content to the top edge 1653 */ 1654 public void setStackFromBottom(boolean stackFromBottom) { 1655 if (mStackFromBottom != stackFromBottom) { 1656 mStackFromBottom = stackFromBottom; 1657 requestLayoutIfNecessary(); 1658 } 1659 } 1660 1661 void requestLayoutIfNecessary() { 1662 if (getChildCount() > 0) { 1663 resetList(); 1664 requestLayout(); 1665 invalidate(); 1666 } 1667 } 1668 1669 static class SavedState extends BaseSavedState { 1670 long selectedId; 1671 long firstId; 1672 int viewTop; 1673 int position; 1674 int height; 1675 String filter; 1676 boolean inActionMode; 1677 int checkedItemCount; 1678 SparseBooleanArray checkState; 1679 LongSparseArray<Integer> checkIdState; 1680 1681 /** 1682 * Constructor called from {@link AbsListView#onSaveInstanceState()} 1683 */ 1684 SavedState(Parcelable superState) { 1685 super(superState); 1686 } 1687 1688 /** 1689 * Constructor called from {@link #CREATOR} 1690 */ 1691 private SavedState(Parcel in) { 1692 super(in); 1693 selectedId = in.readLong(); 1694 firstId = in.readLong(); 1695 viewTop = in.readInt(); 1696 position = in.readInt(); 1697 height = in.readInt(); 1698 filter = in.readString(); 1699 inActionMode = in.readByte() != 0; 1700 checkedItemCount = in.readInt(); 1701 checkState = in.readSparseBooleanArray(); 1702 final int N = in.readInt(); 1703 if (N > 0) { 1704 checkIdState = new LongSparseArray<Integer>(); 1705 for (int i=0; i<N; i++) { 1706 final long key = in.readLong(); 1707 final int value = in.readInt(); 1708 checkIdState.put(key, value); 1709 } 1710 } 1711 } 1712 1713 @Override 1714 public void writeToParcel(Parcel out, int flags) { 1715 super.writeToParcel(out, flags); 1716 out.writeLong(selectedId); 1717 out.writeLong(firstId); 1718 out.writeInt(viewTop); 1719 out.writeInt(position); 1720 out.writeInt(height); 1721 out.writeString(filter); 1722 out.writeByte((byte) (inActionMode ? 1 : 0)); 1723 out.writeInt(checkedItemCount); 1724 out.writeSparseBooleanArray(checkState); 1725 final int N = checkIdState != null ? checkIdState.size() : 0; 1726 out.writeInt(N); 1727 for (int i=0; i<N; i++) { 1728 out.writeLong(checkIdState.keyAt(i)); 1729 out.writeInt(checkIdState.valueAt(i)); 1730 } 1731 } 1732 1733 @Override 1734 public String toString() { 1735 return "AbsListView.SavedState{" 1736 + Integer.toHexString(System.identityHashCode(this)) 1737 + " selectedId=" + selectedId 1738 + " firstId=" + firstId 1739 + " viewTop=" + viewTop 1740 + " position=" + position 1741 + " height=" + height 1742 + " filter=" + filter 1743 + " checkState=" + checkState + "}"; 1744 } 1745 1746 public static final Parcelable.Creator<SavedState> CREATOR 1747 = new Parcelable.Creator<SavedState>() { 1748 @Override 1749 public SavedState createFromParcel(Parcel in) { 1750 return new SavedState(in); 1751 } 1752 1753 @Override 1754 public SavedState[] newArray(int size) { 1755 return new SavedState[size]; 1756 } 1757 }; 1758 } 1759 1760 @Override 1761 public Parcelable onSaveInstanceState() { 1762 /* 1763 * This doesn't really make sense as the place to dismiss the 1764 * popups, but there don't seem to be any other useful hooks 1765 * that happen early enough to keep from getting complaints 1766 * about having leaked the window. 1767 */ 1768 dismissPopup(); 1769 1770 Parcelable superState = super.onSaveInstanceState(); 1771 1772 SavedState ss = new SavedState(superState); 1773 1774 if (mPendingSync != null) { 1775 // Just keep what we last restored. 1776 ss.selectedId = mPendingSync.selectedId; 1777 ss.firstId = mPendingSync.firstId; 1778 ss.viewTop = mPendingSync.viewTop; 1779 ss.position = mPendingSync.position; 1780 ss.height = mPendingSync.height; 1781 ss.filter = mPendingSync.filter; 1782 ss.inActionMode = mPendingSync.inActionMode; 1783 ss.checkedItemCount = mPendingSync.checkedItemCount; 1784 ss.checkState = mPendingSync.checkState; 1785 ss.checkIdState = mPendingSync.checkIdState; 1786 return ss; 1787 } 1788 1789 boolean haveChildren = getChildCount() > 0 && mItemCount > 0; 1790 long selectedId = getSelectedItemId(); 1791 ss.selectedId = selectedId; 1792 ss.height = getHeight(); 1793 1794 if (selectedId >= 0) { 1795 // Remember the selection 1796 ss.viewTop = mSelectedTop; 1797 ss.position = getSelectedItemPosition(); 1798 ss.firstId = INVALID_POSITION; 1799 } else { 1800 if (haveChildren && mFirstPosition > 0) { 1801 // Remember the position of the first child. 1802 // We only do this if we are not currently at the top of 1803 // the list, for two reasons: 1804 // (1) The list may be in the process of becoming empty, in 1805 // which case mItemCount may not be 0, but if we try to 1806 // ask for any information about position 0 we will crash. 1807 // (2) Being "at the top" seems like a special case, anyway, 1808 // and the user wouldn't expect to end up somewhere else when 1809 // they revisit the list even if its content has changed. 1810 View v = getChildAt(0); 1811 ss.viewTop = v.getTop(); 1812 int firstPos = mFirstPosition; 1813 if (firstPos >= mItemCount) { 1814 firstPos = mItemCount - 1; 1815 } 1816 ss.position = firstPos; 1817 ss.firstId = mAdapter.getItemId(firstPos); 1818 } else { 1819 ss.viewTop = 0; 1820 ss.firstId = INVALID_POSITION; 1821 ss.position = 0; 1822 } 1823 } 1824 1825 ss.filter = null; 1826 if (mFiltered) { 1827 final EditText textFilter = mTextFilter; 1828 if (textFilter != null) { 1829 Editable filterText = textFilter.getText(); 1830 if (filterText != null) { 1831 ss.filter = filterText.toString(); 1832 } 1833 } 1834 } 1835 1836 ss.inActionMode = mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL && mChoiceActionMode != null; 1837 1838 if (mCheckStates != null) { 1839 ss.checkState = mCheckStates.clone(); 1840 } 1841 if (mCheckedIdStates != null) { 1842 final LongSparseArray<Integer> idState = new LongSparseArray<Integer>(); 1843 final int count = mCheckedIdStates.size(); 1844 for (int i = 0; i < count; i++) { 1845 idState.put(mCheckedIdStates.keyAt(i), mCheckedIdStates.valueAt(i)); 1846 } 1847 ss.checkIdState = idState; 1848 } 1849 ss.checkedItemCount = mCheckedItemCount; 1850 1851 if (mRemoteAdapter != null) { 1852 mRemoteAdapter.saveRemoteViewsCache(); 1853 } 1854 1855 return ss; 1856 } 1857 1858 @Override 1859 public void onRestoreInstanceState(Parcelable state) { 1860 SavedState ss = (SavedState) state; 1861 1862 super.onRestoreInstanceState(ss.getSuperState()); 1863 mDataChanged = true; 1864 1865 mSyncHeight = ss.height; 1866 1867 if (ss.selectedId >= 0) { 1868 mNeedSync = true; 1869 mPendingSync = ss; 1870 mSyncRowId = ss.selectedId; 1871 mSyncPosition = ss.position; 1872 mSpecificTop = ss.viewTop; 1873 mSyncMode = SYNC_SELECTED_POSITION; 1874 } else if (ss.firstId >= 0) { 1875 setSelectedPositionInt(INVALID_POSITION); 1876 // Do this before setting mNeedSync since setNextSelectedPosition looks at mNeedSync 1877 setNextSelectedPositionInt(INVALID_POSITION); 1878 mSelectorPosition = INVALID_POSITION; 1879 mNeedSync = true; 1880 mPendingSync = ss; 1881 mSyncRowId = ss.firstId; 1882 mSyncPosition = ss.position; 1883 mSpecificTop = ss.viewTop; 1884 mSyncMode = SYNC_FIRST_POSITION; 1885 } 1886 1887 setFilterText(ss.filter); 1888 1889 if (ss.checkState != null) { 1890 mCheckStates = ss.checkState; 1891 } 1892 1893 if (ss.checkIdState != null) { 1894 mCheckedIdStates = ss.checkIdState; 1895 } 1896 1897 mCheckedItemCount = ss.checkedItemCount; 1898 1899 if (ss.inActionMode && mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL && 1900 mMultiChoiceModeCallback != null) { 1901 mChoiceActionMode = startActionMode(mMultiChoiceModeCallback); 1902 } 1903 1904 requestLayout(); 1905 } 1906 1907 private boolean acceptFilter() { 1908 return mTextFilterEnabled && getAdapter() instanceof Filterable && 1909 ((Filterable) getAdapter()).getFilter() != null; 1910 } 1911 1912 /** 1913 * Sets the initial value for the text filter. 1914 * @param filterText The text to use for the filter. 1915 * 1916 * @see #setTextFilterEnabled 1917 */ 1918 public void setFilterText(String filterText) { 1919 // TODO: Should we check for acceptFilter()? 1920 if (mTextFilterEnabled && !TextUtils.isEmpty(filterText)) { 1921 createTextFilter(false); 1922 // This is going to call our listener onTextChanged, but we might not 1923 // be ready to bring up a window yet 1924 mTextFilter.setText(filterText); 1925 mTextFilter.setSelection(filterText.length()); 1926 if (mAdapter instanceof Filterable) { 1927 // if mPopup is non-null, then onTextChanged will do the filtering 1928 if (mPopup == null) { 1929 Filter f = ((Filterable) mAdapter).getFilter(); 1930 f.filter(filterText); 1931 } 1932 // Set filtered to true so we will display the filter window when our main 1933 // window is ready 1934 mFiltered = true; 1935 mDataSetObserver.clearSavedState(); 1936 } 1937 } 1938 } 1939 1940 /** 1941 * Returns the list's text filter, if available. 1942 * @return the list's text filter or null if filtering isn't enabled 1943 */ 1944 public CharSequence getTextFilter() { 1945 if (mTextFilterEnabled && mTextFilter != null) { 1946 return mTextFilter.getText(); 1947 } 1948 return null; 1949 } 1950 1951 @Override 1952 protected void onFocusChanged(boolean gainFocus, int direction, Rect previouslyFocusedRect) { 1953 super.onFocusChanged(gainFocus, direction, previouslyFocusedRect); 1954 if (gainFocus && mSelectedPosition < 0 && !isInTouchMode()) { 1955 if (!isAttachedToWindow() && mAdapter != null) { 1956 // Data may have changed while we were detached and it's valid 1957 // to change focus while detached. Refresh so we don't die. 1958 mDataChanged = true; 1959 mOldItemCount = mItemCount; 1960 mItemCount = mAdapter.getCount(); 1961 } 1962 resurrectSelection(); 1963 } 1964 } 1965 1966 @Override 1967 public void requestLayout() { 1968 if (!mBlockLayoutRequests && !mInLayout) { 1969 super.requestLayout(); 1970 } 1971 } 1972 1973 /** 1974 * The list is empty. Clear everything out. 1975 */ 1976 void resetList() { 1977 removeAllViewsInLayout(); 1978 mFirstPosition = 0; 1979 mDataChanged = false; 1980 mPositionScrollAfterLayout = null; 1981 mNeedSync = false; 1982 mPendingSync = null; 1983 mOldSelectedPosition = INVALID_POSITION; 1984 mOldSelectedRowId = INVALID_ROW_ID; 1985 setSelectedPositionInt(INVALID_POSITION); 1986 setNextSelectedPositionInt(INVALID_POSITION); 1987 mSelectedTop = 0; 1988 mSelectorPosition = INVALID_POSITION; 1989 mSelectorRect.setEmpty(); 1990 invalidate(); 1991 } 1992 1993 @Override 1994 protected int computeVerticalScrollExtent() { 1995 final int count = getChildCount(); 1996 if (count > 0) { 1997 if (mSmoothScrollbarEnabled) { 1998 int extent = count * 100; 1999 2000 View view = getChildAt(0); 2001 final int top = view.getTop(); 2002 int height = view.getHeight(); 2003 if (height > 0) { 2004 extent += (top * 100) / height; 2005 } 2006 2007 view = getChildAt(count - 1); 2008 final int bottom = view.getBottom(); 2009 height = view.getHeight(); 2010 if (height > 0) { 2011 extent -= ((bottom - getHeight()) * 100) / height; 2012 } 2013 2014 return extent; 2015 } else { 2016 return 1; 2017 } 2018 } 2019 return 0; 2020 } 2021 2022 @Override 2023 protected int computeVerticalScrollOffset() { 2024 final int firstPosition = mFirstPosition; 2025 final int childCount = getChildCount(); 2026 if (firstPosition >= 0 && childCount > 0) { 2027 if (mSmoothScrollbarEnabled) { 2028 final View view = getChildAt(0); 2029 final int top = view.getTop(); 2030 int height = view.getHeight(); 2031 if (height > 0) { 2032 return Math.max(firstPosition * 100 - (top * 100) / height + 2033 (int)((float)mScrollY / getHeight() * mItemCount * 100), 0); 2034 } 2035 } else { 2036 int index; 2037 final int count = mItemCount; 2038 if (firstPosition == 0) { 2039 index = 0; 2040 } else if (firstPosition + childCount == count) { 2041 index = count; 2042 } else { 2043 index = firstPosition + childCount / 2; 2044 } 2045 return (int) (firstPosition + childCount * (index / (float) count)); 2046 } 2047 } 2048 return 0; 2049 } 2050 2051 @Override 2052 protected int computeVerticalScrollRange() { 2053 int result; 2054 if (mSmoothScrollbarEnabled) { 2055 result = Math.max(mItemCount * 100, 0); 2056 if (mScrollY != 0) { 2057 // Compensate for overscroll 2058 result += Math.abs((int) ((float) mScrollY / getHeight() * mItemCount * 100)); 2059 } 2060 } else { 2061 result = mItemCount; 2062 } 2063 return result; 2064 } 2065 2066 @Override 2067 protected float getTopFadingEdgeStrength() { 2068 final int count = getChildCount(); 2069 final float fadeEdge = super.getTopFadingEdgeStrength(); 2070 if (count == 0) { 2071 return fadeEdge; 2072 } else { 2073 if (mFirstPosition > 0) { 2074 return 1.0f; 2075 } 2076 2077 final int top = getChildAt(0).getTop(); 2078 final float fadeLength = getVerticalFadingEdgeLength(); 2079 return top < mPaddingTop ? -(top - mPaddingTop) / fadeLength : fadeEdge; 2080 } 2081 } 2082 2083 @Override 2084 protected float getBottomFadingEdgeStrength() { 2085 final int count = getChildCount(); 2086 final float fadeEdge = super.getBottomFadingEdgeStrength(); 2087 if (count == 0) { 2088 return fadeEdge; 2089 } else { 2090 if (mFirstPosition + count - 1 < mItemCount - 1) { 2091 return 1.0f; 2092 } 2093 2094 final int bottom = getChildAt(count - 1).getBottom(); 2095 final int height = getHeight(); 2096 final float fadeLength = getVerticalFadingEdgeLength(); 2097 return bottom > height - mPaddingBottom ? 2098 (bottom - height + mPaddingBottom) / fadeLength : fadeEdge; 2099 } 2100 } 2101 2102 @Override 2103 protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { 2104 if (mSelector == null) { 2105 useDefaultSelector(); 2106 } 2107 final Rect listPadding = mListPadding; 2108 listPadding.left = mSelectionLeftPadding + mPaddingLeft; 2109 listPadding.top = mSelectionTopPadding + mPaddingTop; 2110 listPadding.right = mSelectionRightPadding + mPaddingRight; 2111 listPadding.bottom = mSelectionBottomPadding + mPaddingBottom; 2112 2113 // Check if our previous measured size was at a point where we should scroll later. 2114 if (mTranscriptMode == TRANSCRIPT_MODE_NORMAL) { 2115 final int childCount = getChildCount(); 2116 final int listBottom = getHeight() - getPaddingBottom(); 2117 final View lastChild = getChildAt(childCount - 1); 2118 final int lastBottom = lastChild != null ? lastChild.getBottom() : listBottom; 2119 mForceTranscriptScroll = mFirstPosition + childCount >= mLastHandledItemCount && 2120 lastBottom <= listBottom; 2121 } 2122 } 2123 2124 /** 2125 * Subclasses should NOT override this method but 2126 * {@link #layoutChildren()} instead. 2127 */ 2128 @Override 2129 protected void onLayout(boolean changed, int l, int t, int r, int b) { 2130 super.onLayout(changed, l, t, r, b); 2131 2132 mInLayout = true; 2133 2134 final int childCount = getChildCount(); 2135 if (changed) { 2136 for (int i = 0; i < childCount; i++) { 2137 getChildAt(i).forceLayout(); 2138 } 2139 mRecycler.markChildrenDirty(); 2140 } 2141 2142 layoutChildren(); 2143 mInLayout = false; 2144 2145 mOverscrollMax = (b - t) / OVERSCROLL_LIMIT_DIVISOR; 2146 2147 // TODO: Move somewhere sane. This doesn't belong in onLayout(). 2148 if (mFastScroll != null) { 2149 mFastScroll.onItemCountChanged(getChildCount(), mItemCount); 2150 } 2151 } 2152 2153 /** 2154 * @hide 2155 */ 2156 @Override 2157 protected boolean setFrame(int left, int top, int right, int bottom) { 2158 final boolean changed = super.setFrame(left, top, right, bottom); 2159 2160 if (changed) { 2161 // Reposition the popup when the frame has changed. This includes 2162 // translating the widget, not just changing its dimension. The 2163 // filter popup needs to follow the widget. 2164 final boolean visible = getWindowVisibility() == View.VISIBLE; 2165 if (mFiltered && visible && mPopup != null && mPopup.isShowing()) { 2166 positionPopup(); 2167 } 2168 } 2169 2170 return changed; 2171 } 2172 2173 /** 2174 * Subclasses must override this method to layout their children. 2175 */ 2176 protected void layoutChildren() { 2177 } 2178 2179 /** 2180 * @param focusedView view that holds accessibility focus 2181 * @return direct child that contains accessibility focus, or null if no 2182 * child contains accessibility focus 2183 */ 2184 View getAccessibilityFocusedChild(View focusedView) { 2185 ViewParent viewParent = focusedView.getParent(); 2186 while ((viewParent instanceof View) && (viewParent != this)) { 2187 focusedView = (View) viewParent; 2188 viewParent = viewParent.getParent(); 2189 } 2190 2191 if (!(viewParent instanceof View)) { 2192 return null; 2193 } 2194 2195 return focusedView; 2196 } 2197 2198 void updateScrollIndicators() { 2199 if (mScrollUp != null) { 2200 mScrollUp.setVisibility(canScrollUp() ? View.VISIBLE : View.INVISIBLE); 2201 } 2202 2203 if (mScrollDown != null) { 2204 mScrollDown.setVisibility(canScrollDown() ? View.VISIBLE : View.INVISIBLE); 2205 } 2206 } 2207 2208 private boolean canScrollUp() { 2209 boolean canScrollUp; 2210 // 0th element is not visible 2211 canScrollUp = mFirstPosition > 0; 2212 2213 // ... Or top of 0th element is not visible 2214 if (!canScrollUp) { 2215 if (getChildCount() > 0) { 2216 View child = getChildAt(0); 2217 canScrollUp = child.getTop() < mListPadding.top; 2218 } 2219 } 2220 2221 return canScrollUp; 2222 } 2223 2224 private boolean canScrollDown() { 2225 boolean canScrollDown; 2226 int count = getChildCount(); 2227 2228 // Last item is not visible 2229 canScrollDown = (mFirstPosition + count) < mItemCount; 2230 2231 // ... Or bottom of the last element is not visible 2232 if (!canScrollDown && count > 0) { 2233 View child = getChildAt(count - 1); 2234 canScrollDown = child.getBottom() > mBottom - mListPadding.bottom; 2235 } 2236 2237 return canScrollDown; 2238 } 2239 2240 @Override 2241 @ViewDebug.ExportedProperty 2242 public View getSelectedView() { 2243 if (mItemCount > 0 && mSelectedPosition >= 0) { 2244 return getChildAt(mSelectedPosition - mFirstPosition); 2245 } else { 2246 return null; 2247 } 2248 } 2249 2250 /** 2251 * List padding is the maximum of the normal view's padding and the padding of the selector. 2252 * 2253 * @see android.view.View#getPaddingTop() 2254 * @see #getSelector() 2255 * 2256 * @return The top list padding. 2257 */ 2258 public int getListPaddingTop() { 2259 return mListPadding.top; 2260 } 2261 2262 /** 2263 * List padding is the maximum of the normal view's padding and the padding of the selector. 2264 * 2265 * @see android.view.View#getPaddingBottom() 2266 * @see #getSelector() 2267 * 2268 * @return The bottom list padding. 2269 */ 2270 public int getListPaddingBottom() { 2271 return mListPadding.bottom; 2272 } 2273 2274 /** 2275 * List padding is the maximum of the normal view's padding and the padding of the selector. 2276 * 2277 * @see android.view.View#getPaddingLeft() 2278 * @see #getSelector() 2279 * 2280 * @return The left list padding. 2281 */ 2282 public int getListPaddingLeft() { 2283 return mListPadding.left; 2284 } 2285 2286 /** 2287 * List padding is the maximum of the normal view's padding and the padding of the selector. 2288 * 2289 * @see android.view.View#getPaddingRight() 2290 * @see #getSelector() 2291 * 2292 * @return The right list padding. 2293 */ 2294 public int getListPaddingRight() { 2295 return mListPadding.right; 2296 } 2297 2298 /** 2299 * Get a view and have it show the data associated with the specified 2300 * position. This is called when we have already discovered that the view is 2301 * not available for reuse in the recycle bin. The only choices left are 2302 * converting an old view or making a new one. 2303 * 2304 * @param position The position to display 2305 * @param isScrap Array of at least 1 boolean, the first entry will become true if 2306 * the returned view was taken from the scrap heap, false if otherwise. 2307 * 2308 * @return A view displaying the data associated with the specified position 2309 */ 2310 View obtainView(int position, boolean[] isScrap) { 2311 Trace.traceBegin(Trace.TRACE_TAG_VIEW, "obtainView"); 2312 2313 isScrap[0] = false; 2314 2315 // Check whether we have a transient state view. Attempt to re-bind the 2316 // data and discard the view if we fail. 2317 final View transientView = mRecycler.getTransientStateView(position); 2318 if (transientView != null) { 2319 final LayoutParams params = (LayoutParams) transientView.getLayoutParams(); 2320 2321 // If the view type hasn't changed, attempt to re-bind the data. 2322 if (params.viewType == mAdapter.getItemViewType(position)) { 2323 final View updatedView = mAdapter.getView(position, transientView, this); 2324 2325 // If we failed to re-bind the data, scrap the obtained view. 2326 if (updatedView != transientView) { 2327 setItemViewLayoutParams(updatedView, position); 2328 mRecycler.addScrapView(updatedView, position); 2329 } 2330 } 2331 2332 // Scrap view implies temporary detachment. 2333 isScrap[0] = true; 2334 return transientView; 2335 } 2336 2337 final View scrapView = mRecycler.getScrapView(position); 2338 final View child = mAdapter.getView(position, scrapView, this); 2339 if (scrapView != null) { 2340 if (child != scrapView) { 2341 // Failed to re-bind the data, return scrap to the heap. 2342 mRecycler.addScrapView(scrapView, position); 2343 } else { 2344 isScrap[0] = true; 2345 2346 child.dispatchFinishTemporaryDetach(); 2347 } 2348 } 2349 2350 if (mCacheColorHint != 0) { 2351 child.setDrawingCacheBackgroundColor(mCacheColorHint); 2352 } 2353 2354 if (child.getImportantForAccessibility() == IMPORTANT_FOR_ACCESSIBILITY_AUTO) { 2355 child.setImportantForAccessibility(IMPORTANT_FOR_ACCESSIBILITY_YES); 2356 } 2357 2358 setItemViewLayoutParams(child, position); 2359 2360 if (AccessibilityManager.getInstance(mContext).isEnabled()) { 2361 if (mAccessibilityDelegate == null) { 2362 mAccessibilityDelegate = new ListItemAccessibilityDelegate(); 2363 } 2364 if (child.getAccessibilityDelegate() == null) { 2365 child.setAccessibilityDelegate(mAccessibilityDelegate); 2366 } 2367 } 2368 2369 Trace.traceEnd(Trace.TRACE_TAG_VIEW); 2370 2371 return child; 2372 } 2373 2374 private void setItemViewLayoutParams(View child, int position) { 2375 final ViewGroup.LayoutParams vlp = child.getLayoutParams(); 2376 LayoutParams lp; 2377 if (vlp == null) { 2378 lp = (LayoutParams) generateDefaultLayoutParams(); 2379 } else if (!checkLayoutParams(vlp)) { 2380 lp = (LayoutParams) generateLayoutParams(vlp); 2381 } else { 2382 lp = (LayoutParams) vlp; 2383 } 2384 2385 if (mAdapterHasStableIds) { 2386 lp.itemId = mAdapter.getItemId(position); 2387 } 2388 lp.viewType = mAdapter.getItemViewType(position); 2389 child.setLayoutParams(lp); 2390 } 2391 2392 class ListItemAccessibilityDelegate extends AccessibilityDelegate { 2393 @Override 2394 public AccessibilityNodeInfo createAccessibilityNodeInfo(View host) { 2395 // If the data changed the children are invalid since the data model changed. 2396 // Hence, we pretend they do not exist. After a layout the children will sync 2397 // with the model at which point we notify that the accessibility state changed, 2398 // so a service will be able to re-fetch the views. 2399 if (mDataChanged) { 2400 return null; 2401 } 2402 return super.createAccessibilityNodeInfo(host); 2403 } 2404 2405 @Override 2406 public void onInitializeAccessibilityNodeInfo(View host, AccessibilityNodeInfo info) { 2407 super.onInitializeAccessibilityNodeInfo(host, info); 2408 2409 final int position = getPositionForView(host); 2410 onInitializeAccessibilityNodeInfoForItem(host, position, info); 2411 } 2412 2413 @Override 2414 public boolean performAccessibilityAction(View host, int action, Bundle arguments) { 2415 if (super.performAccessibilityAction(host, action, arguments)) { 2416 return true; 2417 } 2418 2419 final int position = getPositionForView(host); 2420 final ListAdapter adapter = getAdapter(); 2421 2422 if ((position == INVALID_POSITION) || (adapter == null)) { 2423 // Cannot perform actions on invalid items. 2424 return false; 2425 } 2426 2427 if (!isEnabled() || !adapter.isEnabled(position)) { 2428 // Cannot perform actions on disabled items. 2429 return false; 2430 } 2431 2432 final long id = getItemIdAtPosition(position); 2433 2434 switch (action) { 2435 case AccessibilityNodeInfo.ACTION_CLEAR_SELECTION: { 2436 if (getSelectedItemPosition() == position) { 2437 setSelection(INVALID_POSITION); 2438 return true; 2439 } 2440 } return false; 2441 case AccessibilityNodeInfo.ACTION_SELECT: { 2442 if (getSelectedItemPosition() != position) { 2443 setSelection(position); 2444 return true; 2445 } 2446 } return false; 2447 case AccessibilityNodeInfo.ACTION_CLICK: { 2448 if (isClickable()) { 2449 return performItemClick(host, position, id); 2450 } 2451 } return false; 2452 case AccessibilityNodeInfo.ACTION_LONG_CLICK: { 2453 if (isLongClickable()) { 2454 return performLongPress(host, position, id); 2455 } 2456 } return false; 2457 } 2458 2459 return false; 2460 } 2461 } 2462 2463 /** 2464 * Initializes an {@link AccessibilityNodeInfo} with information about a 2465 * particular item in the list. 2466 * 2467 * @param view View representing the list item. 2468 * @param position Position of the list item within the adapter. 2469 * @param info Node info to populate. 2470 */ 2471 public void onInitializeAccessibilityNodeInfoForItem( 2472 View view, int position, AccessibilityNodeInfo info) { 2473 final ListAdapter adapter = getAdapter(); 2474 if (position == INVALID_POSITION || adapter == null) { 2475 // The item doesn't exist, so there's not much we can do here. 2476 return; 2477 } 2478 2479 if (!isEnabled() || !adapter.isEnabled(position)) { 2480 info.setEnabled(false); 2481 return; 2482 } 2483 2484 if (position == getSelectedItemPosition()) { 2485 info.setSelected(true); 2486 info.addAction(AccessibilityNodeInfo.ACTION_CLEAR_SELECTION); 2487 } else { 2488 info.addAction(AccessibilityNodeInfo.ACTION_SELECT); 2489 } 2490 2491 if (isClickable()) { 2492 info.addAction(AccessibilityNodeInfo.ACTION_CLICK); 2493 info.setClickable(true); 2494 } 2495 2496 if (isLongClickable()) { 2497 info.addAction(AccessibilityNodeInfo.ACTION_LONG_CLICK); 2498 info.setLongClickable(true); 2499 } 2500 } 2501 2502 /** 2503 * Positions the selector in a way that mimics touch. 2504 */ 2505 void positionSelectorLikeTouch(int position, View sel, float x, float y) { 2506 positionSelectorLikeFocus(position, sel); 2507 2508 if (mSelector != null && position != INVALID_POSITION) { 2509 mSelector.setHotspot(x, y); 2510 } 2511 } 2512 2513 /** 2514 * Positions the selector in a way that mimics keyboard focus. 2515 */ 2516 void positionSelectorLikeFocus(int position, View sel) { 2517 // If we're changing position, update the visibility since the selector 2518 // is technically being detached from the previous selection. 2519 final Drawable selector = mSelector; 2520 final boolean manageState = selector != null && mSelectorPosition != position 2521 && position != INVALID_POSITION; 2522 if (manageState) { 2523 selector.setVisible(false, false); 2524 } 2525 2526 positionSelector(position, sel); 2527 2528 if (manageState) { 2529 final Rect bounds = mSelectorRect; 2530 final float x = bounds.exactCenterX(); 2531 final float y = bounds.exactCenterY(); 2532 selector.setVisible(getVisibility() == VISIBLE, false); 2533 selector.setHotspot(x, y); 2534 } 2535 } 2536 2537 void positionSelector(int position, View sel) { 2538 if (position != INVALID_POSITION) { 2539 mSelectorPosition = position; 2540 } 2541 2542 final Rect selectorRect = mSelectorRect; 2543 selectorRect.set(sel.getLeft(), sel.getTop(), sel.getRight(), sel.getBottom()); 2544 if (sel instanceof SelectionBoundsAdjuster) { 2545 ((SelectionBoundsAdjuster)sel).adjustListItemSelectionBounds(selectorRect); 2546 } 2547 2548 // Adjust for selection padding. 2549 selectorRect.left -= mSelectionLeftPadding; 2550 selectorRect.top -= mSelectionTopPadding; 2551 selectorRect.right += mSelectionRightPadding; 2552 selectorRect.bottom += mSelectionBottomPadding; 2553 2554 // Update the selector drawable. 2555 final Drawable selector = mSelector; 2556 if (selector != null) { 2557 selector.setBounds(selectorRect); 2558 } 2559 2560 final boolean isChildViewEnabled = mIsChildViewEnabled; 2561 if (sel.isEnabled() != isChildViewEnabled) { 2562 mIsChildViewEnabled = !isChildViewEnabled; 2563 if (getSelectedItemPosition() != INVALID_POSITION) { 2564 refreshDrawableState(); 2565 } 2566 } 2567 } 2568 2569 @Override 2570 protected void dispatchDraw(Canvas canvas) { 2571 int saveCount = 0; 2572 final boolean clipToPadding = (mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK; 2573 if (clipToPadding) { 2574 saveCount = canvas.save(); 2575 final int scrollX = mScrollX; 2576 final int scrollY = mScrollY; 2577 canvas.clipRect(scrollX + mPaddingLeft, scrollY + mPaddingTop, 2578 scrollX + mRight - mLeft - mPaddingRight, 2579 scrollY + mBottom - mTop - mPaddingBottom); 2580 mGroupFlags &= ~CLIP_TO_PADDING_MASK; 2581 } 2582 2583 final boolean drawSelectorOnTop = mDrawSelectorOnTop; 2584 if (!drawSelectorOnTop) { 2585 drawSelector(canvas); 2586 } 2587 2588 super.dispatchDraw(canvas); 2589 2590 if (drawSelectorOnTop) { 2591 drawSelector(canvas); 2592 } 2593 2594 if (clipToPadding) { 2595 canvas.restoreToCount(saveCount); 2596 mGroupFlags |= CLIP_TO_PADDING_MASK; 2597 } 2598 } 2599 2600 @Override 2601 protected boolean isPaddingOffsetRequired() { 2602 return (mGroupFlags & CLIP_TO_PADDING_MASK) != CLIP_TO_PADDING_MASK; 2603 } 2604 2605 @Override 2606 protected int getLeftPaddingOffset() { 2607 return (mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK ? 0 : -mPaddingLeft; 2608 } 2609 2610 @Override 2611 protected int getTopPaddingOffset() { 2612 return (mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK ? 0 : -mPaddingTop; 2613 } 2614 2615 @Override 2616 protected int getRightPaddingOffset() { 2617 return (mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK ? 0 : mPaddingRight; 2618 } 2619 2620 @Override 2621 protected int getBottomPaddingOffset() { 2622 return (mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK ? 0 : mPaddingBottom; 2623 } 2624 2625 @Override 2626 protected void onSizeChanged(int w, int h, int oldw, int oldh) { 2627 if (getChildCount() > 0) { 2628 mDataChanged = true; 2629 rememberSyncState(); 2630 } 2631 2632 if (mFastScroll != null) { 2633 mFastScroll.onSizeChanged(w, h, oldw, oldh); 2634 } 2635 } 2636 2637 /** 2638 * @return True if the current touch mode requires that we draw the selector in the pressed 2639 * state. 2640 */ 2641 boolean touchModeDrawsInPressedState() { 2642 // FIXME use isPressed for this 2643 switch (mTouchMode) { 2644 case TOUCH_MODE_TAP: 2645 case TOUCH_MODE_DONE_WAITING: 2646 return true; 2647 default: 2648 return false; 2649 } 2650 } 2651 2652 /** 2653 * Indicates whether this view is in a state where the selector should be drawn. This will 2654 * happen if we have focus but are not in touch mode, or we are in the middle of displaying 2655 * the pressed state for an item. 2656 * 2657 * @return True if the selector should be shown 2658 */ 2659 boolean shouldShowSelector() { 2660 return (!isInTouchMode()) || (touchModeDrawsInPressedState() && isPressed()); 2661 } 2662 2663 private void drawSelector(Canvas canvas) { 2664 if (!mSelectorRect.isEmpty()) { 2665 final Drawable selector = mSelector; 2666 selector.setBounds(mSelectorRect); 2667 selector.draw(canvas); 2668 } 2669 } 2670 2671 /** 2672 * Controls whether the selection highlight drawable should be drawn on top of the item or 2673 * behind it. 2674 * 2675 * @param onTop If true, the selector will be drawn on the item it is highlighting. The default 2676 * is false. 2677 * 2678 * @attr ref android.R.styleable#AbsListView_drawSelectorOnTop 2679 */ 2680 public void setDrawSelectorOnTop(boolean onTop) { 2681 mDrawSelectorOnTop = onTop; 2682 } 2683 2684 /** 2685 * Set a Drawable that should be used to highlight the currently selected item. 2686 * 2687 * @param resID A Drawable resource to use as the selection highlight. 2688 * 2689 * @attr ref android.R.styleable#AbsListView_listSelector 2690 */ 2691 public void setSelector(int resID) { 2692 setSelector(getContext().getDrawable(resID)); 2693 } 2694 2695 public void setSelector(Drawable sel) { 2696 if (mSelector != null) { 2697 mSelector.setCallback(null); 2698 unscheduleDrawable(mSelector); 2699 } 2700 mSelector = sel; 2701 Rect padding = new Rect(); 2702 sel.getPadding(padding); 2703 mSelectionLeftPadding = padding.left; 2704 mSelectionTopPadding = padding.top; 2705 mSelectionRightPadding = padding.right; 2706 mSelectionBottomPadding = padding.bottom; 2707 sel.setCallback(this); 2708 updateSelectorState(); 2709 } 2710 2711 /** 2712 * Returns the selector {@link android.graphics.drawable.Drawable} that is used to draw the 2713 * selection in the list. 2714 * 2715 * @return the drawable used to display the selector 2716 */ 2717 public Drawable getSelector() { 2718 return mSelector; 2719 } 2720 2721 /** 2722 * Sets the selector state to "pressed" and posts a CheckForKeyLongPress to see if 2723 * this is a long press. 2724 */ 2725 void keyPressed() { 2726 if (!isEnabled() || !isClickable()) { 2727 return; 2728 } 2729 2730 Drawable selector = mSelector; 2731 Rect selectorRect = mSelectorRect; 2732 if (selector != null && (isFocused() || touchModeDrawsInPressedState()) 2733 && !selectorRect.isEmpty()) { 2734 2735 final View v = getChildAt(mSelectedPosition - mFirstPosition); 2736 2737 if (v != null) { 2738 if (v.hasFocusable()) return; 2739 v.setPressed(true); 2740 } 2741 setPressed(true); 2742 2743 final boolean longClickable = isLongClickable(); 2744 Drawable d = selector.getCurrent(); 2745 if (d != null && d instanceof TransitionDrawable) { 2746 if (longClickable) { 2747 ((TransitionDrawable) d).startTransition( 2748 ViewConfiguration.getLongPressTimeout()); 2749 } else { 2750 ((TransitionDrawable) d).resetTransition(); 2751 } 2752 } 2753 if (longClickable && !mDataChanged) { 2754 if (mPendingCheckForKeyLongPress == null) { 2755 mPendingCheckForKeyLongPress = new CheckForKeyLongPress(); 2756 } 2757 mPendingCheckForKeyLongPress.rememberWindowAttachCount(); 2758 postDelayed(mPendingCheckForKeyLongPress, ViewConfiguration.getLongPressTimeout()); 2759 } 2760 } 2761 } 2762 2763 public void setScrollIndicators(View up, View down) { 2764 mScrollUp = up; 2765 mScrollDown = down; 2766 } 2767 2768 void updateSelectorState() { 2769 if (mSelector != null) { 2770 if (shouldShowSelector()) { 2771 mSelector.setState(getDrawableState()); 2772 } else { 2773 mSelector.setState(StateSet.NOTHING); 2774 } 2775 } 2776 } 2777 2778 @Override 2779 protected void drawableStateChanged() { 2780 super.drawableStateChanged(); 2781 updateSelectorState(); 2782 } 2783 2784 @Override 2785 protected int[] onCreateDrawableState(int extraSpace) { 2786 // If the child view is enabled then do the default behavior. 2787 if (mIsChildViewEnabled) { 2788 // Common case 2789 return super.onCreateDrawableState(extraSpace); 2790 } 2791 2792 // The selector uses this View's drawable state. The selected child view 2793 // is disabled, so we need to remove the enabled state from the drawable 2794 // states. 2795 final int enabledState = ENABLED_STATE_SET[0]; 2796 2797 // If we don't have any extra space, it will return one of the static state arrays, 2798 // and clearing the enabled state on those arrays is a bad thing! If we specify 2799 // we need extra space, it will create+copy into a new array that safely mutable. 2800 int[] state = super.onCreateDrawableState(extraSpace + 1); 2801 int enabledPos = -1; 2802 for (int i = state.length - 1; i >= 0; i--) { 2803 if (state[i] == enabledState) { 2804 enabledPos = i; 2805 break; 2806 } 2807 } 2808 2809 // Remove the enabled state 2810 if (enabledPos >= 0) { 2811 System.arraycopy(state, enabledPos + 1, state, enabledPos, 2812 state.length - enabledPos - 1); 2813 } 2814 2815 return state; 2816 } 2817 2818 @Override 2819 public boolean verifyDrawable(Drawable dr) { 2820 return mSelector == dr || super.verifyDrawable(dr); 2821 } 2822 2823 @Override 2824 public void jumpDrawablesToCurrentState() { 2825 super.jumpDrawablesToCurrentState(); 2826 if (mSelector != null) mSelector.jumpToCurrentState(); 2827 } 2828 2829 @Override 2830 protected void onAttachedToWindow() { 2831 super.onAttachedToWindow(); 2832 2833 final ViewTreeObserver treeObserver = getViewTreeObserver(); 2834 treeObserver.addOnTouchModeChangeListener(this); 2835 if (mTextFilterEnabled && mPopup != null && !mGlobalLayoutListenerAddedFilter) { 2836 treeObserver.addOnGlobalLayoutListener(this); 2837 } 2838 2839 if (mAdapter != null && mDataSetObserver == null) { 2840 mDataSetObserver = new AdapterDataSetObserver(); 2841 mAdapter.registerDataSetObserver(mDataSetObserver); 2842 2843 // Data may have changed while we were detached. Refresh. 2844 mDataChanged = true; 2845 mOldItemCount = mItemCount; 2846 mItemCount = mAdapter.getCount(); 2847 } 2848 } 2849 2850 @Override 2851 protected void onDetachedFromWindow() { 2852 super.onDetachedFromWindow(); 2853 2854 mIsDetaching = true; 2855 2856 // Dismiss the popup in case onSaveInstanceState() was not invoked 2857 dismissPopup(); 2858 2859 // Detach any view left in the scrap heap 2860 mRecycler.clear(); 2861 2862 final ViewTreeObserver treeObserver = getViewTreeObserver(); 2863 treeObserver.removeOnTouchModeChangeListener(this); 2864 if (mTextFilterEnabled && mPopup != null) { 2865 treeObserver.removeOnGlobalLayoutListener(this); 2866 mGlobalLayoutListenerAddedFilter = false; 2867 } 2868 2869 if (mAdapter != null && mDataSetObserver != null) { 2870 mAdapter.unregisterDataSetObserver(mDataSetObserver); 2871 mDataSetObserver = null; 2872 } 2873 2874 if (mScrollStrictSpan != null) { 2875 mScrollStrictSpan.finish(); 2876 mScrollStrictSpan = null; 2877 } 2878 2879 if (mFlingStrictSpan != null) { 2880 mFlingStrictSpan.finish(); 2881 mFlingStrictSpan = null; 2882 } 2883 2884 if (mFlingRunnable != null) { 2885 removeCallbacks(mFlingRunnable); 2886 } 2887 2888 if (mPositionScroller != null) { 2889 mPositionScroller.stop(); 2890 } 2891 2892 if (mClearScrollingCache != null) { 2893 removeCallbacks(mClearScrollingCache); 2894 } 2895 2896 if (mPerformClick != null) { 2897 removeCallbacks(mPerformClick); 2898 } 2899 2900 if (mTouchModeReset != null) { 2901 removeCallbacks(mTouchModeReset); 2902 mTouchModeReset.run(); 2903 } 2904 2905 mIsDetaching = false; 2906 } 2907 2908 @Override 2909 public void onWindowFocusChanged(boolean hasWindowFocus) { 2910 super.onWindowFocusChanged(hasWindowFocus); 2911 2912 final int touchMode = isInTouchMode() ? TOUCH_MODE_ON : TOUCH_MODE_OFF; 2913 2914 if (!hasWindowFocus) { 2915 setChildrenDrawingCacheEnabled(false); 2916 if (mFlingRunnable != null) { 2917 removeCallbacks(mFlingRunnable); 2918 // let the fling runnable report it's new state which 2919 // should be idle 2920 mFlingRunnable.endFling(); 2921 if (mPositionScroller != null) { 2922 mPositionScroller.stop(); 2923 } 2924 if (mScrollY != 0) { 2925 mScrollY = 0; 2926 invalidateParentCaches(); 2927 finishGlows(); 2928 invalidate(); 2929 } 2930 } 2931 // Always hide the type filter 2932 dismissPopup(); 2933 2934 if (touchMode == TOUCH_MODE_OFF) { 2935 // Remember the last selected element 2936 mResurrectToPosition = mSelectedPosition; 2937 } 2938 } else { 2939 if (mFiltered && !mPopupHidden) { 2940 // Show the type filter only if a filter is in effect 2941 showPopup(); 2942 } 2943 2944 // If we changed touch mode since the last time we had focus 2945 if (touchMode != mLastTouchMode && mLastTouchMode != TOUCH_MODE_UNKNOWN) { 2946 // If we come back in trackball mode, we bring the selection back 2947 if (touchMode == TOUCH_MODE_OFF) { 2948 // This will trigger a layout 2949 resurrectSelection(); 2950 2951 // If we come back in touch mode, then we want to hide the selector 2952 } else { 2953 hideSelector(); 2954 mLayoutMode = LAYOUT_NORMAL; 2955 layoutChildren(); 2956 } 2957 } 2958 } 2959 2960 mLastTouchMode = touchMode; 2961 } 2962 2963 @Override 2964 public void onRtlPropertiesChanged(int layoutDirection) { 2965 super.onRtlPropertiesChanged(layoutDirection); 2966 if (mFastScroll != null) { 2967 mFastScroll.setScrollbarPosition(getVerticalScrollbarPosition()); 2968 } 2969 } 2970 2971 /** 2972 * Creates the ContextMenuInfo returned from {@link #getContextMenuInfo()}. This 2973 * methods knows the view, position and ID of the item that received the 2974 * long press. 2975 * 2976 * @param view The view that received the long press. 2977 * @param position The position of the item that received the long press. 2978 * @param id The ID of the item that received the long press. 2979 * @return The extra information that should be returned by 2980 * {@link #getContextMenuInfo()}. 2981 */ 2982 ContextMenuInfo createContextMenuInfo(View view, int position, long id) { 2983 return new AdapterContextMenuInfo(view, position, id); 2984 } 2985 2986 @Override 2987 public void onCancelPendingInputEvents() { 2988 super.onCancelPendingInputEvents(); 2989 if (mPerformClick != null) { 2990 removeCallbacks(mPerformClick); 2991 } 2992 if (mPendingCheckForTap != null) { 2993 removeCallbacks(mPendingCheckForTap); 2994 } 2995 if (mPendingCheckForLongPress != null) { 2996 removeCallbacks(mPendingCheckForLongPress); 2997 } 2998 if (mPendingCheckForKeyLongPress != null) { 2999 removeCallbacks(mPendingCheckForKeyLongPress); 3000 } 3001 } 3002 3003 /** 3004 * A base class for Runnables that will check that their view is still attached to 3005 * the original window as when the Runnable was created. 3006 * 3007 */ 3008 private class WindowRunnnable { 3009 private int mOriginalAttachCount; 3010 3011 public void rememberWindowAttachCount() { 3012 mOriginalAttachCount = getWindowAttachCount(); 3013 } 3014 3015 public boolean sameWindow() { 3016 return getWindowAttachCount() == mOriginalAttachCount; 3017 } 3018 } 3019 3020 private class PerformClick extends WindowRunnnable implements Runnable { 3021 int mClickMotionPosition; 3022 3023 @Override 3024 public void run() { 3025 // The data has changed since we posted this action in the event queue, 3026 // bail out before bad things happen 3027 if (mDataChanged) return; 3028 3029 final ListAdapter adapter = mAdapter; 3030 final int motionPosition = mClickMotionPosition; 3031 if (adapter != null && mItemCount > 0 && 3032 motionPosition != INVALID_POSITION && 3033 motionPosition < adapter.getCount() && sameWindow()) { 3034 final View view = getChildAt(motionPosition - mFirstPosition); 3035 // If there is no view, something bad happened (the view scrolled off the 3036 // screen, etc.) and we should cancel the click 3037 if (view != null) { 3038 performItemClick(view, motionPosition, adapter.getItemId(motionPosition)); 3039 } 3040 } 3041 } 3042 } 3043 3044 private class CheckForLongPress extends WindowRunnnable implements Runnable { 3045 @Override 3046 public void run() { 3047 final int motionPosition = mMotionPosition; 3048 final View child = getChildAt(motionPosition - mFirstPosition); 3049 if (child != null) { 3050 final int longPressPosition = mMotionPosition; 3051 final long longPressId = mAdapter.getItemId(mMotionPosition); 3052 3053 boolean handled = false; 3054 if (sameWindow() && !mDataChanged) { 3055 handled = performLongPress(child, longPressPosition, longPressId); 3056 } 3057 if (handled) { 3058 mTouchMode = TOUCH_MODE_REST; 3059 setPressed(false); 3060 child.setPressed(false); 3061 } else { 3062 mTouchMode = TOUCH_MODE_DONE_WAITING; 3063 } 3064 } 3065 } 3066 } 3067 3068 private class CheckForKeyLongPress extends WindowRunnnable implements Runnable { 3069 @Override 3070 public void run() { 3071 if (isPressed() && mSelectedPosition >= 0) { 3072 int index = mSelectedPosition - mFirstPosition; 3073 View v = getChildAt(index); 3074 3075 if (!mDataChanged) { 3076 boolean handled = false; 3077 if (sameWindow()) { 3078 handled = performLongPress(v, mSelectedPosition, mSelectedRowId); 3079 } 3080 if (handled) { 3081 setPressed(false); 3082 v.setPressed(false); 3083 } 3084 } else { 3085 setPressed(false); 3086 if (v != null) v.setPressed(false); 3087 } 3088 } 3089 } 3090 } 3091 3092 boolean performLongPress(final View child, 3093 final int longPressPosition, final long longPressId) { 3094 // CHOICE_MODE_MULTIPLE_MODAL takes over long press. 3095 if (mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL) { 3096 if (mChoiceActionMode == null && 3097 (mChoiceActionMode = startActionMode(mMultiChoiceModeCallback)) != null) { 3098 setItemChecked(longPressPosition, true); 3099 performHapticFeedback(HapticFeedbackConstants.LONG_PRESS); 3100 } 3101 return true; 3102 } 3103 3104 boolean handled = false; 3105 if (mOnItemLongClickListener != null) { 3106 handled = mOnItemLongClickListener.onItemLongClick(AbsListView.this, child, 3107 longPressPosition, longPressId); 3108 } 3109 if (!handled) { 3110 mContextMenuInfo = createContextMenuInfo(child, longPressPosition, longPressId); 3111 handled = super.showContextMenuForChild(AbsListView.this); 3112 } 3113 if (handled) { 3114 performHapticFeedback(HapticFeedbackConstants.LONG_PRESS); 3115 } 3116 return handled; 3117 } 3118 3119 @Override 3120 protected ContextMenuInfo getContextMenuInfo() { 3121 return mContextMenuInfo; 3122 } 3123 3124 /** @hide */ 3125 @Override 3126 public boolean showContextMenu(float x, float y, int metaState) { 3127 final int position = pointToPosition((int)x, (int)y); 3128 if (position != INVALID_POSITION) { 3129 final long id = mAdapter.getItemId(position); 3130 View child = getChildAt(position - mFirstPosition); 3131 if (child != null) { 3132 mContextMenuInfo = createContextMenuInfo(child, position, id); 3133 return super.showContextMenuForChild(AbsListView.this); 3134 } 3135 } 3136 return super.showContextMenu(x, y, metaState); 3137 } 3138 3139 @Override 3140 public boolean showContextMenuForChild(View originalView) { 3141 final int longPressPosition = getPositionForView(originalView); 3142 if (longPressPosition >= 0) { 3143 final long longPressId = mAdapter.getItemId(longPressPosition); 3144 boolean handled = false; 3145 3146 if (mOnItemLongClickListener != null) { 3147 handled = mOnItemLongClickListener.onItemLongClick(AbsListView.this, originalView, 3148 longPressPosition, longPressId); 3149 } 3150 if (!handled) { 3151 mContextMenuInfo = createContextMenuInfo( 3152 getChildAt(longPressPosition - mFirstPosition), 3153 longPressPosition, longPressId); 3154 handled = super.showContextMenuForChild(originalView); 3155 } 3156 3157 return handled; 3158 } 3159 return false; 3160 } 3161 3162 @Override 3163 public boolean onKeyDown(int keyCode, KeyEvent event) { 3164 return false; 3165 } 3166 3167 @Override 3168 public boolean onKeyUp(int keyCode, KeyEvent event) { 3169 if (KeyEvent.isConfirmKey(keyCode)) { 3170 if (!isEnabled()) { 3171 return true; 3172 } 3173 if (isClickable() && isPressed() && 3174 mSelectedPosition >= 0 && mAdapter != null && 3175 mSelectedPosition < mAdapter.getCount()) { 3176 3177 final View view = getChildAt(mSelectedPosition - mFirstPosition); 3178 if (view != null) { 3179 performItemClick(view, mSelectedPosition, mSelectedRowId); 3180 view.setPressed(false); 3181 } 3182 setPressed(false); 3183 return true; 3184 } 3185 } 3186 return super.onKeyUp(keyCode, event); 3187 } 3188 3189 @Override 3190 protected void dispatchSetPressed(boolean pressed) { 3191 // Don't dispatch setPressed to our children. We call setPressed on ourselves to 3192 // get the selector in the right state, but we don't want to press each child. 3193 } 3194 3195 /** 3196 * Maps a point to a position in the list. 3197 * 3198 * @param x X in local coordinate 3199 * @param y Y in local coordinate 3200 * @return The position of the item which contains the specified point, or 3201 * {@link #INVALID_POSITION} if the point does not intersect an item. 3202 */ 3203 public int pointToPosition(int x, int y) { 3204 Rect frame = mTouchFrame; 3205 if (frame == null) { 3206 mTouchFrame = new Rect(); 3207 frame = mTouchFrame; 3208 } 3209 3210 final int count = getChildCount(); 3211 for (int i = count - 1; i >= 0; i--) { 3212 final View child = getChildAt(i); 3213 if (child.getVisibility() == View.VISIBLE) { 3214 child.getHitRect(frame); 3215 if (frame.contains(x, y)) { 3216 return mFirstPosition + i; 3217 } 3218 } 3219 } 3220 return INVALID_POSITION; 3221 } 3222 3223 3224 /** 3225 * Maps a point to a the rowId of the item which intersects that point. 3226 * 3227 * @param x X in local coordinate 3228 * @param y Y in local coordinate 3229 * @return The rowId of the item which contains the specified point, or {@link #INVALID_ROW_ID} 3230 * if the point does not intersect an item. 3231 */ 3232 public long pointToRowId(int x, int y) { 3233 int position = pointToPosition(x, y); 3234 if (position >= 0) { 3235 return mAdapter.getItemId(position); 3236 } 3237 return INVALID_ROW_ID; 3238 } 3239 3240 private final class CheckForTap implements Runnable { 3241 float x; 3242 float y; 3243 3244 @Override 3245 public void run() { 3246 if (mTouchMode == TOUCH_MODE_DOWN) { 3247 mTouchMode = TOUCH_MODE_TAP; 3248 final View child = getChildAt(mMotionPosition - mFirstPosition); 3249 if (child != null && !child.hasFocusable()) { 3250 mLayoutMode = LAYOUT_NORMAL; 3251 3252 if (!mDataChanged) { 3253 child.setPressed(true); 3254 setPressed(true); 3255 layoutChildren(); 3256 positionSelector(mMotionPosition, child); 3257 refreshDrawableState(); 3258 3259 final int longPressTimeout = ViewConfiguration.getLongPressTimeout(); 3260 final boolean longClickable = isLongClickable(); 3261 3262 if (mSelector != null) { 3263 final Drawable d = mSelector.getCurrent(); 3264 if (d != null && d instanceof TransitionDrawable) { 3265 if (longClickable) { 3266 ((TransitionDrawable) d).startTransition(longPressTimeout); 3267 } else { 3268 ((TransitionDrawable) d).resetTransition(); 3269 } 3270 } 3271 mSelector.setHotspot(x, y); 3272 } 3273 3274 if (longClickable) { 3275 if (mPendingCheckForLongPress == null) { 3276 mPendingCheckForLongPress = new CheckForLongPress(); 3277 } 3278 mPendingCheckForLongPress.rememberWindowAttachCount(); 3279 postDelayed(mPendingCheckForLongPress, longPressTimeout); 3280 } else { 3281 mTouchMode = TOUCH_MODE_DONE_WAITING; 3282 } 3283 } else { 3284 mTouchMode = TOUCH_MODE_DONE_WAITING; 3285 } 3286 } 3287 } 3288 } 3289 } 3290 3291 private boolean startScrollIfNeeded(int x, int y, MotionEvent vtev) { 3292 // Check if we have moved far enough that it looks more like a 3293 // scroll than a tap 3294 final int deltaY = y - mMotionY; 3295 final int distance = Math.abs(deltaY); 3296 final boolean overscroll = mScrollY != 0; 3297 if ((overscroll || distance > mTouchSlop) && 3298 (getNestedScrollAxes() & SCROLL_AXIS_VERTICAL) == 0) { 3299 createScrollingCache(); 3300 if (overscroll) { 3301 mTouchMode = TOUCH_MODE_OVERSCROLL; 3302 mMotionCorrection = 0; 3303 } else { 3304 mTouchMode = TOUCH_MODE_SCROLL; 3305 mMotionCorrection = deltaY > 0 ? mTouchSlop : -mTouchSlop; 3306 } 3307 removeCallbacks(mPendingCheckForLongPress); 3308 setPressed(false); 3309 final View motionView = getChildAt(mMotionPosition - mFirstPosition); 3310 if (motionView != null) { 3311 motionView.setPressed(false); 3312 } 3313 reportScrollStateChange(OnScrollListener.SCROLL_STATE_TOUCH_SCROLL); 3314 // Time to start stealing events! Once we've stolen them, don't let anyone 3315 // steal from us 3316 final ViewParent parent = getParent(); 3317 if (parent != null) { 3318 parent.requestDisallowInterceptTouchEvent(true); 3319 } 3320 scrollIfNeeded(x, y, vtev); 3321 return true; 3322 } 3323 3324 return false; 3325 } 3326 3327 private void scrollIfNeeded(int x, int y, MotionEvent vtev) { 3328 int rawDeltaY = y - mMotionY; 3329 int scrollOffsetCorrection = 0; 3330 int scrollConsumedCorrection = 0; 3331 if (mLastY == Integer.MIN_VALUE) { 3332 rawDeltaY -= mMotionCorrection; 3333 } 3334 if (dispatchNestedPreScroll(0, mLastY != Integer.MIN_VALUE ? mLastY - y : -rawDeltaY, 3335 mScrollConsumed, mScrollOffset)) { 3336 rawDeltaY += mScrollConsumed[1]; 3337 scrollOffsetCorrection = -mScrollOffset[1]; 3338 scrollConsumedCorrection = mScrollConsumed[1]; 3339 if (vtev != null) { 3340 vtev.offsetLocation(0, mScrollOffset[1]); 3341 } 3342 } 3343 final int deltaY = rawDeltaY; 3344 int incrementalDeltaY = 3345 mLastY != Integer.MIN_VALUE ? y - mLastY + scrollConsumedCorrection : deltaY; 3346 int lastYCorrection = 0; 3347 3348 if (mTouchMode == TOUCH_MODE_SCROLL) { 3349 if (PROFILE_SCROLLING) { 3350 if (!mScrollProfilingStarted) { 3351 Debug.startMethodTracing("AbsListViewScroll"); 3352 mScrollProfilingStarted = true; 3353 } 3354 } 3355 3356 if (mScrollStrictSpan == null) { 3357 // If it's non-null, we're already in a scroll. 3358 mScrollStrictSpan = StrictMode.enterCriticalSpan("AbsListView-scroll"); 3359 } 3360 3361 if (y != mLastY) { 3362 // We may be here after stopping a fling and continuing to scroll. 3363 // If so, we haven't disallowed intercepting touch events yet. 3364 // Make sure that we do so in case we're in a parent that can intercept. 3365 if ((mGroupFlags & FLAG_DISALLOW_INTERCEPT) == 0 && 3366 Math.abs(rawDeltaY) > mTouchSlop) { 3367 final ViewParent parent = getParent(); 3368 if (parent != null) { 3369 parent.requestDisallowInterceptTouchEvent(true); 3370 } 3371 } 3372 3373 final int motionIndex; 3374 if (mMotionPosition >= 0) { 3375 motionIndex = mMotionPosition - mFirstPosition; 3376 } else { 3377 // If we don't have a motion position that we can reliably track, 3378 // pick something in the middle to make a best guess at things below. 3379 motionIndex = getChildCount() / 2; 3380 } 3381 3382 int motionViewPrevTop = 0; 3383 View motionView = this.getChildAt(motionIndex); 3384 if (motionView != null) { 3385 motionViewPrevTop = motionView.getTop(); 3386 } 3387 3388 // No need to do all this work if we're not going to move anyway 3389 boolean atEdge = false; 3390 if (incrementalDeltaY != 0) { 3391 atEdge = trackMotionScroll(deltaY, incrementalDeltaY); 3392 } 3393 3394 // Check to see if we have bumped into the scroll limit 3395 motionView = this.getChildAt(motionIndex); 3396 if (motionView != null) { 3397 // Check if the top of the motion view is where it is 3398 // supposed to be 3399 final int motionViewRealTop = motionView.getTop(); 3400 if (atEdge) { 3401 // Apply overscroll 3402 3403 int overscroll = -incrementalDeltaY - 3404 (motionViewRealTop - motionViewPrevTop); 3405 if (dispatchNestedScroll(0, overscroll - incrementalDeltaY, 0, overscroll, 3406 mScrollOffset)) { 3407 lastYCorrection -= mScrollOffset[1]; 3408 if (vtev != null) { 3409 vtev.offsetLocation(0, mScrollOffset[1]); 3410 } 3411 } else { 3412 final boolean atOverscrollEdge = overScrollBy(0, overscroll, 3413 0, mScrollY, 0, 0, 0, mOverscrollDistance, true); 3414 3415 if (atOverscrollEdge && mVelocityTracker != null) { 3416 // Don't allow overfling if we're at the edge 3417 mVelocityTracker.clear(); 3418 } 3419 3420 final int overscrollMode = getOverScrollMode(); 3421 if (overscrollMode == OVER_SCROLL_ALWAYS || 3422 (overscrollMode == OVER_SCROLL_IF_CONTENT_SCROLLS && 3423 !contentFits())) { 3424 if (!atOverscrollEdge) { 3425 mDirection = 0; // Reset when entering overscroll. 3426 mTouchMode = TOUCH_MODE_OVERSCROLL; 3427 } 3428 if (incrementalDeltaY > 0) { 3429 mEdgeGlowTop.onPull((float) -overscroll / getHeight(), 3430 (float) x / getWidth()); 3431 if (!mEdgeGlowBottom.isFinished()) { 3432 mEdgeGlowBottom.onRelease(); 3433 } 3434 invalidate(0, 0, getWidth(), 3435 mEdgeGlowTop.getMaxHeight() + getPaddingTop()); 3436 } else if (incrementalDeltaY < 0) { 3437 mEdgeGlowBottom.onPull((float) overscroll / getHeight(), 3438 1.f - (float) x / getWidth()); 3439 if (!mEdgeGlowTop.isFinished()) { 3440 mEdgeGlowTop.onRelease(); 3441 } 3442 invalidate(0, getHeight() - getPaddingBottom() - 3443 mEdgeGlowBottom.getMaxHeight(), getWidth(), 3444 getHeight()); 3445 } 3446 } 3447 } 3448 } 3449 mMotionY = y + lastYCorrection + scrollOffsetCorrection; 3450 } 3451 mLastY = y + lastYCorrection + scrollOffsetCorrection; 3452 } 3453 } else if (mTouchMode == TOUCH_MODE_OVERSCROLL) { 3454 if (y != mLastY) { 3455 final int oldScroll = mScrollY; 3456 final int newScroll = oldScroll - incrementalDeltaY; 3457 int newDirection = y > mLastY ? 1 : -1; 3458 3459 if (mDirection == 0) { 3460 mDirection = newDirection; 3461 } 3462 3463 int overScrollDistance = -incrementalDeltaY; 3464 if ((newScroll < 0 && oldScroll >= 0) || (newScroll > 0 && oldScroll <= 0)) { 3465 overScrollDistance = -oldScroll; 3466 incrementalDeltaY += overScrollDistance; 3467 } else { 3468 incrementalDeltaY = 0; 3469 } 3470 3471 if (overScrollDistance != 0) { 3472 overScrollBy(0, overScrollDistance, 0, mScrollY, 0, 0, 3473 0, mOverscrollDistance, true); 3474 final int overscrollMode = getOverScrollMode(); 3475 if (overscrollMode == OVER_SCROLL_ALWAYS || 3476 (overscrollMode == OVER_SCROLL_IF_CONTENT_SCROLLS && 3477 !contentFits())) { 3478 if (rawDeltaY > 0) { 3479 mEdgeGlowTop.onPull((float) overScrollDistance / getHeight(), 3480 (float) x / getWidth()); 3481 if (!mEdgeGlowBottom.isFinished()) { 3482 mEdgeGlowBottom.onRelease(); 3483 } 3484 invalidate(0, 0, getWidth(), 3485 mEdgeGlowTop.getMaxHeight() + getPaddingTop()); 3486 } else if (rawDeltaY < 0) { 3487 mEdgeGlowBottom.onPull((float) overScrollDistance / getHeight(), 3488 1.f - (float) x / getWidth()); 3489 if (!mEdgeGlowTop.isFinished()) { 3490 mEdgeGlowTop.onRelease(); 3491 } 3492 invalidate(0, getHeight() - getPaddingBottom() - 3493 mEdgeGlowBottom.getMaxHeight(), getWidth(), 3494 getHeight()); 3495 } 3496 } 3497 } 3498 3499 if (incrementalDeltaY != 0) { 3500 // Coming back to 'real' list scrolling 3501 if (mScrollY != 0) { 3502 mScrollY = 0; 3503 invalidateParentIfNeeded(); 3504 } 3505 3506 trackMotionScroll(incrementalDeltaY, incrementalDeltaY); 3507 3508 mTouchMode = TOUCH_MODE_SCROLL; 3509 3510 // We did not scroll the full amount. Treat this essentially like the 3511 // start of a new touch scroll 3512 final int motionPosition = findClosestMotionRow(y); 3513 3514 mMotionCorrection = 0; 3515 View motionView = getChildAt(motionPosition - mFirstPosition); 3516 mMotionViewOriginalTop = motionView != null ? motionView.getTop() : 0; 3517 mMotionY = y + scrollOffsetCorrection; 3518 mMotionPosition = motionPosition; 3519 } 3520 mLastY = y + lastYCorrection + scrollOffsetCorrection; 3521 mDirection = newDirection; 3522 } 3523 } 3524 } 3525 3526 @Override 3527 public void onTouchModeChanged(boolean isInTouchMode) { 3528 if (isInTouchMode) { 3529 // Get rid of the selection when we enter touch mode 3530 hideSelector(); 3531 // Layout, but only if we already have done so previously. 3532 // (Otherwise may clobber a LAYOUT_SYNC layout that was requested to restore 3533 // state.) 3534 if (getHeight() > 0 && getChildCount() > 0) { 3535 // We do not lose focus initiating a touch (since AbsListView is focusable in 3536 // touch mode). Force an initial layout to get rid of the selection. 3537 layoutChildren(); 3538 } 3539 updateSelectorState(); 3540 } else { 3541 int touchMode = mTouchMode; 3542 if (touchMode == TOUCH_MODE_OVERSCROLL || touchMode == TOUCH_MODE_OVERFLING) { 3543 if (mFlingRunnable != null) { 3544 mFlingRunnable.endFling(); 3545 } 3546 if (mPositionScroller != null) { 3547 mPositionScroller.stop(); 3548 } 3549 3550 if (mScrollY != 0) { 3551 mScrollY = 0; 3552 invalidateParentCaches(); 3553 finishGlows(); 3554 invalidate(); 3555 } 3556 } 3557 } 3558 } 3559 3560 @Override 3561 public boolean onTouchEvent(MotionEvent ev) { 3562 if (!isEnabled()) { 3563 // A disabled view that is clickable still consumes the touch 3564 // events, it just doesn't respond to them. 3565 return isClickable() || isLongClickable(); 3566 } 3567 3568 if (mPositionScroller != null) { 3569 mPositionScroller.stop(); 3570 } 3571 3572 if (mIsDetaching || !isAttachedToWindow()) { 3573 // Something isn't right. 3574 // Since we rely on being attached to get data set change notifications, 3575 // don't risk doing anything where we might try to resync and find things 3576 // in a bogus state. 3577 return false; 3578 } 3579 3580 startNestedScroll(SCROLL_AXIS_VERTICAL); 3581 3582 if (mFastScroll != null) { 3583 boolean intercepted = mFastScroll.onTouchEvent(ev); 3584 if (intercepted) { 3585 return true; 3586 } 3587 } 3588 3589 initVelocityTrackerIfNotExists(); 3590 final MotionEvent vtev = MotionEvent.obtain(ev); 3591 3592 final int actionMasked = ev.getActionMasked(); 3593 switch (actionMasked) { 3594 case MotionEvent.ACTION_DOWN: { 3595 onTouchDown(ev); 3596 break; 3597 } 3598 3599 case MotionEvent.ACTION_MOVE: { 3600 onTouchMove(ev, vtev); 3601 break; 3602 } 3603 3604 case MotionEvent.ACTION_UP: { 3605 onTouchUp(ev); 3606 break; 3607 } 3608 3609 case MotionEvent.ACTION_CANCEL: { 3610 onTouchCancel(); 3611 break; 3612 } 3613 3614 case MotionEvent.ACTION_POINTER_UP: { 3615 onSecondaryPointerUp(ev); 3616 final int x = mMotionX; 3617 final int y = mMotionY; 3618 final int motionPosition = pointToPosition(x, y); 3619 if (motionPosition >= 0) { 3620 // Remember where the motion event started 3621 final View child = getChildAt(motionPosition - mFirstPosition); 3622 mMotionViewOriginalTop = child.getTop(); 3623 mMotionPosition = motionPosition; 3624 } 3625 mLastY = y; 3626 break; 3627 } 3628 3629 case MotionEvent.ACTION_POINTER_DOWN: { 3630 // New pointers take over dragging duties 3631 final int index = ev.getActionIndex(); 3632 final int id = ev.getPointerId(index); 3633 final int x = (int) ev.getX(index); 3634 final int y = (int) ev.getY(index); 3635 mMotionCorrection = 0; 3636 mActivePointerId = id; 3637 mMotionX = x; 3638 mMotionY = y; 3639 final int motionPosition = pointToPosition(x, y); 3640 if (motionPosition >= 0) { 3641 // Remember where the motion event started 3642 final View child = getChildAt(motionPosition - mFirstPosition); 3643 mMotionViewOriginalTop = child.getTop(); 3644 mMotionPosition = motionPosition; 3645 } 3646 mLastY = y; 3647 break; 3648 } 3649 } 3650 3651 if (mVelocityTracker != null) { 3652 mVelocityTracker.addMovement(vtev); 3653 } 3654 vtev.recycle(); 3655 return true; 3656 } 3657 3658 private void onTouchDown(MotionEvent ev) { 3659 mActivePointerId = ev.getPointerId(0); 3660 3661 if (mTouchMode == TOUCH_MODE_OVERFLING) { 3662 // Stopped the fling. It is a scroll. 3663 mFlingRunnable.endFling(); 3664 if (mPositionScroller != null) { 3665 mPositionScroller.stop(); 3666 } 3667 mTouchMode = TOUCH_MODE_OVERSCROLL; 3668 mMotionX = (int) ev.getX(); 3669 mMotionY = (int) ev.getY(); 3670 mLastY = mMotionY; 3671 mMotionCorrection = 0; 3672 mDirection = 0; 3673 } else { 3674 final int x = (int) ev.getX(); 3675 final int y = (int) ev.getY(); 3676 int motionPosition = pointToPosition(x, y); 3677 3678 if (!mDataChanged) { 3679 if (mTouchMode == TOUCH_MODE_FLING) { 3680 // Stopped a fling. It is a scroll. 3681 createScrollingCache(); 3682 mTouchMode = TOUCH_MODE_SCROLL; 3683 mMotionCorrection = 0; 3684 motionPosition = findMotionRow(y); 3685 mFlingRunnable.flywheelTouch(); 3686 } else if ((motionPosition >= 0) && getAdapter().isEnabled(motionPosition)) { 3687 // User clicked on an actual view (and was not stopping a 3688 // fling). It might be a click or a scroll. Assume it is a 3689 // click until proven otherwise. 3690 mTouchMode = TOUCH_MODE_DOWN; 3691 3692 // FIXME Debounce 3693 if (mPendingCheckForTap == null) { 3694 mPendingCheckForTap = new CheckForTap(); 3695 } 3696 3697 mPendingCheckForTap.x = ev.getX(); 3698 mPendingCheckForTap.y = ev.getY(); 3699 postDelayed(mPendingCheckForTap, ViewConfiguration.getTapTimeout()); 3700 } 3701 } 3702 3703 if (motionPosition >= 0) { 3704 // Remember where the motion event started 3705 final View v = getChildAt(motionPosition - mFirstPosition); 3706 mMotionViewOriginalTop = v.getTop(); 3707 } 3708 3709 mMotionX = x; 3710 mMotionY = y; 3711 mMotionPosition = motionPosition; 3712 mLastY = Integer.MIN_VALUE; 3713 } 3714 3715 if (mTouchMode == TOUCH_MODE_DOWN && mMotionPosition != INVALID_POSITION 3716 && performButtonActionOnTouchDown(ev)) { 3717 removeCallbacks(mPendingCheckForTap); 3718 } 3719 } 3720 3721 private void onTouchMove(MotionEvent ev, MotionEvent vtev) { 3722 int pointerIndex = ev.findPointerIndex(mActivePointerId); 3723 if (pointerIndex == -1) { 3724 pointerIndex = 0; 3725 mActivePointerId = ev.getPointerId(pointerIndex); 3726 } 3727 3728 if (mDataChanged) { 3729 // Re-sync everything if data has been changed 3730 // since the scroll operation can query the adapter. 3731 layoutChildren(); 3732 } 3733 3734 final int y = (int) ev.getY(pointerIndex); 3735 3736 switch (mTouchMode) { 3737 case TOUCH_MODE_DOWN: 3738 case TOUCH_MODE_TAP: 3739 case TOUCH_MODE_DONE_WAITING: 3740 // Check if we have moved far enough that it looks more like a 3741 // scroll than a tap. If so, we'll enter scrolling mode. 3742 if (startScrollIfNeeded((int) ev.getX(pointerIndex), y, vtev)) { 3743 break; 3744 } 3745 // Otherwise, check containment within list bounds. If we're 3746 // outside bounds, cancel any active presses. 3747 final float x = ev.getX(pointerIndex); 3748 if (!pointInView(x, y, mTouchSlop)) { 3749 setPressed(false); 3750 final View motionView = getChildAt(mMotionPosition - mFirstPosition); 3751 if (motionView != null) { 3752 motionView.setPressed(false); 3753 } 3754 removeCallbacks(mTouchMode == TOUCH_MODE_DOWN ? 3755 mPendingCheckForTap : mPendingCheckForLongPress); 3756 mTouchMode = TOUCH_MODE_DONE_WAITING; 3757 updateSelectorState(); 3758 } 3759 break; 3760 case TOUCH_MODE_SCROLL: 3761 case TOUCH_MODE_OVERSCROLL: 3762 scrollIfNeeded((int) ev.getX(pointerIndex), y, vtev); 3763 break; 3764 } 3765 } 3766 3767 private void onTouchUp(MotionEvent ev) { 3768 switch (mTouchMode) { 3769 case TOUCH_MODE_DOWN: 3770 case TOUCH_MODE_TAP: 3771 case TOUCH_MODE_DONE_WAITING: 3772 final int motionPosition = mMotionPosition; 3773 final View child = getChildAt(motionPosition - mFirstPosition); 3774 if (child != null) { 3775 if (mTouchMode != TOUCH_MODE_DOWN) { 3776 child.setPressed(false); 3777 } 3778 3779 final float x = ev.getX(); 3780 final boolean inList = x > mListPadding.left && x < getWidth() - mListPadding.right; 3781 if (inList && !child.hasFocusable()) { 3782 if (mPerformClick == null) { 3783 mPerformClick = new PerformClick(); 3784 } 3785 3786 final AbsListView.PerformClick performClick = mPerformClick; 3787 performClick.mClickMotionPosition = motionPosition; 3788 performClick.rememberWindowAttachCount(); 3789 3790 mResurrectToPosition = motionPosition; 3791 3792 if (mTouchMode == TOUCH_MODE_DOWN || mTouchMode == TOUCH_MODE_TAP) { 3793 removeCallbacks(mTouchMode == TOUCH_MODE_DOWN ? 3794 mPendingCheckForTap : mPendingCheckForLongPress); 3795 mLayoutMode = LAYOUT_NORMAL; 3796 if (!mDataChanged && mAdapter.isEnabled(motionPosition)) { 3797 mTouchMode = TOUCH_MODE_TAP; 3798 setSelectedPositionInt(mMotionPosition); 3799 layoutChildren(); 3800 child.setPressed(true); 3801 positionSelector(mMotionPosition, child); 3802 setPressed(true); 3803 if (mSelector != null) { 3804 Drawable d = mSelector.getCurrent(); 3805 if (d != null && d instanceof TransitionDrawable) { 3806 ((TransitionDrawable) d).resetTransition(); 3807 } 3808 mSelector.setHotspot(x, ev.getY()); 3809 } 3810 if (mTouchModeReset != null) { 3811 removeCallbacks(mTouchModeReset); 3812 } 3813 mTouchModeReset = new Runnable() { 3814 @Override 3815 public void run() { 3816 mTouchModeReset = null; 3817 mTouchMode = TOUCH_MODE_REST; 3818 child.setPressed(false); 3819 setPressed(false); 3820 if (!mDataChanged && !mIsDetaching && isAttachedToWindow()) { 3821 performClick.run(); 3822 } 3823 } 3824 }; 3825 postDelayed(mTouchModeReset, 3826 ViewConfiguration.getPressedStateDuration()); 3827 } else { 3828 mTouchMode = TOUCH_MODE_REST; 3829 updateSelectorState(); 3830 } 3831 return; 3832 } else if (!mDataChanged && mAdapter.isEnabled(motionPosition)) { 3833 performClick.run(); 3834 } 3835 } 3836 } 3837 mTouchMode = TOUCH_MODE_REST; 3838 updateSelectorState(); 3839 break; 3840 case TOUCH_MODE_SCROLL: 3841 final int childCount = getChildCount(); 3842 if (childCount > 0) { 3843 final int firstChildTop = getChildAt(0).getTop(); 3844 final int lastChildBottom = getChildAt(childCount - 1).getBottom(); 3845 final int contentTop = mListPadding.top; 3846 final int contentBottom = getHeight() - mListPadding.bottom; 3847 if (mFirstPosition == 0 && firstChildTop >= contentTop && 3848 mFirstPosition + childCount < mItemCount && 3849 lastChildBottom <= getHeight() - contentBottom) { 3850 mTouchMode = TOUCH_MODE_REST; 3851 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 3852 } else { 3853 final VelocityTracker velocityTracker = mVelocityTracker; 3854 velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity); 3855 3856 final int initialVelocity = (int) 3857 (velocityTracker.getYVelocity(mActivePointerId) * mVelocityScale); 3858 // Fling if we have enough velocity and we aren't at a boundary. 3859 // Since we can potentially overfling more than we can overscroll, don't 3860 // allow the weird behavior where you can scroll to a boundary then 3861 // fling further. 3862 boolean flingVelocity = Math.abs(initialVelocity) > mMinimumVelocity; 3863 if (flingVelocity && 3864 !((mFirstPosition == 0 && 3865 firstChildTop == contentTop - mOverscrollDistance) || 3866 (mFirstPosition + childCount == mItemCount && 3867 lastChildBottom == contentBottom + mOverscrollDistance))) { 3868 if (!dispatchNestedPreFling(0, -initialVelocity)) { 3869 if (mFlingRunnable == null) { 3870 mFlingRunnable = new FlingRunnable(); 3871 } 3872 reportScrollStateChange(OnScrollListener.SCROLL_STATE_FLING); 3873 mFlingRunnable.start(-initialVelocity); 3874 dispatchNestedFling(0, -initialVelocity, true); 3875 } else { 3876 mTouchMode = TOUCH_MODE_REST; 3877 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 3878 } 3879 } else { 3880 mTouchMode = TOUCH_MODE_REST; 3881 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 3882 if (mFlingRunnable != null) { 3883 mFlingRunnable.endFling(); 3884 } 3885 if (mPositionScroller != null) { 3886 mPositionScroller.stop(); 3887 } 3888 if (flingVelocity && !dispatchNestedPreFling(0, -initialVelocity)) { 3889 dispatchNestedFling(0, -initialVelocity, false); 3890 } 3891 } 3892 } 3893 } else { 3894 mTouchMode = TOUCH_MODE_REST; 3895 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 3896 } 3897 break; 3898 3899 case TOUCH_MODE_OVERSCROLL: 3900 if (mFlingRunnable == null) { 3901 mFlingRunnable = new FlingRunnable(); 3902 } 3903 final VelocityTracker velocityTracker = mVelocityTracker; 3904 velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity); 3905 final int initialVelocity = (int) velocityTracker.getYVelocity(mActivePointerId); 3906 3907 reportScrollStateChange(OnScrollListener.SCROLL_STATE_FLING); 3908 if (Math.abs(initialVelocity) > mMinimumVelocity) { 3909 mFlingRunnable.startOverfling(-initialVelocity); 3910 } else { 3911 mFlingRunnable.startSpringback(); 3912 } 3913 3914 break; 3915 } 3916 3917 setPressed(false); 3918 3919 if (mEdgeGlowTop != null) { 3920 mEdgeGlowTop.onRelease(); 3921 mEdgeGlowBottom.onRelease(); 3922 } 3923 3924 // Need to redraw since we probably aren't drawing the selector anymore 3925 invalidate(); 3926 removeCallbacks(mPendingCheckForLongPress); 3927 recycleVelocityTracker(); 3928 3929 mActivePointerId = INVALID_POINTER; 3930 3931 if (PROFILE_SCROLLING) { 3932 if (mScrollProfilingStarted) { 3933 Debug.stopMethodTracing(); 3934 mScrollProfilingStarted = false; 3935 } 3936 } 3937 3938 if (mScrollStrictSpan != null) { 3939 mScrollStrictSpan.finish(); 3940 mScrollStrictSpan = null; 3941 } 3942 } 3943 3944 private void onTouchCancel() { 3945 switch (mTouchMode) { 3946 case TOUCH_MODE_OVERSCROLL: 3947 if (mFlingRunnable == null) { 3948 mFlingRunnable = new FlingRunnable(); 3949 } 3950 mFlingRunnable.startSpringback(); 3951 break; 3952 3953 case TOUCH_MODE_OVERFLING: 3954 // Do nothing - let it play out. 3955 break; 3956 3957 default: 3958 mTouchMode = TOUCH_MODE_REST; 3959 setPressed(false); 3960 final View motionView = this.getChildAt(mMotionPosition - mFirstPosition); 3961 if (motionView != null) { 3962 motionView.setPressed(false); 3963 } 3964 clearScrollingCache(); 3965 removeCallbacks(mPendingCheckForLongPress); 3966 recycleVelocityTracker(); 3967 } 3968 3969 if (mEdgeGlowTop != null) { 3970 mEdgeGlowTop.onRelease(); 3971 mEdgeGlowBottom.onRelease(); 3972 } 3973 mActivePointerId = INVALID_POINTER; 3974 } 3975 3976 @Override 3977 protected void onOverScrolled(int scrollX, int scrollY, boolean clampedX, boolean clampedY) { 3978 if (mScrollY != scrollY) { 3979 onScrollChanged(mScrollX, scrollY, mScrollX, mScrollY); 3980 mScrollY = scrollY; 3981 invalidateParentIfNeeded(); 3982 3983 awakenScrollBars(); 3984 } 3985 } 3986 3987 @Override 3988 public boolean onGenericMotionEvent(MotionEvent event) { 3989 if ((event.getSource() & InputDevice.SOURCE_CLASS_POINTER) != 0) { 3990 switch (event.getAction()) { 3991 case MotionEvent.ACTION_SCROLL: { 3992 if (mTouchMode == TOUCH_MODE_REST) { 3993 final float vscroll = event.getAxisValue(MotionEvent.AXIS_VSCROLL); 3994 if (vscroll != 0) { 3995 final int delta = (int) (vscroll * getVerticalScrollFactor()); 3996 if (!trackMotionScroll(delta, delta)) { 3997 return true; 3998 } 3999 } 4000 } 4001 } 4002 } 4003 } 4004 return super.onGenericMotionEvent(event); 4005 } 4006 4007 /** 4008 * Initiate a fling with the given velocity. 4009 * 4010 * <p>Applications can use this method to manually initiate a fling as if the user 4011 * initiated it via touch interaction.</p> 4012 * 4013 * @param velocityY Vertical velocity in pixels per second. Note that this is velocity of 4014 * content, not velocity of a touch that initiated the fling. 4015 */ 4016 public void fling(int velocityY) { 4017 if (mFlingRunnable == null) { 4018 mFlingRunnable = new FlingRunnable(); 4019 } 4020 reportScrollStateChange(OnScrollListener.SCROLL_STATE_FLING); 4021 mFlingRunnable.start(velocityY); 4022 } 4023 4024 @Override 4025 public boolean onStartNestedScroll(View child, View target, int nestedScrollAxes) { 4026 return ((nestedScrollAxes & SCROLL_AXIS_VERTICAL) != 0); 4027 } 4028 4029 @Override 4030 public void onNestedScrollAccepted(View child, View target, int axes) { 4031 super.onNestedScrollAccepted(child, target, axes); 4032 startNestedScroll(SCROLL_AXIS_VERTICAL); 4033 } 4034 4035 @Override 4036 public void onNestedScroll(View target, int dxConsumed, int dyConsumed, 4037 int dxUnconsumed, int dyUnconsumed) { 4038 final int motionIndex = getChildCount() / 2; 4039 final View motionView = getChildAt(motionIndex); 4040 final int oldTop = motionView != null ? motionView.getTop() : 0; 4041 if (motionView == null || trackMotionScroll(-dyUnconsumed, -dyUnconsumed)) { 4042 int myUnconsumed = dyUnconsumed; 4043 int myConsumed = 0; 4044 if (motionView != null) { 4045 myConsumed = motionView.getTop() - oldTop; 4046 myUnconsumed -= myConsumed; 4047 } 4048 dispatchNestedScroll(0, myConsumed, 0, myUnconsumed, null); 4049 } 4050 } 4051 4052 @Override 4053 public boolean onNestedFling(View target, float velocityX, float velocityY, boolean consumed) { 4054 final int childCount = getChildCount(); 4055 if (!consumed && childCount > 0 && canScrollList((int) velocityY) && 4056 Math.abs(velocityY) > mMinimumVelocity) { 4057 reportScrollStateChange(OnScrollListener.SCROLL_STATE_FLING); 4058 if (mFlingRunnable == null) { 4059 mFlingRunnable = new FlingRunnable(); 4060 } 4061 if (!dispatchNestedPreFling(0, velocityY)) { 4062 mFlingRunnable.start((int) velocityY); 4063 } 4064 return true; 4065 } 4066 return dispatchNestedFling(velocityX, velocityY, consumed); 4067 } 4068 4069 @Override 4070 public void draw(Canvas canvas) { 4071 super.draw(canvas); 4072 if (mEdgeGlowTop != null) { 4073 final int scrollY = mScrollY; 4074 if (!mEdgeGlowTop.isFinished()) { 4075 final int restoreCount = canvas.save(); 4076 final int width = getWidth(); 4077 4078 int edgeY = Math.min(0, scrollY + mFirstPositionDistanceGuess); 4079 canvas.translate(0, edgeY); 4080 mEdgeGlowTop.setSize(width, getHeight()); 4081 if (mEdgeGlowTop.draw(canvas)) { 4082 invalidate(0, 0, getWidth(), 4083 mEdgeGlowTop.getMaxHeight() + getPaddingTop()); 4084 } 4085 canvas.restoreToCount(restoreCount); 4086 } 4087 if (!mEdgeGlowBottom.isFinished()) { 4088 final int restoreCount = canvas.save(); 4089 final int width = getWidth(); 4090 final int height = getHeight(); 4091 4092 int edgeX = -width; 4093 int edgeY = Math.max(height, scrollY + mLastPositionDistanceGuess); 4094 canvas.translate(edgeX, edgeY); 4095 canvas.rotate(180, width, 0); 4096 mEdgeGlowBottom.setSize(width, height); 4097 if (mEdgeGlowBottom.draw(canvas)) { 4098 invalidate(0, getHeight() - getPaddingBottom() - 4099 mEdgeGlowBottom.getMaxHeight(), getWidth(), 4100 getHeight()); 4101 } 4102 canvas.restoreToCount(restoreCount); 4103 } 4104 } 4105 } 4106 4107 /** 4108 * @hide 4109 */ 4110 public void setOverScrollEffectPadding(int leftPadding, int rightPadding) { 4111 mGlowPaddingLeft = leftPadding; 4112 mGlowPaddingRight = rightPadding; 4113 } 4114 4115 private void initOrResetVelocityTracker() { 4116 if (mVelocityTracker == null) { 4117 mVelocityTracker = VelocityTracker.obtain(); 4118 } else { 4119 mVelocityTracker.clear(); 4120 } 4121 } 4122 4123 private void initVelocityTrackerIfNotExists() { 4124 if (mVelocityTracker == null) { 4125 mVelocityTracker = VelocityTracker.obtain(); 4126 } 4127 } 4128 4129 private void recycleVelocityTracker() { 4130 if (mVelocityTracker != null) { 4131 mVelocityTracker.recycle(); 4132 mVelocityTracker = null; 4133 } 4134 } 4135 4136 @Override 4137 public void requestDisallowInterceptTouchEvent(boolean disallowIntercept) { 4138 if (disallowIntercept) { 4139 recycleVelocityTracker(); 4140 } 4141 super.requestDisallowInterceptTouchEvent(disallowIntercept); 4142 } 4143 4144 @Override 4145 public boolean onInterceptHoverEvent(MotionEvent event) { 4146 if (mFastScroll != null && mFastScroll.onInterceptHoverEvent(event)) { 4147 return true; 4148 } 4149 4150 return super.onInterceptHoverEvent(event); 4151 } 4152 4153 @Override 4154 public boolean onInterceptTouchEvent(MotionEvent ev) { 4155 int action = ev.getAction(); 4156 View v; 4157 4158 if (mPositionScroller != null) { 4159 mPositionScroller.stop(); 4160 } 4161 4162 if (mIsDetaching || !isAttachedToWindow()) { 4163 // Something isn't right. 4164 // Since we rely on being attached to get data set change notifications, 4165 // don't risk doing anything where we might try to resync and find things 4166 // in a bogus state. 4167 return false; 4168 } 4169 4170 if (mFastScroll != null && mFastScroll.onInterceptTouchEvent(ev)) { 4171 return true; 4172 } 4173 4174 switch (action & MotionEvent.ACTION_MASK) { 4175 case MotionEvent.ACTION_DOWN: { 4176 int touchMode = mTouchMode; 4177 if (touchMode == TOUCH_MODE_OVERFLING || touchMode == TOUCH_MODE_OVERSCROLL) { 4178 mMotionCorrection = 0; 4179 return true; 4180 } 4181 4182 final int x = (int) ev.getX(); 4183 final int y = (int) ev.getY(); 4184 mActivePointerId = ev.getPointerId(0); 4185 4186 int motionPosition = findMotionRow(y); 4187 if (touchMode != TOUCH_MODE_FLING && motionPosition >= 0) { 4188 // User clicked on an actual view (and was not stopping a fling). 4189 // Remember where the motion event started 4190 v = getChildAt(motionPosition - mFirstPosition); 4191 mMotionViewOriginalTop = v.getTop(); 4192 mMotionX = x; 4193 mMotionY = y; 4194 mMotionPosition = motionPosition; 4195 mTouchMode = TOUCH_MODE_DOWN; 4196 clearScrollingCache(); 4197 } 4198 mLastY = Integer.MIN_VALUE; 4199 initOrResetVelocityTracker(); 4200 mVelocityTracker.addMovement(ev); 4201 startNestedScroll(SCROLL_AXIS_VERTICAL); 4202 if (touchMode == TOUCH_MODE_FLING) { 4203 return true; 4204 } 4205 break; 4206 } 4207 4208 case MotionEvent.ACTION_MOVE: { 4209 switch (mTouchMode) { 4210 case TOUCH_MODE_DOWN: 4211 int pointerIndex = ev.findPointerIndex(mActivePointerId); 4212 if (pointerIndex == -1) { 4213 pointerIndex = 0; 4214 mActivePointerId = ev.getPointerId(pointerIndex); 4215 } 4216 final int y = (int) ev.getY(pointerIndex); 4217 initVelocityTrackerIfNotExists(); 4218 mVelocityTracker.addMovement(ev); 4219 if (startScrollIfNeeded((int) ev.getX(pointerIndex), y, null)) { 4220 return true; 4221 } 4222 break; 4223 } 4224 break; 4225 } 4226 4227 case MotionEvent.ACTION_CANCEL: 4228 case MotionEvent.ACTION_UP: { 4229 mTouchMode = TOUCH_MODE_REST; 4230 mActivePointerId = INVALID_POINTER; 4231 recycleVelocityTracker(); 4232 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 4233 stopNestedScroll(); 4234 break; 4235 } 4236 4237 case MotionEvent.ACTION_POINTER_UP: { 4238 onSecondaryPointerUp(ev); 4239 break; 4240 } 4241 } 4242 4243 return false; 4244 } 4245 4246 private void onSecondaryPointerUp(MotionEvent ev) { 4247 final int pointerIndex = (ev.getAction() & MotionEvent.ACTION_POINTER_INDEX_MASK) >> 4248 MotionEvent.ACTION_POINTER_INDEX_SHIFT; 4249 final int pointerId = ev.getPointerId(pointerIndex); 4250 if (pointerId == mActivePointerId) { 4251 // This was our active pointer going up. Choose a new 4252 // active pointer and adjust accordingly. 4253 // TODO: Make this decision more intelligent. 4254 final int newPointerIndex = pointerIndex == 0 ? 1 : 0; 4255 mMotionX = (int) ev.getX(newPointerIndex); 4256 mMotionY = (int) ev.getY(newPointerIndex); 4257 mMotionCorrection = 0; 4258 mActivePointerId = ev.getPointerId(newPointerIndex); 4259 } 4260 } 4261 4262 /** 4263 * {@inheritDoc} 4264 */ 4265 @Override 4266 public void addTouchables(ArrayList<View> views) { 4267 final int count = getChildCount(); 4268 final int firstPosition = mFirstPosition; 4269 final ListAdapter adapter = mAdapter; 4270 4271 if (adapter == null) { 4272 return; 4273 } 4274 4275 for (int i = 0; i < count; i++) { 4276 final View child = getChildAt(i); 4277 if (adapter.isEnabled(firstPosition + i)) { 4278 views.add(child); 4279 } 4280 child.addTouchables(views); 4281 } 4282 } 4283 4284 /** 4285 * Fires an "on scroll state changed" event to the registered 4286 * {@link android.widget.AbsListView.OnScrollListener}, if any. The state change 4287 * is fired only if the specified state is different from the previously known state. 4288 * 4289 * @param newState The new scroll state. 4290 */ 4291 void reportScrollStateChange(int newState) { 4292 if (newState != mLastScrollState) { 4293 if (mOnScrollListener != null) { 4294 mLastScrollState = newState; 4295 mOnScrollListener.onScrollStateChanged(this, newState); 4296 } 4297 } 4298 } 4299 4300 /** 4301 * Responsible for fling behavior. Use {@link #start(int)} to 4302 * initiate a fling. Each frame of the fling is handled in {@link #run()}. 4303 * A FlingRunnable will keep re-posting itself until the fling is done. 4304 * 4305 */ 4306 private class FlingRunnable implements Runnable { 4307 /** 4308 * Tracks the decay of a fling scroll 4309 */ 4310 private final OverScroller mScroller; 4311 4312 /** 4313 * Y value reported by mScroller on the previous fling 4314 */ 4315 private int mLastFlingY; 4316 4317 private final Runnable mCheckFlywheel = new Runnable() { 4318 @Override 4319 public void run() { 4320 final int activeId = mActivePointerId; 4321 final VelocityTracker vt = mVelocityTracker; 4322 final OverScroller scroller = mScroller; 4323 if (vt == null || activeId == INVALID_POINTER) { 4324 return; 4325 } 4326 4327 vt.computeCurrentVelocity(1000, mMaximumVelocity); 4328 final float yvel = -vt.getYVelocity(activeId); 4329 4330 if (Math.abs(yvel) >= mMinimumVelocity 4331 && scroller.isScrollingInDirection(0, yvel)) { 4332 // Keep the fling alive a little longer 4333 postDelayed(this, FLYWHEEL_TIMEOUT); 4334 } else { 4335 endFling(); 4336 mTouchMode = TOUCH_MODE_SCROLL; 4337 reportScrollStateChange(OnScrollListener.SCROLL_STATE_TOUCH_SCROLL); 4338 } 4339 } 4340 }; 4341 4342 private static final int FLYWHEEL_TIMEOUT = 40; // milliseconds 4343 4344 FlingRunnable() { 4345 mScroller = new OverScroller(getContext()); 4346 } 4347 4348 void start(int initialVelocity) { 4349 int initialY = initialVelocity < 0 ? Integer.MAX_VALUE : 0; 4350 mLastFlingY = initialY; 4351 mScroller.setInterpolator(null); 4352 mScroller.fling(0, initialY, 0, initialVelocity, 4353 0, Integer.MAX_VALUE, 0, Integer.MAX_VALUE); 4354 mTouchMode = TOUCH_MODE_FLING; 4355 postOnAnimation(this); 4356 4357 if (PROFILE_FLINGING) { 4358 if (!mFlingProfilingStarted) { 4359 Debug.startMethodTracing("AbsListViewFling"); 4360 mFlingProfilingStarted = true; 4361 } 4362 } 4363 4364 if (mFlingStrictSpan == null) { 4365 mFlingStrictSpan = StrictMode.enterCriticalSpan("AbsListView-fling"); 4366 } 4367 } 4368 4369 void startSpringback() { 4370 if (mScroller.springBack(0, mScrollY, 0, 0, 0, 0)) { 4371 mTouchMode = TOUCH_MODE_OVERFLING; 4372 invalidate(); 4373 postOnAnimation(this); 4374 } else { 4375 mTouchMode = TOUCH_MODE_REST; 4376 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 4377 } 4378 } 4379 4380 void startOverfling(int initialVelocity) { 4381 mScroller.setInterpolator(null); 4382 mScroller.fling(0, mScrollY, 0, initialVelocity, 0, 0, 4383 Integer.MIN_VALUE, Integer.MAX_VALUE, 0, getHeight()); 4384 mTouchMode = TOUCH_MODE_OVERFLING; 4385 invalidate(); 4386 postOnAnimation(this); 4387 } 4388 4389 void edgeReached(int delta) { 4390 mScroller.notifyVerticalEdgeReached(mScrollY, 0, mOverflingDistance); 4391 final int overscrollMode = getOverScrollMode(); 4392 if (overscrollMode == OVER_SCROLL_ALWAYS || 4393 (overscrollMode == OVER_SCROLL_IF_CONTENT_SCROLLS && !contentFits())) { 4394 mTouchMode = TOUCH_MODE_OVERFLING; 4395 final int vel = (int) mScroller.getCurrVelocity(); 4396 if (delta > 0) { 4397 mEdgeGlowTop.onAbsorb(vel); 4398 } else { 4399 mEdgeGlowBottom.onAbsorb(vel); 4400 } 4401 } else { 4402 mTouchMode = TOUCH_MODE_REST; 4403 if (mPositionScroller != null) { 4404 mPositionScroller.stop(); 4405 } 4406 } 4407 invalidate(); 4408 postOnAnimation(this); 4409 } 4410 4411 void startScroll(int distance, int duration, boolean linear) { 4412 int initialY = distance < 0 ? Integer.MAX_VALUE : 0; 4413 mLastFlingY = initialY; 4414 mScroller.setInterpolator(linear ? sLinearInterpolator : null); 4415 mScroller.startScroll(0, initialY, 0, distance, duration); 4416 mTouchMode = TOUCH_MODE_FLING; 4417 postOnAnimation(this); 4418 } 4419 4420 void endFling() { 4421 mTouchMode = TOUCH_MODE_REST; 4422 4423 removeCallbacks(this); 4424 removeCallbacks(mCheckFlywheel); 4425 4426 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 4427 clearScrollingCache(); 4428 mScroller.abortAnimation(); 4429 4430 if (mFlingStrictSpan != null) { 4431 mFlingStrictSpan.finish(); 4432 mFlingStrictSpan = null; 4433 } 4434 } 4435 4436 void flywheelTouch() { 4437 postDelayed(mCheckFlywheel, FLYWHEEL_TIMEOUT); 4438 } 4439 4440 @Override 4441 public void run() { 4442 switch (mTouchMode) { 4443 default: 4444 endFling(); 4445 return; 4446 4447 case TOUCH_MODE_SCROLL: 4448 if (mScroller.isFinished()) { 4449 return; 4450 } 4451 // Fall through 4452 case TOUCH_MODE_FLING: { 4453 if (mDataChanged) { 4454 layoutChildren(); 4455 } 4456 4457 if (mItemCount == 0 || getChildCount() == 0) { 4458 endFling(); 4459 return; 4460 } 4461 4462 final OverScroller scroller = mScroller; 4463 boolean more = scroller.computeScrollOffset(); 4464 final int y = scroller.getCurrY(); 4465 4466 // Flip sign to convert finger direction to list items direction 4467 // (e.g. finger moving down means list is moving towards the top) 4468 int delta = mLastFlingY - y; 4469 4470 // Pretend that each frame of a fling scroll is a touch scroll 4471 if (delta > 0) { 4472 // List is moving towards the top. Use first view as mMotionPosition 4473 mMotionPosition = mFirstPosition; 4474 final View firstView = getChildAt(0); 4475 mMotionViewOriginalTop = firstView.getTop(); 4476 4477 // Don't fling more than 1 screen 4478 delta = Math.min(getHeight() - mPaddingBottom - mPaddingTop - 1, delta); 4479 } else { 4480 // List is moving towards the bottom. Use last view as mMotionPosition 4481 int offsetToLast = getChildCount() - 1; 4482 mMotionPosition = mFirstPosition + offsetToLast; 4483 4484 final View lastView = getChildAt(offsetToLast); 4485 mMotionViewOriginalTop = lastView.getTop(); 4486 4487 // Don't fling more than 1 screen 4488 delta = Math.max(-(getHeight() - mPaddingBottom - mPaddingTop - 1), delta); 4489 } 4490 4491 // Check to see if we have bumped into the scroll limit 4492 View motionView = getChildAt(mMotionPosition - mFirstPosition); 4493 int oldTop = 0; 4494 if (motionView != null) { 4495 oldTop = motionView.getTop(); 4496 } 4497 4498 // Don't stop just because delta is zero (it could have been rounded) 4499 final boolean atEdge = trackMotionScroll(delta, delta); 4500 final boolean atEnd = atEdge && (delta != 0); 4501 if (atEnd) { 4502 if (motionView != null) { 4503 // Tweak the scroll for how far we overshot 4504 int overshoot = -(delta - (motionView.getTop() - oldTop)); 4505 overScrollBy(0, overshoot, 0, mScrollY, 0, 0, 4506 0, mOverflingDistance, false); 4507 } 4508 if (more) { 4509 edgeReached(delta); 4510 } 4511 break; 4512 } 4513 4514 if (more && !atEnd) { 4515 if (atEdge) invalidate(); 4516 mLastFlingY = y; 4517 postOnAnimation(this); 4518 } else { 4519 endFling(); 4520 4521 if (PROFILE_FLINGING) { 4522 if (mFlingProfilingStarted) { 4523 Debug.stopMethodTracing(); 4524 mFlingProfilingStarted = false; 4525 } 4526 4527 if (mFlingStrictSpan != null) { 4528 mFlingStrictSpan.finish(); 4529 mFlingStrictSpan = null; 4530 } 4531 } 4532 } 4533 break; 4534 } 4535 4536 case TOUCH_MODE_OVERFLING: { 4537 final OverScroller scroller = mScroller; 4538 if (scroller.computeScrollOffset()) { 4539 final int scrollY = mScrollY; 4540 final int currY = scroller.getCurrY(); 4541 final int deltaY = currY - scrollY; 4542 if (overScrollBy(0, deltaY, 0, scrollY, 0, 0, 4543 0, mOverflingDistance, false)) { 4544 final boolean crossDown = scrollY <= 0 && currY > 0; 4545 final boolean crossUp = scrollY >= 0 && currY < 0; 4546 if (crossDown || crossUp) { 4547 int velocity = (int) scroller.getCurrVelocity(); 4548 if (crossUp) velocity = -velocity; 4549 4550 // Don't flywheel from this; we're just continuing things. 4551 scroller.abortAnimation(); 4552 start(velocity); 4553 } else { 4554 startSpringback(); 4555 } 4556 } else { 4557 invalidate(); 4558 postOnAnimation(this); 4559 } 4560 } else { 4561 endFling(); 4562 } 4563 break; 4564 } 4565 } 4566 } 4567 } 4568 4569 /** 4570 * The amount of friction applied to flings. The default value 4571 * is {@link ViewConfiguration#getScrollFriction}. 4572 */ 4573 public void setFriction(float friction) { 4574 if (mFlingRunnable == null) { 4575 mFlingRunnable = new FlingRunnable(); 4576 } 4577 mFlingRunnable.mScroller.setFriction(friction); 4578 } 4579 4580 /** 4581 * Sets a scale factor for the fling velocity. The initial scale 4582 * factor is 1.0. 4583 * 4584 * @param scale The scale factor to multiply the velocity by. 4585 */ 4586 public void setVelocityScale(float scale) { 4587 mVelocityScale = scale; 4588 } 4589 4590 /** 4591 * Override this for better control over position scrolling. 4592 */ 4593 AbsPositionScroller createPositionScroller() { 4594 return new PositionScroller(); 4595 } 4596 4597 /** 4598 * Smoothly scroll to the specified adapter position. The view will 4599 * scroll such that the indicated position is displayed. 4600 * @param position Scroll to this adapter position. 4601 */ 4602 public void smoothScrollToPosition(int position) { 4603 if (mPositionScroller == null) { 4604 mPositionScroller = createPositionScroller(); 4605 } 4606 mPositionScroller.start(position); 4607 } 4608 4609 /** 4610 * Smoothly scroll to the specified adapter position. The view will scroll 4611 * such that the indicated position is displayed <code>offset</code> pixels below 4612 * the top edge of the view. If this is impossible, (e.g. the offset would scroll 4613 * the first or last item beyond the boundaries of the list) it will get as close 4614 * as possible. The scroll will take <code>duration</code> milliseconds to complete. 4615 * 4616 * @param position Position to scroll to 4617 * @param offset Desired distance in pixels of <code>position</code> from the top 4618 * of the view when scrolling is finished 4619 * @param duration Number of milliseconds to use for the scroll 4620 */ 4621 public void smoothScrollToPositionFromTop(int position, int offset, int duration) { 4622 if (mPositionScroller == null) { 4623 mPositionScroller = createPositionScroller(); 4624 } 4625 mPositionScroller.startWithOffset(position, offset, duration); 4626 } 4627 4628 /** 4629 * Smoothly scroll to the specified adapter position. The view will scroll 4630 * such that the indicated position is displayed <code>offset</code> pixels below 4631 * the top edge of the view. If this is impossible, (e.g. the offset would scroll 4632 * the first or last item beyond the boundaries of the list) it will get as close 4633 * as possible. 4634 * 4635 * @param position Position to scroll to 4636 * @param offset Desired distance in pixels of <code>position</code> from the top 4637 * of the view when scrolling is finished 4638 */ 4639 public void smoothScrollToPositionFromTop(int position, int offset) { 4640 if (mPositionScroller == null) { 4641 mPositionScroller = createPositionScroller(); 4642 } 4643 mPositionScroller.startWithOffset(position, offset, offset); 4644 } 4645 4646 /** 4647 * Smoothly scroll to the specified adapter position. The view will 4648 * scroll such that the indicated position is displayed, but it will 4649 * stop early if scrolling further would scroll boundPosition out of 4650 * view. 4651 * 4652 * @param position Scroll to this adapter position. 4653 * @param boundPosition Do not scroll if it would move this adapter 4654 * position out of view. 4655 */ 4656 public void smoothScrollToPosition(int position, int boundPosition) { 4657 if (mPositionScroller == null) { 4658 mPositionScroller = createPositionScroller(); 4659 } 4660 mPositionScroller.start(position, boundPosition); 4661 } 4662 4663 /** 4664 * Smoothly scroll by distance pixels over duration milliseconds. 4665 * @param distance Distance to scroll in pixels. 4666 * @param duration Duration of the scroll animation in milliseconds. 4667 */ 4668 public void smoothScrollBy(int distance, int duration) { 4669 smoothScrollBy(distance, duration, false); 4670 } 4671 4672 void smoothScrollBy(int distance, int duration, boolean linear) { 4673 if (mFlingRunnable == null) { 4674 mFlingRunnable = new FlingRunnable(); 4675 } 4676 4677 // No sense starting to scroll if we're not going anywhere 4678 final int firstPos = mFirstPosition; 4679 final int childCount = getChildCount(); 4680 final int lastPos = firstPos + childCount; 4681 final int topLimit = getPaddingTop(); 4682 final int bottomLimit = getHeight() - getPaddingBottom(); 4683 4684 if (distance == 0 || mItemCount == 0 || childCount == 0 || 4685 (firstPos == 0 && getChildAt(0).getTop() == topLimit && distance < 0) || 4686 (lastPos == mItemCount && 4687 getChildAt(childCount - 1).getBottom() == bottomLimit && distance > 0)) { 4688 mFlingRunnable.endFling(); 4689 if (mPositionScroller != null) { 4690 mPositionScroller.stop(); 4691 } 4692 } else { 4693 reportScrollStateChange(OnScrollListener.SCROLL_STATE_FLING); 4694 mFlingRunnable.startScroll(distance, duration, linear); 4695 } 4696 } 4697 4698 /** 4699 * Allows RemoteViews to scroll relatively to a position. 4700 */ 4701 void smoothScrollByOffset(int position) { 4702 int index = -1; 4703 if (position < 0) { 4704 index = getFirstVisiblePosition(); 4705 } else if (position > 0) { 4706 index = getLastVisiblePosition(); 4707 } 4708 4709 if (index > -1) { 4710 View child = getChildAt(index - getFirstVisiblePosition()); 4711 if (child != null) { 4712 Rect visibleRect = new Rect(); 4713 if (child.getGlobalVisibleRect(visibleRect)) { 4714 // the child is partially visible 4715 int childRectArea = child.getWidth() * child.getHeight(); 4716 int visibleRectArea = visibleRect.width() * visibleRect.height(); 4717 float visibleArea = (visibleRectArea / (float) childRectArea); 4718 final float visibleThreshold = 0.75f; 4719 if ((position < 0) && (visibleArea < visibleThreshold)) { 4720 // the top index is not perceivably visible so offset 4721 // to account for showing that top index as well 4722 ++index; 4723 } else if ((position > 0) && (visibleArea < visibleThreshold)) { 4724 // the bottom index is not perceivably visible so offset 4725 // to account for showing that bottom index as well 4726 --index; 4727 } 4728 } 4729 smoothScrollToPosition(Math.max(0, Math.min(getCount(), index + position))); 4730 } 4731 } 4732 } 4733 4734 private void createScrollingCache() { 4735 if (mScrollingCacheEnabled && !mCachingStarted && !isHardwareAccelerated()) { 4736 setChildrenDrawnWithCacheEnabled(true); 4737 setChildrenDrawingCacheEnabled(true); 4738 mCachingStarted = mCachingActive = true; 4739 } 4740 } 4741 4742 private void clearScrollingCache() { 4743 if (!isHardwareAccelerated()) { 4744 if (mClearScrollingCache == null) { 4745 mClearScrollingCache = new Runnable() { 4746 @Override 4747 public void run() { 4748 if (mCachingStarted) { 4749 mCachingStarted = mCachingActive = false; 4750 setChildrenDrawnWithCacheEnabled(false); 4751 if ((mPersistentDrawingCache & PERSISTENT_SCROLLING_CACHE) == 0) { 4752 setChildrenDrawingCacheEnabled(false); 4753 } 4754 if (!isAlwaysDrawnWithCacheEnabled()) { 4755 invalidate(); 4756 } 4757 } 4758 } 4759 }; 4760 } 4761 post(mClearScrollingCache); 4762 } 4763 } 4764 4765 /** 4766 * Scrolls the list items within the view by a specified number of pixels. 4767 * 4768 * @param y the amount of pixels to scroll by vertically 4769 * @see #canScrollList(int) 4770 */ 4771 public void scrollListBy(int y) { 4772 trackMotionScroll(-y, -y); 4773 } 4774 4775 /** 4776 * Check if the items in the list can be scrolled in a certain direction. 4777 * 4778 * @param direction Negative to check scrolling up, positive to check 4779 * scrolling down. 4780 * @return true if the list can be scrolled in the specified direction, 4781 * false otherwise. 4782 * @see #scrollListBy(int) 4783 */ 4784 public boolean canScrollList(int direction) { 4785 final int childCount = getChildCount(); 4786 if (childCount == 0) { 4787 return false; 4788 } 4789 4790 final int firstPosition = mFirstPosition; 4791 final Rect listPadding = mListPadding; 4792 if (direction > 0) { 4793 final int lastBottom = getChildAt(childCount - 1).getBottom(); 4794 final int lastPosition = firstPosition + childCount; 4795 return lastPosition < mItemCount || lastBottom > getHeight() - listPadding.bottom; 4796 } else { 4797 final int firstTop = getChildAt(0).getTop(); 4798 return firstPosition > 0 || firstTop < listPadding.top; 4799 } 4800 } 4801 4802 /** 4803 * Track a motion scroll 4804 * 4805 * @param deltaY Amount to offset mMotionView. This is the accumulated delta since the motion 4806 * began. Positive numbers mean the user's finger is moving down the screen. 4807 * @param incrementalDeltaY Change in deltaY from the previous event. 4808 * @return true if we're already at the beginning/end of the list and have nothing to do. 4809 */ 4810 boolean trackMotionScroll(int deltaY, int incrementalDeltaY) { 4811 final int childCount = getChildCount(); 4812 if (childCount == 0) { 4813 return true; 4814 } 4815 4816 final int firstTop = getChildAt(0).getTop(); 4817 final int lastBottom = getChildAt(childCount - 1).getBottom(); 4818 4819 final Rect listPadding = mListPadding; 4820 4821 // "effective padding" In this case is the amount of padding that affects 4822 // how much space should not be filled by items. If we don't clip to padding 4823 // there is no effective padding. 4824 int effectivePaddingTop = 0; 4825 int effectivePaddingBottom = 0; 4826 if ((mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK) { 4827 effectivePaddingTop = listPadding.top; 4828 effectivePaddingBottom = listPadding.bottom; 4829 } 4830 4831 // FIXME account for grid vertical spacing too? 4832 final int spaceAbove = effectivePaddingTop - firstTop; 4833 final int end = getHeight() - effectivePaddingBottom; 4834 final int spaceBelow = lastBottom - end; 4835 4836 final int height = getHeight() - mPaddingBottom - mPaddingTop; 4837 if (deltaY < 0) { 4838 deltaY = Math.max(-(height - 1), deltaY); 4839 } else { 4840 deltaY = Math.min(height - 1, deltaY); 4841 } 4842 4843 if (incrementalDeltaY < 0) { 4844 incrementalDeltaY = Math.max(-(height - 1), incrementalDeltaY); 4845 } else { 4846 incrementalDeltaY = Math.min(height - 1, incrementalDeltaY); 4847 } 4848 4849 final int firstPosition = mFirstPosition; 4850 4851 // Update our guesses for where the first and last views are 4852 if (firstPosition == 0) { 4853 mFirstPositionDistanceGuess = firstTop - listPadding.top; 4854 } else { 4855 mFirstPositionDistanceGuess += incrementalDeltaY; 4856 } 4857 if (firstPosition + childCount == mItemCount) { 4858 mLastPositionDistanceGuess = lastBottom + listPadding.bottom; 4859 } else { 4860 mLastPositionDistanceGuess += incrementalDeltaY; 4861 } 4862 4863 final boolean cannotScrollDown = (firstPosition == 0 && 4864 firstTop >= listPadding.top && incrementalDeltaY >= 0); 4865 final boolean cannotScrollUp = (firstPosition + childCount == mItemCount && 4866 lastBottom <= getHeight() - listPadding.bottom && incrementalDeltaY <= 0); 4867 4868 if (cannotScrollDown || cannotScrollUp) { 4869 return incrementalDeltaY != 0; 4870 } 4871 4872 final boolean down = incrementalDeltaY < 0; 4873 4874 final boolean inTouchMode = isInTouchMode(); 4875 if (inTouchMode) { 4876 hideSelector(); 4877 } 4878 4879 final int headerViewsCount = getHeaderViewsCount(); 4880 final int footerViewsStart = mItemCount - getFooterViewsCount(); 4881 4882 int start = 0; 4883 int count = 0; 4884 4885 if (down) { 4886 int top = -incrementalDeltaY; 4887 if ((mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK) { 4888 top += listPadding.top; 4889 } 4890 for (int i = 0; i < childCount; i++) { 4891 final View child = getChildAt(i); 4892 if (child.getBottom() >= top) { 4893 break; 4894 } else { 4895 count++; 4896 int position = firstPosition + i; 4897 if (position >= headerViewsCount && position < footerViewsStart) { 4898 // The view will be rebound to new data, clear any 4899 // system-managed transient state. 4900 if (child.isAccessibilityFocused()) { 4901 child.clearAccessibilityFocus(); 4902 } 4903 mRecycler.addScrapView(child, position); 4904 } 4905 } 4906 } 4907 } else { 4908 int bottom = getHeight() - incrementalDeltaY; 4909 if ((mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK) { 4910 bottom -= listPadding.bottom; 4911 } 4912 for (int i = childCount - 1; i >= 0; i--) { 4913 final View child = getChildAt(i); 4914 if (child.getTop() <= bottom) { 4915 break; 4916 } else { 4917 start = i; 4918 count++; 4919 int position = firstPosition + i; 4920 if (position >= headerViewsCount && position < footerViewsStart) { 4921 // The view will be rebound to new data, clear any 4922 // system-managed transient state. 4923 if (child.isAccessibilityFocused()) { 4924 child.clearAccessibilityFocus(); 4925 } 4926 mRecycler.addScrapView(child, position); 4927 } 4928 } 4929 } 4930 } 4931 4932 mMotionViewNewTop = mMotionViewOriginalTop + deltaY; 4933 4934 mBlockLayoutRequests = true; 4935 4936 if (count > 0) { 4937 detachViewsFromParent(start, count); 4938 mRecycler.removeSkippedScrap(); 4939 } 4940 4941 // invalidate before moving the children to avoid unnecessary invalidate 4942 // calls to bubble up from the children all the way to the top 4943 if (!awakenScrollBars()) { 4944 invalidate(); 4945 } 4946 4947 offsetChildrenTopAndBottom(incrementalDeltaY); 4948 4949 if (down) { 4950 mFirstPosition += count; 4951 } 4952 4953 final int absIncrementalDeltaY = Math.abs(incrementalDeltaY); 4954 if (spaceAbove < absIncrementalDeltaY || spaceBelow < absIncrementalDeltaY) { 4955 fillGap(down); 4956 } 4957 4958 if (!inTouchMode && mSelectedPosition != INVALID_POSITION) { 4959 final int childIndex = mSelectedPosition - mFirstPosition; 4960 if (childIndex >= 0 && childIndex < getChildCount()) { 4961 positionSelector(mSelectedPosition, getChildAt(childIndex)); 4962 } 4963 } else if (mSelectorPosition != INVALID_POSITION) { 4964 final int childIndex = mSelectorPosition - mFirstPosition; 4965 if (childIndex >= 0 && childIndex < getChildCount()) { 4966 positionSelector(INVALID_POSITION, getChildAt(childIndex)); 4967 } 4968 } else { 4969 mSelectorRect.setEmpty(); 4970 } 4971 4972 mBlockLayoutRequests = false; 4973 4974 invokeOnItemScrollListener(); 4975 4976 return false; 4977 } 4978 4979 /** 4980 * Returns the number of header views in the list. Header views are special views 4981 * at the top of the list that should not be recycled during a layout. 4982 * 4983 * @return The number of header views, 0 in the default implementation. 4984 */ 4985 int getHeaderViewsCount() { 4986 return 0; 4987 } 4988 4989 /** 4990 * Returns the number of footer views in the list. Footer views are special views 4991 * at the bottom of the list that should not be recycled during a layout. 4992 * 4993 * @return The number of footer views, 0 in the default implementation. 4994 */ 4995 int getFooterViewsCount() { 4996 return 0; 4997 } 4998 4999 /** 5000 * Fills the gap left open by a touch-scroll. During a touch scroll, children that 5001 * remain on screen are shifted and the other ones are discarded. The role of this 5002 * method is to fill the gap thus created by performing a partial layout in the 5003 * empty space. 5004 * 5005 * @param down true if the scroll is going down, false if it is going up 5006 */ 5007 abstract void fillGap(boolean down); 5008 5009 void hideSelector() { 5010 if (mSelectedPosition != INVALID_POSITION) { 5011 if (mLayoutMode != LAYOUT_SPECIFIC) { 5012 mResurrectToPosition = mSelectedPosition; 5013 } 5014 if (mNextSelectedPosition >= 0 && mNextSelectedPosition != mSelectedPosition) { 5015 mResurrectToPosition = mNextSelectedPosition; 5016 } 5017 setSelectedPositionInt(INVALID_POSITION); 5018 setNextSelectedPositionInt(INVALID_POSITION); 5019 mSelectedTop = 0; 5020 } 5021 } 5022 5023 /** 5024 * @return A position to select. First we try mSelectedPosition. If that has been clobbered by 5025 * entering touch mode, we then try mResurrectToPosition. Values are pinned to the range 5026 * of items available in the adapter 5027 */ 5028 int reconcileSelectedPosition() { 5029 int position = mSelectedPosition; 5030 if (position < 0) { 5031 position = mResurrectToPosition; 5032 } 5033 position = Math.max(0, position); 5034 position = Math.min(position, mItemCount - 1); 5035 return position; 5036 } 5037 5038 /** 5039 * Find the row closest to y. This row will be used as the motion row when scrolling 5040 * 5041 * @param y Where the user touched 5042 * @return The position of the first (or only) item in the row containing y 5043 */ 5044 abstract int findMotionRow(int y); 5045 5046 /** 5047 * Find the row closest to y. This row will be used as the motion row when scrolling. 5048 * 5049 * @param y Where the user touched 5050 * @return The position of the first (or only) item in the row closest to y 5051 */ 5052 int findClosestMotionRow(int y) { 5053 final int childCount = getChildCount(); 5054 if (childCount == 0) { 5055 return INVALID_POSITION; 5056 } 5057 5058 final int motionRow = findMotionRow(y); 5059 return motionRow != INVALID_POSITION ? motionRow : mFirstPosition + childCount - 1; 5060 } 5061 5062 /** 5063 * Causes all the views to be rebuilt and redrawn. 5064 */ 5065 public void invalidateViews() { 5066 mDataChanged = true; 5067 rememberSyncState(); 5068 requestLayout(); 5069 invalidate(); 5070 } 5071 5072 /** 5073 * If there is a selection returns false. 5074 * Otherwise resurrects the selection and returns true if resurrected. 5075 */ 5076 boolean resurrectSelectionIfNeeded() { 5077 if (mSelectedPosition < 0 && resurrectSelection()) { 5078 updateSelectorState(); 5079 return true; 5080 } 5081 return false; 5082 } 5083 5084 /** 5085 * Makes the item at the supplied position selected. 5086 * 5087 * @param position the position of the new selection 5088 */ 5089 abstract void setSelectionInt(int position); 5090 5091 /** 5092 * Attempt to bring the selection back if the user is switching from touch 5093 * to trackball mode 5094 * @return Whether selection was set to something. 5095 */ 5096 boolean resurrectSelection() { 5097 final int childCount = getChildCount(); 5098 5099 if (childCount <= 0) { 5100 return false; 5101 } 5102 5103 int selectedTop = 0; 5104 int selectedPos; 5105 int childrenTop = mListPadding.top; 5106 int childrenBottom = mBottom - mTop - mListPadding.bottom; 5107 final int firstPosition = mFirstPosition; 5108 final int toPosition = mResurrectToPosition; 5109 boolean down = true; 5110 5111 if (toPosition >= firstPosition && toPosition < firstPosition + childCount) { 5112 selectedPos = toPosition; 5113 5114 final View selected = getChildAt(selectedPos - mFirstPosition); 5115 selectedTop = selected.getTop(); 5116 int selectedBottom = selected.getBottom(); 5117 5118 // We are scrolled, don't get in the fade 5119 if (selectedTop < childrenTop) { 5120 selectedTop = childrenTop + getVerticalFadingEdgeLength(); 5121 } else if (selectedBottom > childrenBottom) { 5122 selectedTop = childrenBottom - selected.getMeasuredHeight() 5123 - getVerticalFadingEdgeLength(); 5124 } 5125 } else { 5126 if (toPosition < firstPosition) { 5127 // Default to selecting whatever is first 5128 selectedPos = firstPosition; 5129 for (int i = 0; i < childCount; i++) { 5130 final View v = getChildAt(i); 5131 final int top = v.getTop(); 5132 5133 if (i == 0) { 5134 // Remember the position of the first item 5135 selectedTop = top; 5136 // See if we are scrolled at all 5137 if (firstPosition > 0 || top < childrenTop) { 5138 // If we are scrolled, don't select anything that is 5139 // in the fade region 5140 childrenTop += getVerticalFadingEdgeLength(); 5141 } 5142 } 5143 if (top >= childrenTop) { 5144 // Found a view whose top is fully visisble 5145 selectedPos = firstPosition + i; 5146 selectedTop = top; 5147 break; 5148 } 5149 } 5150 } else { 5151 final int itemCount = mItemCount; 5152 down = false; 5153 selectedPos = firstPosition + childCount - 1; 5154 5155 for (int i = childCount - 1; i >= 0; i--) { 5156 final View v = getChildAt(i); 5157 final int top = v.getTop(); 5158 final int bottom = v.getBottom(); 5159 5160 if (i == childCount - 1) { 5161 selectedTop = top; 5162 if (firstPosition + childCount < itemCount || bottom > childrenBottom) { 5163 childrenBottom -= getVerticalFadingEdgeLength(); 5164 } 5165 } 5166 5167 if (bottom <= childrenBottom) { 5168 selectedPos = firstPosition + i; 5169 selectedTop = top; 5170 break; 5171 } 5172 } 5173 } 5174 } 5175 5176 mResurrectToPosition = INVALID_POSITION; 5177 removeCallbacks(mFlingRunnable); 5178 if (mPositionScroller != null) { 5179 mPositionScroller.stop(); 5180 } 5181 mTouchMode = TOUCH_MODE_REST; 5182 clearScrollingCache(); 5183 mSpecificTop = selectedTop; 5184 selectedPos = lookForSelectablePosition(selectedPos, down); 5185 if (selectedPos >= firstPosition && selectedPos <= getLastVisiblePosition()) { 5186 mLayoutMode = LAYOUT_SPECIFIC; 5187 updateSelectorState(); 5188 setSelectionInt(selectedPos); 5189 invokeOnItemScrollListener(); 5190 } else { 5191 selectedPos = INVALID_POSITION; 5192 } 5193 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 5194 5195 return selectedPos >= 0; 5196 } 5197 5198 void confirmCheckedPositionsById() { 5199 // Clear out the positional check states, we'll rebuild it below from IDs. 5200 mCheckStates.clear(); 5201 5202 boolean checkedCountChanged = false; 5203 for (int checkedIndex = 0; checkedIndex < mCheckedIdStates.size(); checkedIndex++) { 5204 final long id = mCheckedIdStates.keyAt(checkedIndex); 5205 final int lastPos = mCheckedIdStates.valueAt(checkedIndex); 5206 5207 final long lastPosId = mAdapter.getItemId(lastPos); 5208 if (id != lastPosId) { 5209 // Look around to see if the ID is nearby. If not, uncheck it. 5210 final int start = Math.max(0, lastPos - CHECK_POSITION_SEARCH_DISTANCE); 5211 final int end = Math.min(lastPos + CHECK_POSITION_SEARCH_DISTANCE, mItemCount); 5212 boolean found = false; 5213 for (int searchPos = start; searchPos < end; searchPos++) { 5214 final long searchId = mAdapter.getItemId(searchPos); 5215 if (id == searchId) { 5216 found = true; 5217 mCheckStates.put(searchPos, true); 5218 mCheckedIdStates.setValueAt(checkedIndex, searchPos); 5219 break; 5220 } 5221 } 5222 5223 if (!found) { 5224 mCheckedIdStates.delete(id); 5225 checkedIndex--; 5226 mCheckedItemCount--; 5227 checkedCountChanged = true; 5228 if (mChoiceActionMode != null && mMultiChoiceModeCallback != null) { 5229 mMultiChoiceModeCallback.onItemCheckedStateChanged(mChoiceActionMode, 5230 lastPos, id, false); 5231 } 5232 } 5233 } else { 5234 mCheckStates.put(lastPos, true); 5235 } 5236 } 5237 5238 if (checkedCountChanged && mChoiceActionMode != null) { 5239 mChoiceActionMode.invalidate(); 5240 } 5241 } 5242 5243 @Override 5244 protected void handleDataChanged() { 5245 int count = mItemCount; 5246 int lastHandledItemCount = mLastHandledItemCount; 5247 mLastHandledItemCount = mItemCount; 5248 5249 if (mChoiceMode != CHOICE_MODE_NONE && mAdapter != null && mAdapter.hasStableIds()) { 5250 confirmCheckedPositionsById(); 5251 } 5252 5253 // TODO: In the future we can recycle these views based on stable ID instead. 5254 mRecycler.clearTransientStateViews(); 5255 5256 if (count > 0) { 5257 int newPos; 5258 int selectablePos; 5259 5260 // Find the row we are supposed to sync to 5261 if (mNeedSync) { 5262 // Update this first, since setNextSelectedPositionInt inspects it 5263 mNeedSync = false; 5264 mPendingSync = null; 5265 5266 if (mTranscriptMode == TRANSCRIPT_MODE_ALWAYS_SCROLL) { 5267 mLayoutMode = LAYOUT_FORCE_BOTTOM; 5268 return; 5269 } else if (mTranscriptMode == TRANSCRIPT_MODE_NORMAL) { 5270 if (mForceTranscriptScroll) { 5271 mForceTranscriptScroll = false; 5272 mLayoutMode = LAYOUT_FORCE_BOTTOM; 5273 return; 5274 } 5275 final int childCount = getChildCount(); 5276 final int listBottom = getHeight() - getPaddingBottom(); 5277 final View lastChild = getChildAt(childCount - 1); 5278 final int lastBottom = lastChild != null ? lastChild.getBottom() : listBottom; 5279 if (mFirstPosition + childCount >= lastHandledItemCount && 5280 lastBottom <= listBottom) { 5281 mLayoutMode = LAYOUT_FORCE_BOTTOM; 5282 return; 5283 } 5284 // Something new came in and we didn't scroll; give the user a clue that 5285 // there's something new. 5286 awakenScrollBars(); 5287 } 5288 5289 switch (mSyncMode) { 5290 case SYNC_SELECTED_POSITION: 5291 if (isInTouchMode()) { 5292 // We saved our state when not in touch mode. (We know this because 5293 // mSyncMode is SYNC_SELECTED_POSITION.) Now we are trying to 5294 // restore in touch mode. Just leave mSyncPosition as it is (possibly 5295 // adjusting if the available range changed) and return. 5296 mLayoutMode = LAYOUT_SYNC; 5297 mSyncPosition = Math.min(Math.max(0, mSyncPosition), count - 1); 5298 5299 return; 5300 } else { 5301 // See if we can find a position in the new data with the same 5302 // id as the old selection. This will change mSyncPosition. 5303 newPos = findSyncPosition(); 5304 if (newPos >= 0) { 5305 // Found it. Now verify that new selection is still selectable 5306 selectablePos = lookForSelectablePosition(newPos, true); 5307 if (selectablePos == newPos) { 5308 // Same row id is selected 5309 mSyncPosition = newPos; 5310 5311 if (mSyncHeight == getHeight()) { 5312 // If we are at the same height as when we saved state, try 5313 // to restore the scroll position too. 5314 mLayoutMode = LAYOUT_SYNC; 5315 } else { 5316 // We are not the same height as when the selection was saved, so 5317 // don't try to restore the exact position 5318 mLayoutMode = LAYOUT_SET_SELECTION; 5319 } 5320 5321 // Restore selection 5322 setNextSelectedPositionInt(newPos); 5323 return; 5324 } 5325 } 5326 } 5327 break; 5328 case SYNC_FIRST_POSITION: 5329 // Leave mSyncPosition as it is -- just pin to available range 5330 mLayoutMode = LAYOUT_SYNC; 5331 mSyncPosition = Math.min(Math.max(0, mSyncPosition), count - 1); 5332 5333 return; 5334 } 5335 } 5336 5337 if (!isInTouchMode()) { 5338 // We couldn't find matching data -- try to use the same position 5339 newPos = getSelectedItemPosition(); 5340 5341 // Pin position to the available range 5342 if (newPos >= count) { 5343 newPos = count - 1; 5344 } 5345 if (newPos < 0) { 5346 newPos = 0; 5347 } 5348 5349 // Make sure we select something selectable -- first look down 5350 selectablePos = lookForSelectablePosition(newPos, true); 5351 5352 if (selectablePos >= 0) { 5353 setNextSelectedPositionInt(selectablePos); 5354 return; 5355 } else { 5356 // Looking down didn't work -- try looking up 5357 selectablePos = lookForSelectablePosition(newPos, false); 5358 if (selectablePos >= 0) { 5359 setNextSelectedPositionInt(selectablePos); 5360 return; 5361 } 5362 } 5363 } else { 5364 5365 // We already know where we want to resurrect the selection 5366 if (mResurrectToPosition >= 0) { 5367 return; 5368 } 5369 } 5370 5371 } 5372 5373 // Nothing is selected. Give up and reset everything. 5374 mLayoutMode = mStackFromBottom ? LAYOUT_FORCE_BOTTOM : LAYOUT_FORCE_TOP; 5375 mSelectedPosition = INVALID_POSITION; 5376 mSelectedRowId = INVALID_ROW_ID; 5377 mNextSelectedPosition = INVALID_POSITION; 5378 mNextSelectedRowId = INVALID_ROW_ID; 5379 mNeedSync = false; 5380 mPendingSync = null; 5381 mSelectorPosition = INVALID_POSITION; 5382 checkSelectionChanged(); 5383 } 5384 5385 @Override 5386 protected void onDisplayHint(int hint) { 5387 super.onDisplayHint(hint); 5388 switch (hint) { 5389 case INVISIBLE: 5390 if (mPopup != null && mPopup.isShowing()) { 5391 dismissPopup(); 5392 } 5393 break; 5394 case VISIBLE: 5395 if (mFiltered && mPopup != null && !mPopup.isShowing()) { 5396 showPopup(); 5397 } 5398 break; 5399 } 5400 mPopupHidden = hint == INVISIBLE; 5401 } 5402 5403 /** 5404 * Removes the filter window 5405 */ 5406 private void dismissPopup() { 5407 if (mPopup != null) { 5408 mPopup.dismiss(); 5409 } 5410 } 5411 5412 /** 5413 * Shows the filter window 5414 */ 5415 private void showPopup() { 5416 // Make sure we have a window before showing the popup 5417 if (getWindowVisibility() == View.VISIBLE) { 5418 createTextFilter(true); 5419 positionPopup(); 5420 // Make sure we get focus if we are showing the popup 5421 checkFocus(); 5422 } 5423 } 5424 5425 private void positionPopup() { 5426 int screenHeight = getResources().getDisplayMetrics().heightPixels; 5427 final int[] xy = new int[2]; 5428 getLocationOnScreen(xy); 5429 // TODO: The 20 below should come from the theme 5430 // TODO: And the gravity should be defined in the theme as well 5431 final int bottomGap = screenHeight - xy[1] - getHeight() + (int) (mDensityScale * 20); 5432 if (!mPopup.isShowing()) { 5433 mPopup.showAtLocation(this, Gravity.BOTTOM | Gravity.CENTER_HORIZONTAL, 5434 xy[0], bottomGap); 5435 } else { 5436 mPopup.update(xy[0], bottomGap, -1, -1); 5437 } 5438 } 5439 5440 /** 5441 * What is the distance between the source and destination rectangles given the direction of 5442 * focus navigation between them? The direction basically helps figure out more quickly what is 5443 * self evident by the relationship between the rects... 5444 * 5445 * @param source the source rectangle 5446 * @param dest the destination rectangle 5447 * @param direction the direction 5448 * @return the distance between the rectangles 5449 */ 5450 static int getDistance(Rect source, Rect dest, int direction) { 5451 int sX, sY; // source x, y 5452 int dX, dY; // dest x, y 5453 switch (direction) { 5454 case View.FOCUS_RIGHT: 5455 sX = source.right; 5456 sY = source.top + source.height() / 2; 5457 dX = dest.left; 5458 dY = dest.top + dest.height() / 2; 5459 break; 5460 case View.FOCUS_DOWN: 5461 sX = source.left + source.width() / 2; 5462 sY = source.bottom; 5463 dX = dest.left + dest.width() / 2; 5464 dY = dest.top; 5465 break; 5466 case View.FOCUS_LEFT: 5467 sX = source.left; 5468 sY = source.top + source.height() / 2; 5469 dX = dest.right; 5470 dY = dest.top + dest.height() / 2; 5471 break; 5472 case View.FOCUS_UP: 5473 sX = source.left + source.width() / 2; 5474 sY = source.top; 5475 dX = dest.left + dest.width() / 2; 5476 dY = dest.bottom; 5477 break; 5478 case View.FOCUS_FORWARD: 5479 case View.FOCUS_BACKWARD: 5480 sX = source.right + source.width() / 2; 5481 sY = source.top + source.height() / 2; 5482 dX = dest.left + dest.width() / 2; 5483 dY = dest.top + dest.height() / 2; 5484 break; 5485 default: 5486 throw new IllegalArgumentException("direction must be one of " 5487 + "{FOCUS_UP, FOCUS_DOWN, FOCUS_LEFT, FOCUS_RIGHT, " 5488 + "FOCUS_FORWARD, FOCUS_BACKWARD}."); 5489 } 5490 int deltaX = dX - sX; 5491 int deltaY = dY - sY; 5492 return deltaY * deltaY + deltaX * deltaX; 5493 } 5494 5495 @Override 5496 protected boolean isInFilterMode() { 5497 return mFiltered; 5498 } 5499 5500 /** 5501 * Sends a key to the text filter window 5502 * 5503 * @param keyCode The keycode for the event 5504 * @param event The actual key event 5505 * 5506 * @return True if the text filter handled the event, false otherwise. 5507 */ 5508 boolean sendToTextFilter(int keyCode, int count, KeyEvent event) { 5509 if (!acceptFilter()) { 5510 return false; 5511 } 5512 5513 boolean handled = false; 5514 boolean okToSend = true; 5515 switch (keyCode) { 5516 case KeyEvent.KEYCODE_DPAD_UP: 5517 case KeyEvent.KEYCODE_DPAD_DOWN: 5518 case KeyEvent.KEYCODE_DPAD_LEFT: 5519 case KeyEvent.KEYCODE_DPAD_RIGHT: 5520 case KeyEvent.KEYCODE_DPAD_CENTER: 5521 case KeyEvent.KEYCODE_ENTER: 5522 okToSend = false; 5523 break; 5524 case KeyEvent.KEYCODE_BACK: 5525 if (mFiltered && mPopup != null && mPopup.isShowing()) { 5526 if (event.getAction() == KeyEvent.ACTION_DOWN 5527 && event.getRepeatCount() == 0) { 5528 KeyEvent.DispatcherState state = getKeyDispatcherState(); 5529 if (state != null) { 5530 state.startTracking(event, this); 5531 } 5532 handled = true; 5533 } else if (event.getAction() == KeyEvent.ACTION_UP 5534 && event.isTracking() && !event.isCanceled()) { 5535 handled = true; 5536 mTextFilter.setText(""); 5537 } 5538 } 5539 okToSend = false; 5540 break; 5541 case KeyEvent.KEYCODE_SPACE: 5542 // Only send spaces once we are filtered 5543 okToSend = mFiltered; 5544 break; 5545 } 5546 5547 if (okToSend) { 5548 createTextFilter(true); 5549 5550 KeyEvent forwardEvent = event; 5551 if (forwardEvent.getRepeatCount() > 0) { 5552 forwardEvent = KeyEvent.changeTimeRepeat(event, event.getEventTime(), 0); 5553 } 5554 5555 int action = event.getAction(); 5556 switch (action) { 5557 case KeyEvent.ACTION_DOWN: 5558 handled = mTextFilter.onKeyDown(keyCode, forwardEvent); 5559 break; 5560 5561 case KeyEvent.ACTION_UP: 5562 handled = mTextFilter.onKeyUp(keyCode, forwardEvent); 5563 break; 5564 5565 case KeyEvent.ACTION_MULTIPLE: 5566 handled = mTextFilter.onKeyMultiple(keyCode, count, event); 5567 break; 5568 } 5569 } 5570 return handled; 5571 } 5572 5573 /** 5574 * Return an InputConnection for editing of the filter text. 5575 */ 5576 @Override 5577 public InputConnection onCreateInputConnection(EditorInfo outAttrs) { 5578 if (isTextFilterEnabled()) { 5579 if (mPublicInputConnection == null) { 5580 mDefInputConnection = new BaseInputConnection(this, false); 5581 mPublicInputConnection = new InputConnectionWrapper(outAttrs); 5582 } 5583 outAttrs.inputType = EditorInfo.TYPE_CLASS_TEXT | EditorInfo.TYPE_TEXT_VARIATION_FILTER; 5584 outAttrs.imeOptions = EditorInfo.IME_ACTION_DONE; 5585 return mPublicInputConnection; 5586 } 5587 return null; 5588 } 5589 5590 private class InputConnectionWrapper implements InputConnection { 5591 private final EditorInfo mOutAttrs; 5592 private InputConnection mTarget; 5593 5594 public InputConnectionWrapper(EditorInfo outAttrs) { 5595 mOutAttrs = outAttrs; 5596 } 5597 5598 private InputConnection getTarget() { 5599 if (mTarget == null) { 5600 mTarget = getTextFilterInput().onCreateInputConnection(mOutAttrs); 5601 } 5602 return mTarget; 5603 } 5604 5605 @Override 5606 public boolean reportFullscreenMode(boolean enabled) { 5607 // Use our own input connection, since it is 5608 // the "real" one the IME is talking with. 5609 return mDefInputConnection.reportFullscreenMode(enabled); 5610 } 5611 5612 @Override 5613 public boolean performEditorAction(int editorAction) { 5614 // The editor is off in its own window; we need to be 5615 // the one that does this. 5616 if (editorAction == EditorInfo.IME_ACTION_DONE) { 5617 InputMethodManager imm = (InputMethodManager) 5618 getContext().getSystemService(Context.INPUT_METHOD_SERVICE); 5619 if (imm != null) { 5620 imm.hideSoftInputFromWindow(getWindowToken(), 0); 5621 } 5622 return true; 5623 } 5624 return false; 5625 } 5626 5627 @Override 5628 public boolean sendKeyEvent(KeyEvent event) { 5629 // Use our own input connection, since the filter 5630 // text view may not be shown in a window so has 5631 // no ViewAncestor to dispatch events with. 5632 return mDefInputConnection.sendKeyEvent(event); 5633 } 5634 5635 @Override 5636 public CharSequence getTextBeforeCursor(int n, int flags) { 5637 if (mTarget == null) return ""; 5638 return mTarget.getTextBeforeCursor(n, flags); 5639 } 5640 5641 @Override 5642 public CharSequence getTextAfterCursor(int n, int flags) { 5643 if (mTarget == null) return ""; 5644 return mTarget.getTextAfterCursor(n, flags); 5645 } 5646 5647 @Override 5648 public CharSequence getSelectedText(int flags) { 5649 if (mTarget == null) return ""; 5650 return mTarget.getSelectedText(flags); 5651 } 5652 5653 @Override 5654 public int getCursorCapsMode(int reqModes) { 5655 if (mTarget == null) return InputType.TYPE_TEXT_FLAG_CAP_SENTENCES; 5656 return mTarget.getCursorCapsMode(reqModes); 5657 } 5658 5659 @Override 5660 public ExtractedText getExtractedText(ExtractedTextRequest request, int flags) { 5661 return getTarget().getExtractedText(request, flags); 5662 } 5663 5664 @Override 5665 public boolean deleteSurroundingText(int beforeLength, int afterLength) { 5666 return getTarget().deleteSurroundingText(beforeLength, afterLength); 5667 } 5668 5669 @Override 5670 public boolean setComposingText(CharSequence text, int newCursorPosition) { 5671 return getTarget().setComposingText(text, newCursorPosition); 5672 } 5673 5674 @Override 5675 public boolean setComposingRegion(int start, int end) { 5676 return getTarget().setComposingRegion(start, end); 5677 } 5678 5679 @Override 5680 public boolean finishComposingText() { 5681 return mTarget == null || mTarget.finishComposingText(); 5682 } 5683 5684 @Override 5685 public boolean commitText(CharSequence text, int newCursorPosition) { 5686 return getTarget().commitText(text, newCursorPosition); 5687 } 5688 5689 @Override 5690 public boolean commitCompletion(CompletionInfo text) { 5691 return getTarget().commitCompletion(text); 5692 } 5693 5694 @Override 5695 public boolean commitCorrection(CorrectionInfo correctionInfo) { 5696 return getTarget().commitCorrection(correctionInfo); 5697 } 5698 5699 @Override 5700 public boolean setSelection(int start, int end) { 5701 return getTarget().setSelection(start, end); 5702 } 5703 5704 @Override 5705 public boolean performContextMenuAction(int id) { 5706 return getTarget().performContextMenuAction(id); 5707 } 5708 5709 @Override 5710 public boolean beginBatchEdit() { 5711 return getTarget().beginBatchEdit(); 5712 } 5713 5714 @Override 5715 public boolean endBatchEdit() { 5716 return getTarget().endBatchEdit(); 5717 } 5718 5719 @Override 5720 public boolean clearMetaKeyStates(int states) { 5721 return getTarget().clearMetaKeyStates(states); 5722 } 5723 5724 @Override 5725 public boolean performPrivateCommand(String action, Bundle data) { 5726 return getTarget().performPrivateCommand(action, data); 5727 } 5728 5729 @Override 5730 public boolean requestCursorUpdates(int cursorUpdateMode) { 5731 return getTarget().requestCursorUpdates(cursorUpdateMode); 5732 } 5733 } 5734 5735 /** 5736 * For filtering we proxy an input connection to an internal text editor, 5737 * and this allows the proxying to happen. 5738 */ 5739 @Override 5740 public boolean checkInputConnectionProxy(View view) { 5741 return view == mTextFilter; 5742 } 5743 5744 /** 5745 * Creates the window for the text filter and populates it with an EditText field; 5746 * 5747 * @param animateEntrance true if the window should appear with an animation 5748 */ 5749 private void createTextFilter(boolean animateEntrance) { 5750 if (mPopup == null) { 5751 PopupWindow p = new PopupWindow(getContext()); 5752 p.setFocusable(false); 5753 p.setTouchable(false); 5754 p.setInputMethodMode(PopupWindow.INPUT_METHOD_NOT_NEEDED); 5755 p.setContentView(getTextFilterInput()); 5756 p.setWidth(LayoutParams.WRAP_CONTENT); 5757 p.setHeight(LayoutParams.WRAP_CONTENT); 5758 p.setBackgroundDrawable(null); 5759 mPopup = p; 5760 getViewTreeObserver().addOnGlobalLayoutListener(this); 5761 mGlobalLayoutListenerAddedFilter = true; 5762 } 5763 if (animateEntrance) { 5764 mPopup.setAnimationStyle(com.android.internal.R.style.Animation_TypingFilter); 5765 } else { 5766 mPopup.setAnimationStyle(com.android.internal.R.style.Animation_TypingFilterRestore); 5767 } 5768 } 5769 5770 private EditText getTextFilterInput() { 5771 if (mTextFilter == null) { 5772 final LayoutInflater layoutInflater = LayoutInflater.from(getContext()); 5773 mTextFilter = (EditText) layoutInflater.inflate( 5774 com.android.internal.R.layout.typing_filter, null); 5775 // For some reason setting this as the "real" input type changes 5776 // the text view in some way that it doesn't work, and I don't 5777 // want to figure out why this is. 5778 mTextFilter.setRawInputType(EditorInfo.TYPE_CLASS_TEXT 5779 | EditorInfo.TYPE_TEXT_VARIATION_FILTER); 5780 mTextFilter.setImeOptions(EditorInfo.IME_FLAG_NO_EXTRACT_UI); 5781 mTextFilter.addTextChangedListener(this); 5782 } 5783 return mTextFilter; 5784 } 5785 5786 /** 5787 * Clear the text filter. 5788 */ 5789 public void clearTextFilter() { 5790 if (mFiltered) { 5791 getTextFilterInput().setText(""); 5792 mFiltered = false; 5793 if (mPopup != null && mPopup.isShowing()) { 5794 dismissPopup(); 5795 } 5796 } 5797 } 5798 5799 /** 5800 * Returns if the ListView currently has a text filter. 5801 */ 5802 public boolean hasTextFilter() { 5803 return mFiltered; 5804 } 5805 5806 @Override 5807 public void onGlobalLayout() { 5808 if (isShown()) { 5809 // Show the popup if we are filtered 5810 if (mFiltered && mPopup != null && !mPopup.isShowing() && !mPopupHidden) { 5811 showPopup(); 5812 } 5813 } else { 5814 // Hide the popup when we are no longer visible 5815 if (mPopup != null && mPopup.isShowing()) { 5816 dismissPopup(); 5817 } 5818 } 5819 5820 } 5821 5822 /** 5823 * For our text watcher that is associated with the text filter. Does 5824 * nothing. 5825 */ 5826 @Override 5827 public void beforeTextChanged(CharSequence s, int start, int count, int after) { 5828 } 5829 5830 /** 5831 * For our text watcher that is associated with the text filter. Performs 5832 * the actual filtering as the text changes, and takes care of hiding and 5833 * showing the popup displaying the currently entered filter text. 5834 */ 5835 @Override 5836 public void onTextChanged(CharSequence s, int start, int before, int count) { 5837 if (isTextFilterEnabled()) { 5838 createTextFilter(true); 5839 int length = s.length(); 5840 boolean showing = mPopup.isShowing(); 5841 if (!showing && length > 0) { 5842 // Show the filter popup if necessary 5843 showPopup(); 5844 mFiltered = true; 5845 } else if (showing && length == 0) { 5846 // Remove the filter popup if the user has cleared all text 5847 dismissPopup(); 5848 mFiltered = false; 5849 } 5850 if (mAdapter instanceof Filterable) { 5851 Filter f = ((Filterable) mAdapter).getFilter(); 5852 // Filter should not be null when we reach this part 5853 if (f != null) { 5854 f.filter(s, this); 5855 } else { 5856 throw new IllegalStateException("You cannot call onTextChanged with a non " 5857 + "filterable adapter"); 5858 } 5859 } 5860 } 5861 } 5862 5863 /** 5864 * For our text watcher that is associated with the text filter. Does 5865 * nothing. 5866 */ 5867 @Override 5868 public void afterTextChanged(Editable s) { 5869 } 5870 5871 @Override 5872 public void onFilterComplete(int count) { 5873 if (mSelectedPosition < 0 && count > 0) { 5874 mResurrectToPosition = INVALID_POSITION; 5875 resurrectSelection(); 5876 } 5877 } 5878 5879 @Override 5880 protected ViewGroup.LayoutParams generateDefaultLayoutParams() { 5881 return new AbsListView.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, 5882 ViewGroup.LayoutParams.WRAP_CONTENT, 0); 5883 } 5884 5885 @Override 5886 protected ViewGroup.LayoutParams generateLayoutParams(ViewGroup.LayoutParams p) { 5887 return new LayoutParams(p); 5888 } 5889 5890 @Override 5891 public LayoutParams generateLayoutParams(AttributeSet attrs) { 5892 return new AbsListView.LayoutParams(getContext(), attrs); 5893 } 5894 5895 @Override 5896 protected boolean checkLayoutParams(ViewGroup.LayoutParams p) { 5897 return p instanceof AbsListView.LayoutParams; 5898 } 5899 5900 /** 5901 * Puts the list or grid into transcript mode. In this mode the list or grid will always scroll 5902 * to the bottom to show new items. 5903 * 5904 * @param mode the transcript mode to set 5905 * 5906 * @see #TRANSCRIPT_MODE_DISABLED 5907 * @see #TRANSCRIPT_MODE_NORMAL 5908 * @see #TRANSCRIPT_MODE_ALWAYS_SCROLL 5909 */ 5910 public void setTranscriptMode(int mode) { 5911 mTranscriptMode = mode; 5912 } 5913 5914 /** 5915 * Returns the current transcript mode. 5916 * 5917 * @return {@link #TRANSCRIPT_MODE_DISABLED}, {@link #TRANSCRIPT_MODE_NORMAL} or 5918 * {@link #TRANSCRIPT_MODE_ALWAYS_SCROLL} 5919 */ 5920 public int getTranscriptMode() { 5921 return mTranscriptMode; 5922 } 5923 5924 @Override 5925 public int getSolidColor() { 5926 return mCacheColorHint; 5927 } 5928 5929 /** 5930 * When set to a non-zero value, the cache color hint indicates that this list is always drawn 5931 * on top of a solid, single-color, opaque background. 5932 * 5933 * Zero means that what's behind this object is translucent (non solid) or is not made of a 5934 * single color. This hint will not affect any existing background drawable set on this view ( 5935 * typically set via {@link #setBackgroundDrawable(Drawable)}). 5936 * 5937 * @param color The background color 5938 */ 5939 public void setCacheColorHint(int color) { 5940 if (color != mCacheColorHint) { 5941 mCacheColorHint = color; 5942 int count = getChildCount(); 5943 for (int i = 0; i < count; i++) { 5944 getChildAt(i).setDrawingCacheBackgroundColor(color); 5945 } 5946 mRecycler.setCacheColorHint(color); 5947 } 5948 } 5949 5950 /** 5951 * When set to a non-zero value, the cache color hint indicates that this list is always drawn 5952 * on top of a solid, single-color, opaque background 5953 * 5954 * @return The cache color hint 5955 */ 5956 @ViewDebug.ExportedProperty(category = "drawing") 5957 public int getCacheColorHint() { 5958 return mCacheColorHint; 5959 } 5960 5961 /** 5962 * Move all views (excluding headers and footers) held by this AbsListView into the supplied 5963 * List. This includes views displayed on the screen as well as views stored in AbsListView's 5964 * internal view recycler. 5965 * 5966 * @param views A list into which to put the reclaimed views 5967 */ 5968 public void reclaimViews(List<View> views) { 5969 int childCount = getChildCount(); 5970 RecyclerListener listener = mRecycler.mRecyclerListener; 5971 5972 // Reclaim views on screen 5973 for (int i = 0; i < childCount; i++) { 5974 View child = getChildAt(i); 5975 AbsListView.LayoutParams lp = (AbsListView.LayoutParams) child.getLayoutParams(); 5976 // Don't reclaim header or footer views, or views that should be ignored 5977 if (lp != null && mRecycler.shouldRecycleViewType(lp.viewType)) { 5978 views.add(child); 5979 child.setAccessibilityDelegate(null); 5980 if (listener != null) { 5981 // Pretend they went through the scrap heap 5982 listener.onMovedToScrapHeap(child); 5983 } 5984 } 5985 } 5986 mRecycler.reclaimScrapViews(views); 5987 removeAllViewsInLayout(); 5988 } 5989 5990 private void finishGlows() { 5991 if (mEdgeGlowTop != null) { 5992 mEdgeGlowTop.finish(); 5993 mEdgeGlowBottom.finish(); 5994 } 5995 } 5996 5997 /** 5998 * Sets up this AbsListView to use a remote views adapter which connects to a RemoteViewsService 5999 * through the specified intent. 6000 * @param intent the intent used to identify the RemoteViewsService for the adapter to connect to. 6001 */ 6002 public void setRemoteViewsAdapter(Intent intent) { 6003 // Ensure that we don't already have a RemoteViewsAdapter that is bound to an existing 6004 // service handling the specified intent. 6005 if (mRemoteAdapter != null) { 6006 Intent.FilterComparison fcNew = new Intent.FilterComparison(intent); 6007 Intent.FilterComparison fcOld = new Intent.FilterComparison( 6008 mRemoteAdapter.getRemoteViewsServiceIntent()); 6009 if (fcNew.equals(fcOld)) { 6010 return; 6011 } 6012 } 6013 mDeferNotifyDataSetChanged = false; 6014 // Otherwise, create a new RemoteViewsAdapter for binding 6015 mRemoteAdapter = new RemoteViewsAdapter(getContext(), intent, this); 6016 if (mRemoteAdapter.isDataReady()) { 6017 setAdapter(mRemoteAdapter); 6018 } 6019 } 6020 6021 /** 6022 * Sets up the onClickHandler to be used by the RemoteViewsAdapter when inflating RemoteViews 6023 * 6024 * @param handler The OnClickHandler to use when inflating RemoteViews. 6025 * 6026 * @hide 6027 */ 6028 public void setRemoteViewsOnClickHandler(OnClickHandler handler) { 6029 // Ensure that we don't already have a RemoteViewsAdapter that is bound to an existing 6030 // service handling the specified intent. 6031 if (mRemoteAdapter != null) { 6032 mRemoteAdapter.setRemoteViewsOnClickHandler(handler); 6033 } 6034 } 6035 6036 /** 6037 * This defers a notifyDataSetChanged on the pending RemoteViewsAdapter if it has not 6038 * connected yet. 6039 */ 6040 @Override 6041 public void deferNotifyDataSetChanged() { 6042 mDeferNotifyDataSetChanged = true; 6043 } 6044 6045 /** 6046 * Called back when the adapter connects to the RemoteViewsService. 6047 */ 6048 @Override 6049 public boolean onRemoteAdapterConnected() { 6050 if (mRemoteAdapter != mAdapter) { 6051 setAdapter(mRemoteAdapter); 6052 if (mDeferNotifyDataSetChanged) { 6053 mRemoteAdapter.notifyDataSetChanged(); 6054 mDeferNotifyDataSetChanged = false; 6055 } 6056 return false; 6057 } else if (mRemoteAdapter != null) { 6058 mRemoteAdapter.superNotifyDataSetChanged(); 6059 return true; 6060 } 6061 return false; 6062 } 6063 6064 /** 6065 * Called back when the adapter disconnects from the RemoteViewsService. 6066 */ 6067 @Override 6068 public void onRemoteAdapterDisconnected() { 6069 // If the remote adapter disconnects, we keep it around 6070 // since the currently displayed items are still cached. 6071 // Further, we want the service to eventually reconnect 6072 // when necessary, as triggered by this view requesting 6073 // items from the Adapter. 6074 } 6075 6076 /** 6077 * Hints the RemoteViewsAdapter, if it exists, about which views are currently 6078 * being displayed by the AbsListView. 6079 */ 6080 void setVisibleRangeHint(int start, int end) { 6081 if (mRemoteAdapter != null) { 6082 mRemoteAdapter.setVisibleRangeHint(start, end); 6083 } 6084 } 6085 6086 /** 6087 * Sets the recycler listener to be notified whenever a View is set aside in 6088 * the recycler for later reuse. This listener can be used to free resources 6089 * associated to the View. 6090 * 6091 * @param listener The recycler listener to be notified of views set aside 6092 * in the recycler. 6093 * 6094 * @see android.widget.AbsListView.RecycleBin 6095 * @see android.widget.AbsListView.RecyclerListener 6096 */ 6097 public void setRecyclerListener(RecyclerListener listener) { 6098 mRecycler.mRecyclerListener = listener; 6099 } 6100 6101 class AdapterDataSetObserver extends AdapterView<ListAdapter>.AdapterDataSetObserver { 6102 @Override 6103 public void onChanged() { 6104 super.onChanged(); 6105 if (mFastScroll != null) { 6106 mFastScroll.onSectionsChanged(); 6107 } 6108 } 6109 6110 @Override 6111 public void onInvalidated() { 6112 super.onInvalidated(); 6113 if (mFastScroll != null) { 6114 mFastScroll.onSectionsChanged(); 6115 } 6116 } 6117 } 6118 6119 /** 6120 * A MultiChoiceModeListener receives events for {@link AbsListView#CHOICE_MODE_MULTIPLE_MODAL}. 6121 * It acts as the {@link ActionMode.Callback} for the selection mode and also receives 6122 * {@link #onItemCheckedStateChanged(ActionMode, int, long, boolean)} events when the user 6123 * selects and deselects list items. 6124 */ 6125 public interface MultiChoiceModeListener extends ActionMode.Callback { 6126 /** 6127 * Called when an item is checked or unchecked during selection mode. 6128 * 6129 * @param mode The {@link ActionMode} providing the selection mode 6130 * @param position Adapter position of the item that was checked or unchecked 6131 * @param id Adapter ID of the item that was checked or unchecked 6132 * @param checked <code>true</code> if the item is now checked, <code>false</code> 6133 * if the item is now unchecked. 6134 */ 6135 public void onItemCheckedStateChanged(ActionMode mode, 6136 int position, long id, boolean checked); 6137 } 6138 6139 class MultiChoiceModeWrapper implements MultiChoiceModeListener { 6140 private MultiChoiceModeListener mWrapped; 6141 6142 public void setWrapped(MultiChoiceModeListener wrapped) { 6143 mWrapped = wrapped; 6144 } 6145 6146 public boolean hasWrappedCallback() { 6147 return mWrapped != null; 6148 } 6149 6150 @Override 6151 public boolean onCreateActionMode(ActionMode mode, Menu menu) { 6152 if (mWrapped.onCreateActionMode(mode, menu)) { 6153 // Initialize checked graphic state? 6154 setLongClickable(false); 6155 return true; 6156 } 6157 return false; 6158 } 6159 6160 @Override 6161 public boolean onPrepareActionMode(ActionMode mode, Menu menu) { 6162 return mWrapped.onPrepareActionMode(mode, menu); 6163 } 6164 6165 @Override 6166 public boolean onActionItemClicked(ActionMode mode, MenuItem item) { 6167 return mWrapped.onActionItemClicked(mode, item); 6168 } 6169 6170 @Override 6171 public void onDestroyActionMode(ActionMode mode) { 6172 mWrapped.onDestroyActionMode(mode); 6173 mChoiceActionMode = null; 6174 6175 // Ending selection mode means deselecting everything. 6176 clearChoices(); 6177 6178 mDataChanged = true; 6179 rememberSyncState(); 6180 requestLayout(); 6181 6182 setLongClickable(true); 6183 } 6184 6185 @Override 6186 public void onItemCheckedStateChanged(ActionMode mode, 6187 int position, long id, boolean checked) { 6188 mWrapped.onItemCheckedStateChanged(mode, position, id, checked); 6189 6190 // If there are no items selected we no longer need the selection mode. 6191 if (getCheckedItemCount() == 0) { 6192 mode.finish(); 6193 } 6194 } 6195 } 6196 6197 /** 6198 * AbsListView extends LayoutParams to provide a place to hold the view type. 6199 */ 6200 public static class LayoutParams extends ViewGroup.LayoutParams { 6201 /** 6202 * View type for this view, as returned by 6203 * {@link android.widget.Adapter#getItemViewType(int) } 6204 */ 6205 @ViewDebug.ExportedProperty(category = "list", mapping = { 6206 @ViewDebug.IntToString(from = ITEM_VIEW_TYPE_IGNORE, to = "ITEM_VIEW_TYPE_IGNORE"), 6207 @ViewDebug.IntToString(from = ITEM_VIEW_TYPE_HEADER_OR_FOOTER, to = "ITEM_VIEW_TYPE_HEADER_OR_FOOTER") 6208 }) 6209 int viewType; 6210 6211 /** 6212 * When this boolean is set, the view has been added to the AbsListView 6213 * at least once. It is used to know whether headers/footers have already 6214 * been added to the list view and whether they should be treated as 6215 * recycled views or not. 6216 */ 6217 @ViewDebug.ExportedProperty(category = "list") 6218 boolean recycledHeaderFooter; 6219 6220 /** 6221 * When an AbsListView is measured with an AT_MOST measure spec, it needs 6222 * to obtain children views to measure itself. When doing so, the children 6223 * are not attached to the window, but put in the recycler which assumes 6224 * they've been attached before. Setting this flag will force the reused 6225 * view to be attached to the window rather than just attached to the 6226 * parent. 6227 */ 6228 @ViewDebug.ExportedProperty(category = "list") 6229 boolean forceAdd; 6230 6231 /** 6232 * The position the view was removed from when pulled out of the 6233 * scrap heap. 6234 * @hide 6235 */ 6236 int scrappedFromPosition; 6237 6238 /** 6239 * The ID the view represents 6240 */ 6241 long itemId = -1; 6242 6243 public LayoutParams(Context c, AttributeSet attrs) { 6244 super(c, attrs); 6245 } 6246 6247 public LayoutParams(int w, int h) { 6248 super(w, h); 6249 } 6250 6251 public LayoutParams(int w, int h, int viewType) { 6252 super(w, h); 6253 this.viewType = viewType; 6254 } 6255 6256 public LayoutParams(ViewGroup.LayoutParams source) { 6257 super(source); 6258 } 6259 } 6260 6261 /** 6262 * A RecyclerListener is used to receive a notification whenever a View is placed 6263 * inside the RecycleBin's scrap heap. This listener is used to free resources 6264 * associated to Views placed in the RecycleBin. 6265 * 6266 * @see android.widget.AbsListView.RecycleBin 6267 * @see android.widget.AbsListView#setRecyclerListener(android.widget.AbsListView.RecyclerListener) 6268 */ 6269 public static interface RecyclerListener { 6270 /** 6271 * Indicates that the specified View was moved into the recycler's scrap heap. 6272 * The view is not displayed on screen any more and any expensive resource 6273 * associated with the view should be discarded. 6274 * 6275 * @param view 6276 */ 6277 void onMovedToScrapHeap(View view); 6278 } 6279 6280 /** 6281 * The RecycleBin facilitates reuse of views across layouts. The RecycleBin has two levels of 6282 * storage: ActiveViews and ScrapViews. ActiveViews are those views which were onscreen at the 6283 * start of a layout. By construction, they are displaying current information. At the end of 6284 * layout, all views in ActiveViews are demoted to ScrapViews. ScrapViews are old views that 6285 * could potentially be used by the adapter to avoid allocating views unnecessarily. 6286 * 6287 * @see android.widget.AbsListView#setRecyclerListener(android.widget.AbsListView.RecyclerListener) 6288 * @see android.widget.AbsListView.RecyclerListener 6289 */ 6290 class RecycleBin { 6291 private RecyclerListener mRecyclerListener; 6292 6293 /** 6294 * The position of the first view stored in mActiveViews. 6295 */ 6296 private int mFirstActivePosition; 6297 6298 /** 6299 * Views that were on screen at the start of layout. This array is populated at the start of 6300 * layout, and at the end of layout all view in mActiveViews are moved to mScrapViews. 6301 * Views in mActiveViews represent a contiguous range of Views, with position of the first 6302 * view store in mFirstActivePosition. 6303 */ 6304 private View[] mActiveViews = new View[0]; 6305 6306 /** 6307 * Unsorted views that can be used by the adapter as a convert view. 6308 */ 6309 private ArrayList<View>[] mScrapViews; 6310 6311 private int mViewTypeCount; 6312 6313 private ArrayList<View> mCurrentScrap; 6314 6315 private ArrayList<View> mSkippedScrap; 6316 6317 private SparseArray<View> mTransientStateViews; 6318 private LongSparseArray<View> mTransientStateViewsById; 6319 6320 public void setViewTypeCount(int viewTypeCount) { 6321 if (viewTypeCount < 1) { 6322 throw new IllegalArgumentException("Can't have a viewTypeCount < 1"); 6323 } 6324 //noinspection unchecked 6325 ArrayList<View>[] scrapViews = new ArrayList[viewTypeCount]; 6326 for (int i = 0; i < viewTypeCount; i++) { 6327 scrapViews[i] = new ArrayList<View>(); 6328 } 6329 mViewTypeCount = viewTypeCount; 6330 mCurrentScrap = scrapViews[0]; 6331 mScrapViews = scrapViews; 6332 } 6333 6334 public void markChildrenDirty() { 6335 if (mViewTypeCount == 1) { 6336 final ArrayList<View> scrap = mCurrentScrap; 6337 final int scrapCount = scrap.size(); 6338 for (int i = 0; i < scrapCount; i++) { 6339 scrap.get(i).forceLayout(); 6340 } 6341 } else { 6342 final int typeCount = mViewTypeCount; 6343 for (int i = 0; i < typeCount; i++) { 6344 final ArrayList<View> scrap = mScrapViews[i]; 6345 final int scrapCount = scrap.size(); 6346 for (int j = 0; j < scrapCount; j++) { 6347 scrap.get(j).forceLayout(); 6348 } 6349 } 6350 } 6351 if (mTransientStateViews != null) { 6352 final int count = mTransientStateViews.size(); 6353 for (int i = 0; i < count; i++) { 6354 mTransientStateViews.valueAt(i).forceLayout(); 6355 } 6356 } 6357 if (mTransientStateViewsById != null) { 6358 final int count = mTransientStateViewsById.size(); 6359 for (int i = 0; i < count; i++) { 6360 mTransientStateViewsById.valueAt(i).forceLayout(); 6361 } 6362 } 6363 } 6364 6365 public boolean shouldRecycleViewType(int viewType) { 6366 return viewType >= 0; 6367 } 6368 6369 /** 6370 * Clears the scrap heap. 6371 */ 6372 void clear() { 6373 if (mViewTypeCount == 1) { 6374 final ArrayList<View> scrap = mCurrentScrap; 6375 clearScrap(scrap); 6376 } else { 6377 final int typeCount = mViewTypeCount; 6378 for (int i = 0; i < typeCount; i++) { 6379 final ArrayList<View> scrap = mScrapViews[i]; 6380 clearScrap(scrap); 6381 } 6382 } 6383 6384 clearTransientStateViews(); 6385 } 6386 6387 /** 6388 * Fill ActiveViews with all of the children of the AbsListView. 6389 * 6390 * @param childCount The minimum number of views mActiveViews should hold 6391 * @param firstActivePosition The position of the first view that will be stored in 6392 * mActiveViews 6393 */ 6394 void fillActiveViews(int childCount, int firstActivePosition) { 6395 if (mActiveViews.length < childCount) { 6396 mActiveViews = new View[childCount]; 6397 } 6398 mFirstActivePosition = firstActivePosition; 6399 6400 //noinspection MismatchedReadAndWriteOfArray 6401 final View[] activeViews = mActiveViews; 6402 for (int i = 0; i < childCount; i++) { 6403 View child = getChildAt(i); 6404 AbsListView.LayoutParams lp = (AbsListView.LayoutParams) child.getLayoutParams(); 6405 // Don't put header or footer views into the scrap heap 6406 if (lp != null && lp.viewType != ITEM_VIEW_TYPE_HEADER_OR_FOOTER) { 6407 // Note: We do place AdapterView.ITEM_VIEW_TYPE_IGNORE in active views. 6408 // However, we will NOT place them into scrap views. 6409 activeViews[i] = child; 6410 } 6411 } 6412 } 6413 6414 /** 6415 * Get the view corresponding to the specified position. The view will be removed from 6416 * mActiveViews if it is found. 6417 * 6418 * @param position The position to look up in mActiveViews 6419 * @return The view if it is found, null otherwise 6420 */ 6421 View getActiveView(int position) { 6422 int index = position - mFirstActivePosition; 6423 final View[] activeViews = mActiveViews; 6424 if (index >=0 && index < activeViews.length) { 6425 final View match = activeViews[index]; 6426 activeViews[index] = null; 6427 return match; 6428 } 6429 return null; 6430 } 6431 6432 View getTransientStateView(int position) { 6433 if (mAdapter != null && mAdapterHasStableIds && mTransientStateViewsById != null) { 6434 long id = mAdapter.getItemId(position); 6435 View result = mTransientStateViewsById.get(id); 6436 mTransientStateViewsById.remove(id); 6437 return result; 6438 } 6439 if (mTransientStateViews != null) { 6440 final int index = mTransientStateViews.indexOfKey(position); 6441 if (index >= 0) { 6442 View result = mTransientStateViews.valueAt(index); 6443 mTransientStateViews.removeAt(index); 6444 return result; 6445 } 6446 } 6447 return null; 6448 } 6449 6450 /** 6451 * Dumps and fully detaches any currently saved views with transient 6452 * state. 6453 */ 6454 void clearTransientStateViews() { 6455 final SparseArray<View> viewsByPos = mTransientStateViews; 6456 if (viewsByPos != null) { 6457 final int N = viewsByPos.size(); 6458 for (int i = 0; i < N; i++) { 6459 removeDetachedView(viewsByPos.valueAt(i), false); 6460 } 6461 viewsByPos.clear(); 6462 } 6463 6464 final LongSparseArray<View> viewsById = mTransientStateViewsById; 6465 if (viewsById != null) { 6466 final int N = viewsById.size(); 6467 for (int i = 0; i < N; i++) { 6468 removeDetachedView(viewsById.valueAt(i), false); 6469 } 6470 viewsById.clear(); 6471 } 6472 } 6473 6474 /** 6475 * @return A view from the ScrapViews collection. These are unordered. 6476 */ 6477 View getScrapView(int position) { 6478 if (mViewTypeCount == 1) { 6479 return retrieveFromScrap(mCurrentScrap, position); 6480 } else { 6481 final int whichScrap = mAdapter.getItemViewType(position); 6482 if (whichScrap >= 0 && whichScrap < mScrapViews.length) { 6483 return retrieveFromScrap(mScrapViews[whichScrap], position); 6484 } 6485 } 6486 return null; 6487 } 6488 6489 /** 6490 * Puts a view into the list of scrap views. 6491 * <p> 6492 * If the list data hasn't changed or the adapter has stable IDs, views 6493 * with transient state will be preserved for later retrieval. 6494 * 6495 * @param scrap The view to add 6496 * @param position The view's position within its parent 6497 */ 6498 void addScrapView(View scrap, int position) { 6499 final AbsListView.LayoutParams lp = (AbsListView.LayoutParams) scrap.getLayoutParams(); 6500 if (lp == null) { 6501 return; 6502 } 6503 6504 lp.scrappedFromPosition = position; 6505 6506 // Remove but don't scrap header or footer views, or views that 6507 // should otherwise not be recycled. 6508 final int viewType = lp.viewType; 6509 if (!shouldRecycleViewType(viewType)) { 6510 return; 6511 } 6512 6513 scrap.dispatchStartTemporaryDetach(); 6514 6515 // The the accessibility state of the view may change while temporary 6516 // detached and we do not allow detached views to fire accessibility 6517 // events. So we are announcing that the subtree changed giving a chance 6518 // to clients holding on to a view in this subtree to refresh it. 6519 notifyViewAccessibilityStateChangedIfNeeded( 6520 AccessibilityEvent.CONTENT_CHANGE_TYPE_SUBTREE); 6521 6522 // Don't scrap views that have transient state. 6523 final boolean scrapHasTransientState = scrap.hasTransientState(); 6524 if (scrapHasTransientState) { 6525 if (mAdapter != null && mAdapterHasStableIds) { 6526 // If the adapter has stable IDs, we can reuse the view for 6527 // the same data. 6528 if (mTransientStateViewsById == null) { 6529 mTransientStateViewsById = new LongSparseArray<View>(); 6530 } 6531 mTransientStateViewsById.put(lp.itemId, scrap); 6532 } else if (!mDataChanged) { 6533 // If the data hasn't changed, we can reuse the views at 6534 // their old positions. 6535 if (mTransientStateViews == null) { 6536 mTransientStateViews = new SparseArray<View>(); 6537 } 6538 mTransientStateViews.put(position, scrap); 6539 } else { 6540 // Otherwise, we'll have to remove the view and start over. 6541 if (mSkippedScrap == null) { 6542 mSkippedScrap = new ArrayList<View>(); 6543 } 6544 mSkippedScrap.add(scrap); 6545 } 6546 } else { 6547 if (mViewTypeCount == 1) { 6548 mCurrentScrap.add(scrap); 6549 } else { 6550 mScrapViews[viewType].add(scrap); 6551 } 6552 6553 if (mRecyclerListener != null) { 6554 mRecyclerListener.onMovedToScrapHeap(scrap); 6555 } 6556 } 6557 } 6558 6559 /** 6560 * Finish the removal of any views that skipped the scrap heap. 6561 */ 6562 void removeSkippedScrap() { 6563 if (mSkippedScrap == null) { 6564 return; 6565 } 6566 final int count = mSkippedScrap.size(); 6567 for (int i = 0; i < count; i++) { 6568 removeDetachedView(mSkippedScrap.get(i), false); 6569 } 6570 mSkippedScrap.clear(); 6571 } 6572 6573 /** 6574 * Move all views remaining in mActiveViews to mScrapViews. 6575 */ 6576 void scrapActiveViews() { 6577 final View[] activeViews = mActiveViews; 6578 final boolean hasListener = mRecyclerListener != null; 6579 final boolean multipleScraps = mViewTypeCount > 1; 6580 6581 ArrayList<View> scrapViews = mCurrentScrap; 6582 final int count = activeViews.length; 6583 for (int i = count - 1; i >= 0; i--) { 6584 final View victim = activeViews[i]; 6585 if (victim != null) { 6586 final AbsListView.LayoutParams lp 6587 = (AbsListView.LayoutParams) victim.getLayoutParams(); 6588 final int whichScrap = lp.viewType; 6589 6590 activeViews[i] = null; 6591 6592 if (victim.hasTransientState()) { 6593 // Store views with transient state for later use. 6594 victim.dispatchStartTemporaryDetach(); 6595 6596 if (mAdapter != null && mAdapterHasStableIds) { 6597 if (mTransientStateViewsById == null) { 6598 mTransientStateViewsById = new LongSparseArray<View>(); 6599 } 6600 long id = mAdapter.getItemId(mFirstActivePosition + i); 6601 mTransientStateViewsById.put(id, victim); 6602 } else if (!mDataChanged) { 6603 if (mTransientStateViews == null) { 6604 mTransientStateViews = new SparseArray<View>(); 6605 } 6606 mTransientStateViews.put(mFirstActivePosition + i, victim); 6607 } else if (whichScrap != ITEM_VIEW_TYPE_HEADER_OR_FOOTER) { 6608 // The data has changed, we can't keep this view. 6609 removeDetachedView(victim, false); 6610 } 6611 } else if (!shouldRecycleViewType(whichScrap)) { 6612 // Discard non-recyclable views except headers/footers. 6613 if (whichScrap != ITEM_VIEW_TYPE_HEADER_OR_FOOTER) { 6614 removeDetachedView(victim, false); 6615 } 6616 } else { 6617 // Store everything else on the appropriate scrap heap. 6618 if (multipleScraps) { 6619 scrapViews = mScrapViews[whichScrap]; 6620 } 6621 6622 victim.dispatchStartTemporaryDetach(); 6623 lp.scrappedFromPosition = mFirstActivePosition + i; 6624 scrapViews.add(victim); 6625 6626 if (hasListener) { 6627 mRecyclerListener.onMovedToScrapHeap(victim); 6628 } 6629 } 6630 } 6631 } 6632 6633 pruneScrapViews(); 6634 } 6635 6636 /** 6637 * Makes sure that the size of mScrapViews does not exceed the size of 6638 * mActiveViews, which can happen if an adapter does not recycle its 6639 * views. Removes cached transient state views that no longer have 6640 * transient state. 6641 */ 6642 private void pruneScrapViews() { 6643 final int maxViews = mActiveViews.length; 6644 final int viewTypeCount = mViewTypeCount; 6645 final ArrayList<View>[] scrapViews = mScrapViews; 6646 for (int i = 0; i < viewTypeCount; ++i) { 6647 final ArrayList<View> scrapPile = scrapViews[i]; 6648 int size = scrapPile.size(); 6649 final int extras = size - maxViews; 6650 size--; 6651 for (int j = 0; j < extras; j++) { 6652 removeDetachedView(scrapPile.remove(size--), false); 6653 } 6654 } 6655 6656 final SparseArray<View> transViewsByPos = mTransientStateViews; 6657 if (transViewsByPos != null) { 6658 for (int i = 0; i < transViewsByPos.size(); i++) { 6659 final View v = transViewsByPos.valueAt(i); 6660 if (!v.hasTransientState()) { 6661 removeDetachedView(v, false); 6662 transViewsByPos.removeAt(i); 6663 i--; 6664 } 6665 } 6666 } 6667 6668 final LongSparseArray<View> transViewsById = mTransientStateViewsById; 6669 if (transViewsById != null) { 6670 for (int i = 0; i < transViewsById.size(); i++) { 6671 final View v = transViewsById.valueAt(i); 6672 if (!v.hasTransientState()) { 6673 removeDetachedView(v, false); 6674 transViewsById.removeAt(i); 6675 i--; 6676 } 6677 } 6678 } 6679 } 6680 6681 /** 6682 * Puts all views in the scrap heap into the supplied list. 6683 */ 6684 void reclaimScrapViews(List<View> views) { 6685 if (mViewTypeCount == 1) { 6686 views.addAll(mCurrentScrap); 6687 } else { 6688 final int viewTypeCount = mViewTypeCount; 6689 final ArrayList<View>[] scrapViews = mScrapViews; 6690 for (int i = 0; i < viewTypeCount; ++i) { 6691 final ArrayList<View> scrapPile = scrapViews[i]; 6692 views.addAll(scrapPile); 6693 } 6694 } 6695 } 6696 6697 /** 6698 * Updates the cache color hint of all known views. 6699 * 6700 * @param color The new cache color hint. 6701 */ 6702 void setCacheColorHint(int color) { 6703 if (mViewTypeCount == 1) { 6704 final ArrayList<View> scrap = mCurrentScrap; 6705 final int scrapCount = scrap.size(); 6706 for (int i = 0; i < scrapCount; i++) { 6707 scrap.get(i).setDrawingCacheBackgroundColor(color); 6708 } 6709 } else { 6710 final int typeCount = mViewTypeCount; 6711 for (int i = 0; i < typeCount; i++) { 6712 final ArrayList<View> scrap = mScrapViews[i]; 6713 final int scrapCount = scrap.size(); 6714 for (int j = 0; j < scrapCount; j++) { 6715 scrap.get(j).setDrawingCacheBackgroundColor(color); 6716 } 6717 } 6718 } 6719 // Just in case this is called during a layout pass 6720 final View[] activeViews = mActiveViews; 6721 final int count = activeViews.length; 6722 for (int i = 0; i < count; ++i) { 6723 final View victim = activeViews[i]; 6724 if (victim != null) { 6725 victim.setDrawingCacheBackgroundColor(color); 6726 } 6727 } 6728 } 6729 6730 private View retrieveFromScrap(ArrayList<View> scrapViews, int position) { 6731 final int size = scrapViews.size(); 6732 if (size > 0) { 6733 // See if we still have a view for this position or ID. 6734 for (int i = 0; i < size; i++) { 6735 final View view = scrapViews.get(i); 6736 final AbsListView.LayoutParams params = 6737 (AbsListView.LayoutParams) view.getLayoutParams(); 6738 6739 if (mAdapterHasStableIds) { 6740 final long id = mAdapter.getItemId(position); 6741 if (id == params.itemId) { 6742 return scrapViews.remove(i); 6743 } 6744 } else if (params.scrappedFromPosition == position) { 6745 final View scrap = scrapViews.remove(i); 6746 clearAccessibilityFromScrap(scrap); 6747 return scrap; 6748 } 6749 } 6750 final View scrap = scrapViews.remove(size - 1); 6751 clearAccessibilityFromScrap(scrap); 6752 return scrap; 6753 } else { 6754 return null; 6755 } 6756 } 6757 6758 private void clearScrap(final ArrayList<View> scrap) { 6759 final int scrapCount = scrap.size(); 6760 for (int j = 0; j < scrapCount; j++) { 6761 removeDetachedView(scrap.remove(scrapCount - 1 - j), false); 6762 } 6763 } 6764 6765 private void clearAccessibilityFromScrap(View view) { 6766 if (view.isAccessibilityFocused()) { 6767 view.clearAccessibilityFocus(); 6768 } 6769 view.setAccessibilityDelegate(null); 6770 } 6771 6772 private void removeDetachedView(View child, boolean animate) { 6773 child.setAccessibilityDelegate(null); 6774 AbsListView.this.removeDetachedView(child, animate); 6775 } 6776 } 6777 6778 /** 6779 * Returns the height of the view for the specified position. 6780 * 6781 * @param position the item position 6782 * @return view height in pixels 6783 */ 6784 int getHeightForPosition(int position) { 6785 final int firstVisiblePosition = getFirstVisiblePosition(); 6786 final int childCount = getChildCount(); 6787 final int index = position - firstVisiblePosition; 6788 if (index >= 0 && index < childCount) { 6789 // Position is on-screen, use existing view. 6790 final View view = getChildAt(index); 6791 return view.getHeight(); 6792 } else { 6793 // Position is off-screen, obtain & recycle view. 6794 final View view = obtainView(position, mIsScrap); 6795 view.measure(mWidthMeasureSpec, MeasureSpec.UNSPECIFIED); 6796 final int height = view.getMeasuredHeight(); 6797 mRecycler.addScrapView(view, position); 6798 return height; 6799 } 6800 } 6801 6802 /** 6803 * Sets the selected item and positions the selection y pixels from the top edge 6804 * of the ListView. (If in touch mode, the item will not be selected but it will 6805 * still be positioned appropriately.) 6806 * 6807 * @param position Index (starting at 0) of the data item to be selected. 6808 * @param y The distance from the top edge of the ListView (plus padding) that the 6809 * item will be positioned. 6810 */ 6811 public void setSelectionFromTop(int position, int y) { 6812 if (mAdapter == null) { 6813 return; 6814 } 6815 6816 if (!isInTouchMode()) { 6817 position = lookForSelectablePosition(position, true); 6818 if (position >= 0) { 6819 setNextSelectedPositionInt(position); 6820 } 6821 } else { 6822 mResurrectToPosition = position; 6823 } 6824 6825 if (position >= 0) { 6826 mLayoutMode = LAYOUT_SPECIFIC; 6827 mSpecificTop = mListPadding.top + y; 6828 6829 if (mNeedSync) { 6830 mSyncPosition = position; 6831 mSyncRowId = mAdapter.getItemId(position); 6832 } 6833 6834 if (mPositionScroller != null) { 6835 mPositionScroller.stop(); 6836 } 6837 requestLayout(); 6838 } 6839 } 6840 6841 /** 6842 * Abstract positon scroller used to handle smooth scrolling. 6843 */ 6844 static abstract class AbsPositionScroller { 6845 public abstract void start(int position); 6846 public abstract void start(int position, int boundPosition); 6847 public abstract void startWithOffset(int position, int offset); 6848 public abstract void startWithOffset(int position, int offset, int duration); 6849 public abstract void stop(); 6850 } 6851 6852 /** 6853 * Default position scroller that simulates a fling. 6854 */ 6855 class PositionScroller extends AbsPositionScroller implements Runnable { 6856 private static final int SCROLL_DURATION = 200; 6857 6858 private static final int MOVE_DOWN_POS = 1; 6859 private static final int MOVE_UP_POS = 2; 6860 private static final int MOVE_DOWN_BOUND = 3; 6861 private static final int MOVE_UP_BOUND = 4; 6862 private static final int MOVE_OFFSET = 5; 6863 6864 private int mMode; 6865 private int mTargetPos; 6866 private int mBoundPos; 6867 private int mLastSeenPos; 6868 private int mScrollDuration; 6869 private final int mExtraScroll; 6870 6871 private int mOffsetFromTop; 6872 6873 PositionScroller() { 6874 mExtraScroll = ViewConfiguration.get(mContext).getScaledFadingEdgeLength(); 6875 } 6876 6877 @Override 6878 public void start(final int position) { 6879 stop(); 6880 6881 if (mDataChanged) { 6882 // Wait until we're back in a stable state to try this. 6883 mPositionScrollAfterLayout = new Runnable() { 6884 @Override public void run() { 6885 start(position); 6886 } 6887 }; 6888 return; 6889 } 6890 6891 final int childCount = getChildCount(); 6892 if (childCount == 0) { 6893 // Can't scroll without children. 6894 return; 6895 } 6896 6897 final int firstPos = mFirstPosition; 6898 final int lastPos = firstPos + childCount - 1; 6899 6900 int viewTravelCount; 6901 int clampedPosition = Math.max(0, Math.min(getCount() - 1, position)); 6902 if (clampedPosition < firstPos) { 6903 viewTravelCount = firstPos - clampedPosition + 1; 6904 mMode = MOVE_UP_POS; 6905 } else if (clampedPosition > lastPos) { 6906 viewTravelCount = clampedPosition - lastPos + 1; 6907 mMode = MOVE_DOWN_POS; 6908 } else { 6909 scrollToVisible(clampedPosition, INVALID_POSITION, SCROLL_DURATION); 6910 return; 6911 } 6912 6913 if (viewTravelCount > 0) { 6914 mScrollDuration = SCROLL_DURATION / viewTravelCount; 6915 } else { 6916 mScrollDuration = SCROLL_DURATION; 6917 } 6918 mTargetPos = clampedPosition; 6919 mBoundPos = INVALID_POSITION; 6920 mLastSeenPos = INVALID_POSITION; 6921 6922 postOnAnimation(this); 6923 } 6924 6925 @Override 6926 public void start(final int position, final int boundPosition) { 6927 stop(); 6928 6929 if (boundPosition == INVALID_POSITION) { 6930 start(position); 6931 return; 6932 } 6933 6934 if (mDataChanged) { 6935 // Wait until we're back in a stable state to try this. 6936 mPositionScrollAfterLayout = new Runnable() { 6937 @Override public void run() { 6938 start(position, boundPosition); 6939 } 6940 }; 6941 return; 6942 } 6943 6944 final int childCount = getChildCount(); 6945 if (childCount == 0) { 6946 // Can't scroll without children. 6947 return; 6948 } 6949 6950 final int firstPos = mFirstPosition; 6951 final int lastPos = firstPos + childCount - 1; 6952 6953 int viewTravelCount; 6954 int clampedPosition = Math.max(0, Math.min(getCount() - 1, position)); 6955 if (clampedPosition < firstPos) { 6956 final int boundPosFromLast = lastPos - boundPosition; 6957 if (boundPosFromLast < 1) { 6958 // Moving would shift our bound position off the screen. Abort. 6959 return; 6960 } 6961 6962 final int posTravel = firstPos - clampedPosition + 1; 6963 final int boundTravel = boundPosFromLast - 1; 6964 if (boundTravel < posTravel) { 6965 viewTravelCount = boundTravel; 6966 mMode = MOVE_UP_BOUND; 6967 } else { 6968 viewTravelCount = posTravel; 6969 mMode = MOVE_UP_POS; 6970 } 6971 } else if (clampedPosition > lastPos) { 6972 final int boundPosFromFirst = boundPosition - firstPos; 6973 if (boundPosFromFirst < 1) { 6974 // Moving would shift our bound position off the screen. Abort. 6975 return; 6976 } 6977 6978 final int posTravel = clampedPosition - lastPos + 1; 6979 final int boundTravel = boundPosFromFirst - 1; 6980 if (boundTravel < posTravel) { 6981 viewTravelCount = boundTravel; 6982 mMode = MOVE_DOWN_BOUND; 6983 } else { 6984 viewTravelCount = posTravel; 6985 mMode = MOVE_DOWN_POS; 6986 } 6987 } else { 6988 scrollToVisible(clampedPosition, boundPosition, SCROLL_DURATION); 6989 return; 6990 } 6991 6992 if (viewTravelCount > 0) { 6993 mScrollDuration = SCROLL_DURATION / viewTravelCount; 6994 } else { 6995 mScrollDuration = SCROLL_DURATION; 6996 } 6997 mTargetPos = clampedPosition; 6998 mBoundPos = boundPosition; 6999 mLastSeenPos = INVALID_POSITION; 7000 7001 postOnAnimation(this); 7002 } 7003 7004 @Override 7005 public void startWithOffset(int position, int offset) { 7006 startWithOffset(position, offset, SCROLL_DURATION); 7007 } 7008 7009 @Override 7010 public void startWithOffset(final int position, int offset, final int duration) { 7011 stop(); 7012 7013 if (mDataChanged) { 7014 // Wait until we're back in a stable state to try this. 7015 final int postOffset = offset; 7016 mPositionScrollAfterLayout = new Runnable() { 7017 @Override public void run() { 7018 startWithOffset(position, postOffset, duration); 7019 } 7020 }; 7021 return; 7022 } 7023 7024 final int childCount = getChildCount(); 7025 if (childCount == 0) { 7026 // Can't scroll without children. 7027 return; 7028 } 7029 7030 offset += getPaddingTop(); 7031 7032 mTargetPos = Math.max(0, Math.min(getCount() - 1, position)); 7033 mOffsetFromTop = offset; 7034 mBoundPos = INVALID_POSITION; 7035 mLastSeenPos = INVALID_POSITION; 7036 mMode = MOVE_OFFSET; 7037 7038 final int firstPos = mFirstPosition; 7039 final int lastPos = firstPos + childCount - 1; 7040 7041 int viewTravelCount; 7042 if (mTargetPos < firstPos) { 7043 viewTravelCount = firstPos - mTargetPos; 7044 } else if (mTargetPos > lastPos) { 7045 viewTravelCount = mTargetPos - lastPos; 7046 } else { 7047 // On-screen, just scroll. 7048 final int targetTop = getChildAt(mTargetPos - firstPos).getTop(); 7049 smoothScrollBy(targetTop - offset, duration, true); 7050 return; 7051 } 7052 7053 // Estimate how many screens we should travel 7054 final float screenTravelCount = (float) viewTravelCount / childCount; 7055 mScrollDuration = screenTravelCount < 1 ? 7056 duration : (int) (duration / screenTravelCount); 7057 mLastSeenPos = INVALID_POSITION; 7058 7059 postOnAnimation(this); 7060 } 7061 7062 /** 7063 * Scroll such that targetPos is in the visible padded region without scrolling 7064 * boundPos out of view. Assumes targetPos is onscreen. 7065 */ 7066 private void scrollToVisible(int targetPos, int boundPos, int duration) { 7067 final int firstPos = mFirstPosition; 7068 final int childCount = getChildCount(); 7069 final int lastPos = firstPos + childCount - 1; 7070 final int paddedTop = mListPadding.top; 7071 final int paddedBottom = getHeight() - mListPadding.bottom; 7072 7073 if (targetPos < firstPos || targetPos > lastPos) { 7074 Log.w(TAG, "scrollToVisible called with targetPos " + targetPos + 7075 " not visible [" + firstPos + ", " + lastPos + "]"); 7076 } 7077 if (boundPos < firstPos || boundPos > lastPos) { 7078 // boundPos doesn't matter, it's already offscreen. 7079 boundPos = INVALID_POSITION; 7080 } 7081 7082 final View targetChild = getChildAt(targetPos - firstPos); 7083 final int targetTop = targetChild.getTop(); 7084 final int targetBottom = targetChild.getBottom(); 7085 int scrollBy = 0; 7086 7087 if (targetBottom > paddedBottom) { 7088 scrollBy = targetBottom - paddedBottom; 7089 } 7090 if (targetTop < paddedTop) { 7091 scrollBy = targetTop - paddedTop; 7092 } 7093 7094 if (scrollBy == 0) { 7095 return; 7096 } 7097 7098 if (boundPos >= 0) { 7099 final View boundChild = getChildAt(boundPos - firstPos); 7100 final int boundTop = boundChild.getTop(); 7101 final int boundBottom = boundChild.getBottom(); 7102 final int absScroll = Math.abs(scrollBy); 7103 7104 if (scrollBy < 0 && boundBottom + absScroll > paddedBottom) { 7105 // Don't scroll the bound view off the bottom of the screen. 7106 scrollBy = Math.max(0, boundBottom - paddedBottom); 7107 } else if (scrollBy > 0 && boundTop - absScroll < paddedTop) { 7108 // Don't scroll the bound view off the top of the screen. 7109 scrollBy = Math.min(0, boundTop - paddedTop); 7110 } 7111 } 7112 7113 smoothScrollBy(scrollBy, duration); 7114 } 7115 7116 @Override 7117 public void stop() { 7118 removeCallbacks(this); 7119 } 7120 7121 @Override 7122 public void run() { 7123 final int listHeight = getHeight(); 7124 final int firstPos = mFirstPosition; 7125 7126 switch (mMode) { 7127 case MOVE_DOWN_POS: { 7128 final int lastViewIndex = getChildCount() - 1; 7129 final int lastPos = firstPos + lastViewIndex; 7130 7131 if (lastViewIndex < 0) { 7132 return; 7133 } 7134 7135 if (lastPos == mLastSeenPos) { 7136 // No new views, let things keep going. 7137 postOnAnimation(this); 7138 return; 7139 } 7140 7141 final View lastView = getChildAt(lastViewIndex); 7142 final int lastViewHeight = lastView.getHeight(); 7143 final int lastViewTop = lastView.getTop(); 7144 final int lastViewPixelsShowing = listHeight - lastViewTop; 7145 final int extraScroll = lastPos < mItemCount - 1 ? 7146 Math.max(mListPadding.bottom, mExtraScroll) : mListPadding.bottom; 7147 7148 final int scrollBy = lastViewHeight - lastViewPixelsShowing + extraScroll; 7149 smoothScrollBy(scrollBy, mScrollDuration, true); 7150 7151 mLastSeenPos = lastPos; 7152 if (lastPos < mTargetPos) { 7153 postOnAnimation(this); 7154 } 7155 break; 7156 } 7157 7158 case MOVE_DOWN_BOUND: { 7159 final int nextViewIndex = 1; 7160 final int childCount = getChildCount(); 7161 7162 if (firstPos == mBoundPos || childCount <= nextViewIndex 7163 || firstPos + childCount >= mItemCount) { 7164 return; 7165 } 7166 final int nextPos = firstPos + nextViewIndex; 7167 7168 if (nextPos == mLastSeenPos) { 7169 // No new views, let things keep going. 7170 postOnAnimation(this); 7171 return; 7172 } 7173 7174 final View nextView = getChildAt(nextViewIndex); 7175 final int nextViewHeight = nextView.getHeight(); 7176 final int nextViewTop = nextView.getTop(); 7177 final int extraScroll = Math.max(mListPadding.bottom, mExtraScroll); 7178 if (nextPos < mBoundPos) { 7179 smoothScrollBy(Math.max(0, nextViewHeight + nextViewTop - extraScroll), 7180 mScrollDuration, true); 7181 7182 mLastSeenPos = nextPos; 7183 7184 postOnAnimation(this); 7185 } else { 7186 if (nextViewTop > extraScroll) { 7187 smoothScrollBy(nextViewTop - extraScroll, mScrollDuration, true); 7188 } 7189 } 7190 break; 7191 } 7192 7193 case MOVE_UP_POS: { 7194 if (firstPos == mLastSeenPos) { 7195 // No new views, let things keep going. 7196 postOnAnimation(this); 7197 return; 7198 } 7199 7200 final View firstView = getChildAt(0); 7201 if (firstView == null) { 7202 return; 7203 } 7204 final int firstViewTop = firstView.getTop(); 7205 final int extraScroll = firstPos > 0 ? 7206 Math.max(mExtraScroll, mListPadding.top) : mListPadding.top; 7207 7208 smoothScrollBy(firstViewTop - extraScroll, mScrollDuration, true); 7209 7210 mLastSeenPos = firstPos; 7211 7212 if (firstPos > mTargetPos) { 7213 postOnAnimation(this); 7214 } 7215 break; 7216 } 7217 7218 case MOVE_UP_BOUND: { 7219 final int lastViewIndex = getChildCount() - 2; 7220 if (lastViewIndex < 0) { 7221 return; 7222 } 7223 final int lastPos = firstPos + lastViewIndex; 7224 7225 if (lastPos == mLastSeenPos) { 7226 // No new views, let things keep going. 7227 postOnAnimation(this); 7228 return; 7229 } 7230 7231 final View lastView = getChildAt(lastViewIndex); 7232 final int lastViewHeight = lastView.getHeight(); 7233 final int lastViewTop = lastView.getTop(); 7234 final int lastViewPixelsShowing = listHeight - lastViewTop; 7235 final int extraScroll = Math.max(mListPadding.top, mExtraScroll); 7236 mLastSeenPos = lastPos; 7237 if (lastPos > mBoundPos) { 7238 smoothScrollBy(-(lastViewPixelsShowing - extraScroll), mScrollDuration, true); 7239 postOnAnimation(this); 7240 } else { 7241 final int bottom = listHeight - extraScroll; 7242 final int lastViewBottom = lastViewTop + lastViewHeight; 7243 if (bottom > lastViewBottom) { 7244 smoothScrollBy(-(bottom - lastViewBottom), mScrollDuration, true); 7245 } 7246 } 7247 break; 7248 } 7249 7250 case MOVE_OFFSET: { 7251 if (mLastSeenPos == firstPos) { 7252 // No new views, let things keep going. 7253 postOnAnimation(this); 7254 return; 7255 } 7256 7257 mLastSeenPos = firstPos; 7258 7259 final int childCount = getChildCount(); 7260 final int position = mTargetPos; 7261 final int lastPos = firstPos + childCount - 1; 7262 7263 int viewTravelCount = 0; 7264 if (position < firstPos) { 7265 viewTravelCount = firstPos - position + 1; 7266 } else if (position > lastPos) { 7267 viewTravelCount = position - lastPos; 7268 } 7269 7270 // Estimate how many screens we should travel 7271 final float screenTravelCount = (float) viewTravelCount / childCount; 7272 7273 final float modifier = Math.min(Math.abs(screenTravelCount), 1.f); 7274 if (position < firstPos) { 7275 final int distance = (int) (-getHeight() * modifier); 7276 final int duration = (int) (mScrollDuration * modifier); 7277 smoothScrollBy(distance, duration, true); 7278 postOnAnimation(this); 7279 } else if (position > lastPos) { 7280 final int distance = (int) (getHeight() * modifier); 7281 final int duration = (int) (mScrollDuration * modifier); 7282 smoothScrollBy(distance, duration, true); 7283 postOnAnimation(this); 7284 } else { 7285 // On-screen, just scroll. 7286 final int targetTop = getChildAt(position - firstPos).getTop(); 7287 final int distance = targetTop - mOffsetFromTop; 7288 final int duration = (int) (mScrollDuration * 7289 ((float) Math.abs(distance) / getHeight())); 7290 smoothScrollBy(distance, duration, true); 7291 } 7292 break; 7293 } 7294 7295 default: 7296 break; 7297 } 7298 } 7299 } 7300} 7301