AbsListView.java revision 9d849a2f6351caed83105b90cab79223ec2bfbd3
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 com.android.internal.R; 20 21import android.content.Context; 22import android.content.Intent; 23import android.content.res.TypedArray; 24import android.graphics.Canvas; 25import android.graphics.Rect; 26import android.graphics.drawable.Drawable; 27import android.graphics.drawable.TransitionDrawable; 28import android.os.Debug; 29import android.os.Handler; 30import android.os.Parcel; 31import android.os.Parcelable; 32import android.os.StrictMode; 33import android.text.Editable; 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.AccessibilityNodeInfo; 61import android.view.inputmethod.BaseInputConnection; 62import android.view.inputmethod.EditorInfo; 63import android.view.inputmethod.InputConnection; 64import android.view.inputmethod.InputConnectionWrapper; 65import android.view.inputmethod.InputMethodManager; 66 67import java.util.ArrayList; 68import java.util.List; 69 70/** 71 * Base class that can be used to implement virtualized lists of items. A list does 72 * not have a spatial definition here. For instance, subclases of this class can 73 * display the content of the list in a grid, in a carousel, as stack, etc. 74 * 75 * @attr ref android.R.styleable#AbsListView_listSelector 76 * @attr ref android.R.styleable#AbsListView_drawSelectorOnTop 77 * @attr ref android.R.styleable#AbsListView_stackFromBottom 78 * @attr ref android.R.styleable#AbsListView_scrollingCache 79 * @attr ref android.R.styleable#AbsListView_textFilterEnabled 80 * @attr ref android.R.styleable#AbsListView_transcriptMode 81 * @attr ref android.R.styleable#AbsListView_cacheColorHint 82 * @attr ref android.R.styleable#AbsListView_fastScrollEnabled 83 * @attr ref android.R.styleable#AbsListView_smoothScrollbar 84 * @attr ref android.R.styleable#AbsListView_choiceMode 85 */ 86public abstract class AbsListView extends AdapterView<ListAdapter> implements TextWatcher, 87 ViewTreeObserver.OnGlobalLayoutListener, Filter.FilterListener, 88 ViewTreeObserver.OnTouchModeChangeListener, 89 RemoteViewsAdapter.RemoteAdapterConnectionCallback { 90 91 @SuppressWarnings("UnusedDeclaration") 92 private static final String TAG = "AbsListView"; 93 94 /** 95 * Disables the transcript mode. 96 * 97 * @see #setTranscriptMode(int) 98 */ 99 public static final int TRANSCRIPT_MODE_DISABLED = 0; 100 /** 101 * The list will automatically scroll to the bottom when a data set change 102 * notification is received and only if the last item is already visible 103 * on screen. 104 * 105 * @see #setTranscriptMode(int) 106 */ 107 public static final int TRANSCRIPT_MODE_NORMAL = 1; 108 /** 109 * The list will automatically scroll to the bottom, no matter what items 110 * are currently visible. 111 * 112 * @see #setTranscriptMode(int) 113 */ 114 public static final int TRANSCRIPT_MODE_ALWAYS_SCROLL = 2; 115 116 /** 117 * Indicates that we are not in the middle of a touch gesture 118 */ 119 static final int TOUCH_MODE_REST = -1; 120 121 /** 122 * Indicates we just received the touch event and we are waiting to see if the it is a tap or a 123 * scroll gesture. 124 */ 125 static final int TOUCH_MODE_DOWN = 0; 126 127 /** 128 * Indicates the touch has been recognized as a tap and we are now waiting to see if the touch 129 * is a longpress 130 */ 131 static final int TOUCH_MODE_TAP = 1; 132 133 /** 134 * Indicates we have waited for everything we can wait for, but the user's finger is still down 135 */ 136 static final int TOUCH_MODE_DONE_WAITING = 2; 137 138 /** 139 * Indicates the touch gesture is a scroll 140 */ 141 static final int TOUCH_MODE_SCROLL = 3; 142 143 /** 144 * Indicates the view is in the process of being flung 145 */ 146 static final int TOUCH_MODE_FLING = 4; 147 148 /** 149 * Indicates the touch gesture is an overscroll - a scroll beyond the beginning or end. 150 */ 151 static final int TOUCH_MODE_OVERSCROLL = 5; 152 153 /** 154 * Indicates the view is being flung outside of normal content bounds 155 * and will spring back. 156 */ 157 static final int TOUCH_MODE_OVERFLING = 6; 158 159 /** 160 * Regular layout - usually an unsolicited layout from the view system 161 */ 162 static final int LAYOUT_NORMAL = 0; 163 164 /** 165 * Show the first item 166 */ 167 static final int LAYOUT_FORCE_TOP = 1; 168 169 /** 170 * Force the selected item to be on somewhere on the screen 171 */ 172 static final int LAYOUT_SET_SELECTION = 2; 173 174 /** 175 * Show the last item 176 */ 177 static final int LAYOUT_FORCE_BOTTOM = 3; 178 179 /** 180 * Make a mSelectedItem appear in a specific location and build the rest of 181 * the views from there. The top is specified by mSpecificTop. 182 */ 183 static final int LAYOUT_SPECIFIC = 4; 184 185 /** 186 * Layout to sync as a result of a data change. Restore mSyncPosition to have its top 187 * at mSpecificTop 188 */ 189 static final int LAYOUT_SYNC = 5; 190 191 /** 192 * Layout as a result of using the navigation keys 193 */ 194 static final int LAYOUT_MOVE_SELECTION = 6; 195 196 /** 197 * Normal list that does not indicate choices 198 */ 199 public static final int CHOICE_MODE_NONE = 0; 200 201 /** 202 * The list allows up to one choice 203 */ 204 public static final int CHOICE_MODE_SINGLE = 1; 205 206 /** 207 * The list allows multiple choices 208 */ 209 public static final int CHOICE_MODE_MULTIPLE = 2; 210 211 /** 212 * The list allows multiple choices in a modal selection mode 213 */ 214 public static final int CHOICE_MODE_MULTIPLE_MODAL = 3; 215 216 /** 217 * Controls if/how the user may choose/check items in the list 218 */ 219 int mChoiceMode = CHOICE_MODE_NONE; 220 221 /** 222 * Controls CHOICE_MODE_MULTIPLE_MODAL. null when inactive. 223 */ 224 ActionMode mChoiceActionMode; 225 226 /** 227 * Wrapper for the multiple choice mode callback; AbsListView needs to perform 228 * a few extra actions around what application code does. 229 */ 230 MultiChoiceModeWrapper mMultiChoiceModeCallback; 231 232 /** 233 * Running count of how many items are currently checked 234 */ 235 int mCheckedItemCount; 236 237 /** 238 * Running state of which positions are currently checked 239 */ 240 SparseBooleanArray mCheckStates; 241 242 /** 243 * Running state of which IDs are currently checked. 244 * If there is a value for a given key, the checked state for that ID is true 245 * and the value holds the last known position in the adapter for that id. 246 */ 247 LongSparseArray<Integer> mCheckedIdStates; 248 249 /** 250 * Controls how the next layout will happen 251 */ 252 int mLayoutMode = LAYOUT_NORMAL; 253 254 /** 255 * Should be used by subclasses to listen to changes in the dataset 256 */ 257 AdapterDataSetObserver mDataSetObserver; 258 259 /** 260 * The adapter containing the data to be displayed by this view 261 */ 262 ListAdapter mAdapter; 263 264 /** 265 * The remote adapter containing the data to be displayed by this view to be set 266 */ 267 private RemoteViewsAdapter mRemoteAdapter; 268 269 /** 270 * If mAdapter != null, whenever this is true the adapter has stable IDs. 271 */ 272 boolean mAdapterHasStableIds; 273 274 /** 275 * This flag indicates the a full notify is required when the RemoteViewsAdapter connects 276 */ 277 private boolean mDeferNotifyDataSetChanged = false; 278 279 /** 280 * Indicates whether the list selector should be drawn on top of the children or behind 281 */ 282 boolean mDrawSelectorOnTop = false; 283 284 /** 285 * The drawable used to draw the selector 286 */ 287 Drawable mSelector; 288 289 /** 290 * The current position of the selector in the list. 291 */ 292 int mSelectorPosition = INVALID_POSITION; 293 294 /** 295 * Defines the selector's location and dimension at drawing time 296 */ 297 Rect mSelectorRect = new Rect(); 298 299 /** 300 * The data set used to store unused views that should be reused during the next layout 301 * to avoid creating new ones 302 */ 303 final RecycleBin mRecycler = new RecycleBin(); 304 305 /** 306 * The selection's left padding 307 */ 308 int mSelectionLeftPadding = 0; 309 310 /** 311 * The selection's top padding 312 */ 313 int mSelectionTopPadding = 0; 314 315 /** 316 * The selection's right padding 317 */ 318 int mSelectionRightPadding = 0; 319 320 /** 321 * The selection's bottom padding 322 */ 323 int mSelectionBottomPadding = 0; 324 325 /** 326 * This view's padding 327 */ 328 Rect mListPadding = new Rect(); 329 330 /** 331 * Subclasses must retain their measure spec from onMeasure() into this member 332 */ 333 int mWidthMeasureSpec = 0; 334 335 /** 336 * The top scroll indicator 337 */ 338 View mScrollUp; 339 340 /** 341 * The down scroll indicator 342 */ 343 View mScrollDown; 344 345 /** 346 * When the view is scrolling, this flag is set to true to indicate subclasses that 347 * the drawing cache was enabled on the children 348 */ 349 boolean mCachingStarted; 350 boolean mCachingActive; 351 352 /** 353 * The position of the view that received the down motion event 354 */ 355 int mMotionPosition; 356 357 /** 358 * The offset to the top of the mMotionPosition view when the down motion event was received 359 */ 360 int mMotionViewOriginalTop; 361 362 /** 363 * The desired offset to the top of the mMotionPosition view after a scroll 364 */ 365 int mMotionViewNewTop; 366 367 /** 368 * The X value associated with the the down motion event 369 */ 370 int mMotionX; 371 372 /** 373 * The Y value associated with the the down motion event 374 */ 375 int mMotionY; 376 377 /** 378 * One of TOUCH_MODE_REST, TOUCH_MODE_DOWN, TOUCH_MODE_TAP, TOUCH_MODE_SCROLL, or 379 * TOUCH_MODE_DONE_WAITING 380 */ 381 int mTouchMode = TOUCH_MODE_REST; 382 383 /** 384 * Y value from on the previous motion event (if any) 385 */ 386 int mLastY; 387 388 /** 389 * How far the finger moved before we started scrolling 390 */ 391 int mMotionCorrection; 392 393 /** 394 * Determines speed during touch scrolling 395 */ 396 private VelocityTracker mVelocityTracker; 397 398 /** 399 * Handles one frame of a fling 400 */ 401 private FlingRunnable mFlingRunnable; 402 403 /** 404 * Handles scrolling between positions within the list. 405 */ 406 private PositionScroller mPositionScroller; 407 408 /** 409 * The offset in pixels form the top of the AdapterView to the top 410 * of the currently selected view. Used to save and restore state. 411 */ 412 int mSelectedTop = 0; 413 414 /** 415 * Indicates whether the list is stacked from the bottom edge or 416 * the top edge. 417 */ 418 boolean mStackFromBottom; 419 420 /** 421 * When set to true, the list automatically discards the children's 422 * bitmap cache after scrolling. 423 */ 424 boolean mScrollingCacheEnabled; 425 426 /** 427 * Whether or not to enable the fast scroll feature on this list 428 */ 429 boolean mFastScrollEnabled; 430 431 /** 432 * Optional callback to notify client when scroll position has changed 433 */ 434 private OnScrollListener mOnScrollListener; 435 436 /** 437 * Keeps track of our accessory window 438 */ 439 PopupWindow mPopup; 440 441 /** 442 * Used with type filter window 443 */ 444 EditText mTextFilter; 445 446 /** 447 * Indicates whether to use pixels-based or position-based scrollbar 448 * properties. 449 */ 450 private boolean mSmoothScrollbarEnabled = true; 451 452 /** 453 * Indicates that this view supports filtering 454 */ 455 private boolean mTextFilterEnabled; 456 457 /** 458 * Indicates that this view is currently displaying a filtered view of the data 459 */ 460 private boolean mFiltered; 461 462 /** 463 * Rectangle used for hit testing children 464 */ 465 private Rect mTouchFrame; 466 467 /** 468 * The position to resurrect the selected position to. 469 */ 470 int mResurrectToPosition = INVALID_POSITION; 471 472 private ContextMenuInfo mContextMenuInfo = null; 473 474 /** 475 * Maximum distance to record overscroll 476 */ 477 int mOverscrollMax; 478 479 /** 480 * Content height divided by this is the overscroll limit. 481 */ 482 static final int OVERSCROLL_LIMIT_DIVISOR = 3; 483 484 /** 485 * How many positions in either direction we will search to try to 486 * find a checked item with a stable ID that moved position across 487 * a data set change. If the item isn't found it will be unselected. 488 */ 489 private static final int CHECK_POSITION_SEARCH_DISTANCE = 20; 490 491 /** 492 * Used to request a layout when we changed touch mode 493 */ 494 private static final int TOUCH_MODE_UNKNOWN = -1; 495 private static final int TOUCH_MODE_ON = 0; 496 private static final int TOUCH_MODE_OFF = 1; 497 498 private int mLastTouchMode = TOUCH_MODE_UNKNOWN; 499 500 private static final boolean PROFILE_SCROLLING = false; 501 private boolean mScrollProfilingStarted = false; 502 503 private static final boolean PROFILE_FLINGING = false; 504 private boolean mFlingProfilingStarted = false; 505 506 /** 507 * The StrictMode "critical time span" objects to catch animation 508 * stutters. Non-null when a time-sensitive animation is 509 * in-flight. Must call finish() on them when done animating. 510 * These are no-ops on user builds. 511 */ 512 private StrictMode.Span mScrollStrictSpan = null; 513 private StrictMode.Span mFlingStrictSpan = null; 514 515 /** 516 * The last CheckForLongPress runnable we posted, if any 517 */ 518 private CheckForLongPress mPendingCheckForLongPress; 519 520 /** 521 * The last CheckForTap runnable we posted, if any 522 */ 523 private Runnable mPendingCheckForTap; 524 525 /** 526 * The last CheckForKeyLongPress runnable we posted, if any 527 */ 528 private CheckForKeyLongPress mPendingCheckForKeyLongPress; 529 530 /** 531 * Acts upon click 532 */ 533 private AbsListView.PerformClick mPerformClick; 534 535 /** 536 * Delayed action for touch mode. 537 */ 538 private Runnable mTouchModeReset; 539 540 /** 541 * This view is in transcript mode -- it shows the bottom of the list when the data 542 * changes 543 */ 544 private int mTranscriptMode; 545 546 /** 547 * Indicates that this list is always drawn on top of a solid, single-color, opaque 548 * background 549 */ 550 private int mCacheColorHint; 551 552 /** 553 * The select child's view (from the adapter's getView) is enabled. 554 */ 555 private boolean mIsChildViewEnabled; 556 557 /** 558 * The last scroll state reported to clients through {@link OnScrollListener}. 559 */ 560 private int mLastScrollState = OnScrollListener.SCROLL_STATE_IDLE; 561 562 /** 563 * Helper object that renders and controls the fast scroll thumb. 564 */ 565 private FastScroller mFastScroller; 566 567 private boolean mGlobalLayoutListenerAddedFilter; 568 569 private int mTouchSlop; 570 private float mDensityScale; 571 572 private InputConnection mDefInputConnection; 573 private InputConnectionWrapper mPublicInputConnection; 574 575 private Runnable mClearScrollingCache; 576 private int mMinimumVelocity; 577 private int mMaximumVelocity; 578 private float mVelocityScale = 1.0f; 579 580 final boolean[] mIsScrap = new boolean[1]; 581 582 // True when the popup should be hidden because of a call to 583 // dispatchDisplayHint() 584 private boolean mPopupHidden; 585 586 /** 587 * ID of the active pointer. This is used to retain consistency during 588 * drags/flings if multiple pointers are used. 589 */ 590 private int mActivePointerId = INVALID_POINTER; 591 592 /** 593 * Sentinel value for no current active pointer. 594 * Used by {@link #mActivePointerId}. 595 */ 596 private static final int INVALID_POINTER = -1; 597 598 /** 599 * Maximum distance to overscroll by during edge effects 600 */ 601 int mOverscrollDistance; 602 603 /** 604 * Maximum distance to overfling during edge effects 605 */ 606 int mOverflingDistance; 607 608 // These two EdgeGlows are always set and used together. 609 // Checking one for null is as good as checking both. 610 611 /** 612 * Tracks the state of the top edge glow. 613 */ 614 private EdgeEffect mEdgeGlowTop; 615 616 /** 617 * Tracks the state of the bottom edge glow. 618 */ 619 private EdgeEffect mEdgeGlowBottom; 620 621 /** 622 * An estimate of how many pixels are between the top of the list and 623 * the top of the first position in the adapter, based on the last time 624 * we saw it. Used to hint where to draw edge glows. 625 */ 626 private int mFirstPositionDistanceGuess; 627 628 /** 629 * An estimate of how many pixels are between the bottom of the list and 630 * the bottom of the last position in the adapter, based on the last time 631 * we saw it. Used to hint where to draw edge glows. 632 */ 633 private int mLastPositionDistanceGuess; 634 635 /** 636 * Used for determining when to cancel out of overscroll. 637 */ 638 private int mDirection = 0; 639 640 /** 641 * Tracked on measurement in transcript mode. Makes sure that we can still pin to 642 * the bottom correctly on resizes. 643 */ 644 private boolean mForceTranscriptScroll; 645 646 private int mGlowPaddingLeft; 647 private int mGlowPaddingRight; 648 649 private int mLastAccessibilityScrollEventFromIndex; 650 private int mLastAccessibilityScrollEventToIndex; 651 652 /** 653 * Track if we are currently attached to a window. 654 */ 655 boolean mIsAttached; 656 657 /** 658 * Track the item count from the last time we handled a data change. 659 */ 660 private int mLastHandledItemCount; 661 662 /** 663 * Interface definition for a callback to be invoked when the list or grid 664 * has been scrolled. 665 */ 666 public interface OnScrollListener { 667 668 /** 669 * The view is not scrolling. Note navigating the list using the trackball counts as 670 * being in the idle state since these transitions are not animated. 671 */ 672 public static int SCROLL_STATE_IDLE = 0; 673 674 /** 675 * The user is scrolling using touch, and their finger is still on the screen 676 */ 677 public static int SCROLL_STATE_TOUCH_SCROLL = 1; 678 679 /** 680 * The user had previously been scrolling using touch and had performed a fling. The 681 * animation is now coasting to a stop 682 */ 683 public static int SCROLL_STATE_FLING = 2; 684 685 /** 686 * Callback method to be invoked while the list view or grid view is being scrolled. If the 687 * view is being scrolled, this method will be called before the next frame of the scroll is 688 * rendered. In particular, it will be called before any calls to 689 * {@link Adapter#getView(int, View, ViewGroup)}. 690 * 691 * @param view The view whose scroll state is being reported 692 * 693 * @param scrollState The current scroll state. One of {@link #SCROLL_STATE_IDLE}, 694 * {@link #SCROLL_STATE_TOUCH_SCROLL} or {@link #SCROLL_STATE_IDLE}. 695 */ 696 public void onScrollStateChanged(AbsListView view, int scrollState); 697 698 /** 699 * Callback method to be invoked when the list or grid has been scrolled. This will be 700 * called after the scroll has completed 701 * @param view The view whose scroll state is being reported 702 * @param firstVisibleItem the index of the first visible cell (ignore if 703 * visibleItemCount == 0) 704 * @param visibleItemCount the number of visible cells 705 * @param totalItemCount the number of items in the list adaptor 706 */ 707 public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, 708 int totalItemCount); 709 } 710 711 /** 712 * The top-level view of a list item can implement this interface to allow 713 * itself to modify the bounds of the selection shown for that item. 714 */ 715 public interface SelectionBoundsAdjuster { 716 /** 717 * Called to allow the list item to adjust the bounds shown for 718 * its selection. 719 * 720 * @param bounds On call, this contains the bounds the list has 721 * selected for the item (that is the bounds of the entire view). The 722 * values can be modified as desired. 723 */ 724 public void adjustListItemSelectionBounds(Rect bounds); 725 } 726 727 public AbsListView(Context context) { 728 super(context); 729 initAbsListView(); 730 731 setVerticalScrollBarEnabled(true); 732 TypedArray a = context.obtainStyledAttributes(R.styleable.View); 733 initializeScrollbars(a); 734 a.recycle(); 735 } 736 737 public AbsListView(Context context, AttributeSet attrs) { 738 this(context, attrs, com.android.internal.R.attr.absListViewStyle); 739 } 740 741 public AbsListView(Context context, AttributeSet attrs, int defStyle) { 742 super(context, attrs, defStyle); 743 initAbsListView(); 744 745 TypedArray a = context.obtainStyledAttributes(attrs, 746 com.android.internal.R.styleable.AbsListView, defStyle, 0); 747 748 Drawable d = a.getDrawable(com.android.internal.R.styleable.AbsListView_listSelector); 749 if (d != null) { 750 setSelector(d); 751 } 752 753 mDrawSelectorOnTop = a.getBoolean( 754 com.android.internal.R.styleable.AbsListView_drawSelectorOnTop, false); 755 756 boolean stackFromBottom = a.getBoolean(R.styleable.AbsListView_stackFromBottom, false); 757 setStackFromBottom(stackFromBottom); 758 759 boolean scrollingCacheEnabled = a.getBoolean(R.styleable.AbsListView_scrollingCache, true); 760 setScrollingCacheEnabled(scrollingCacheEnabled); 761 762 boolean useTextFilter = a.getBoolean(R.styleable.AbsListView_textFilterEnabled, false); 763 setTextFilterEnabled(useTextFilter); 764 765 int transcriptMode = a.getInt(R.styleable.AbsListView_transcriptMode, 766 TRANSCRIPT_MODE_DISABLED); 767 setTranscriptMode(transcriptMode); 768 769 int color = a.getColor(R.styleable.AbsListView_cacheColorHint, 0); 770 setCacheColorHint(color); 771 772 boolean enableFastScroll = a.getBoolean(R.styleable.AbsListView_fastScrollEnabled, false); 773 setFastScrollEnabled(enableFastScroll); 774 775 boolean smoothScrollbar = a.getBoolean(R.styleable.AbsListView_smoothScrollbar, true); 776 setSmoothScrollbarEnabled(smoothScrollbar); 777 778 setChoiceMode(a.getInt(R.styleable.AbsListView_choiceMode, CHOICE_MODE_NONE)); 779 setFastScrollAlwaysVisible( 780 a.getBoolean(R.styleable.AbsListView_fastScrollAlwaysVisible, false)); 781 782 a.recycle(); 783 } 784 785 private void initAbsListView() { 786 // Setting focusable in touch mode will set the focusable property to true 787 setClickable(true); 788 setFocusableInTouchMode(true); 789 setWillNotDraw(false); 790 setAlwaysDrawnWithCacheEnabled(false); 791 setScrollingCacheEnabled(true); 792 793 final ViewConfiguration configuration = ViewConfiguration.get(mContext); 794 mTouchSlop = configuration.getScaledTouchSlop(); 795 mMinimumVelocity = configuration.getScaledMinimumFlingVelocity(); 796 mMaximumVelocity = configuration.getScaledMaximumFlingVelocity(); 797 mOverscrollDistance = configuration.getScaledOverscrollDistance(); 798 mOverflingDistance = configuration.getScaledOverflingDistance(); 799 800 mDensityScale = getContext().getResources().getDisplayMetrics().density; 801 } 802 803 @Override 804 public void setOverScrollMode(int mode) { 805 if (mode != OVER_SCROLL_NEVER) { 806 if (mEdgeGlowTop == null) { 807 Context context = getContext(); 808 mEdgeGlowTop = new EdgeEffect(context); 809 mEdgeGlowBottom = new EdgeEffect(context); 810 } 811 } else { 812 mEdgeGlowTop = null; 813 mEdgeGlowBottom = null; 814 } 815 super.setOverScrollMode(mode); 816 } 817 818 /** 819 * {@inheritDoc} 820 */ 821 @Override 822 public void setAdapter(ListAdapter adapter) { 823 if (adapter != null) { 824 mAdapterHasStableIds = mAdapter.hasStableIds(); 825 if (mChoiceMode != CHOICE_MODE_NONE && mAdapterHasStableIds && 826 mCheckedIdStates == null) { 827 mCheckedIdStates = new LongSparseArray<Integer>(); 828 } 829 } 830 831 if (mCheckStates != null) { 832 mCheckStates.clear(); 833 } 834 835 if (mCheckedIdStates != null) { 836 mCheckedIdStates.clear(); 837 } 838 } 839 840 /** 841 * Returns the number of items currently selected. This will only be valid 842 * if the choice mode is not {@link #CHOICE_MODE_NONE} (default). 843 * 844 * <p>To determine the specific items that are currently selected, use one of 845 * the <code>getChecked*</code> methods. 846 * 847 * @return The number of items currently selected 848 * 849 * @see #getCheckedItemPosition() 850 * @see #getCheckedItemPositions() 851 * @see #getCheckedItemIds() 852 */ 853 public int getCheckedItemCount() { 854 return mCheckedItemCount; 855 } 856 857 /** 858 * Returns the checked state of the specified position. The result is only 859 * valid if the choice mode has been set to {@link #CHOICE_MODE_SINGLE} 860 * or {@link #CHOICE_MODE_MULTIPLE}. 861 * 862 * @param position The item whose checked state to return 863 * @return The item's checked state or <code>false</code> if choice mode 864 * is invalid 865 * 866 * @see #setChoiceMode(int) 867 */ 868 public boolean isItemChecked(int position) { 869 if (mChoiceMode != CHOICE_MODE_NONE && mCheckStates != null) { 870 return mCheckStates.get(position); 871 } 872 873 return false; 874 } 875 876 /** 877 * Returns the currently checked item. The result is only valid if the choice 878 * mode has been set to {@link #CHOICE_MODE_SINGLE}. 879 * 880 * @return The position of the currently checked item or 881 * {@link #INVALID_POSITION} if nothing is selected 882 * 883 * @see #setChoiceMode(int) 884 */ 885 public int getCheckedItemPosition() { 886 if (mChoiceMode == CHOICE_MODE_SINGLE && mCheckStates != null && mCheckStates.size() == 1) { 887 return mCheckStates.keyAt(0); 888 } 889 890 return INVALID_POSITION; 891 } 892 893 /** 894 * Returns the set of checked items in the list. The result is only valid if 895 * the choice mode has not been set to {@link #CHOICE_MODE_NONE}. 896 * 897 * @return A SparseBooleanArray which will return true for each call to 898 * get(int position) where position is a position in the list, 899 * or <code>null</code> if the choice mode is set to 900 * {@link #CHOICE_MODE_NONE}. 901 */ 902 public SparseBooleanArray getCheckedItemPositions() { 903 if (mChoiceMode != CHOICE_MODE_NONE) { 904 return mCheckStates; 905 } 906 return null; 907 } 908 909 /** 910 * Returns the set of checked items ids. The result is only valid if the 911 * choice mode has not been set to {@link #CHOICE_MODE_NONE} and the adapter 912 * has stable IDs. ({@link ListAdapter#hasStableIds()} == {@code true}) 913 * 914 * @return A new array which contains the id of each checked item in the 915 * list. 916 */ 917 public long[] getCheckedItemIds() { 918 if (mChoiceMode == CHOICE_MODE_NONE || mCheckedIdStates == null || mAdapter == null) { 919 return new long[0]; 920 } 921 922 final LongSparseArray<Integer> idStates = mCheckedIdStates; 923 final int count = idStates.size(); 924 final long[] ids = new long[count]; 925 926 for (int i = 0; i < count; i++) { 927 ids[i] = idStates.keyAt(i); 928 } 929 930 return ids; 931 } 932 933 /** 934 * Clear any choices previously set 935 */ 936 public void clearChoices() { 937 if (mCheckStates != null) { 938 mCheckStates.clear(); 939 } 940 if (mCheckedIdStates != null) { 941 mCheckedIdStates.clear(); 942 } 943 mCheckedItemCount = 0; 944 } 945 946 /** 947 * Sets the checked state of the specified position. The is only valid if 948 * the choice mode has been set to {@link #CHOICE_MODE_SINGLE} or 949 * {@link #CHOICE_MODE_MULTIPLE}. 950 * 951 * @param position The item whose checked state is to be checked 952 * @param value The new checked state for the item 953 */ 954 public void setItemChecked(int position, boolean value) { 955 if (mChoiceMode == CHOICE_MODE_NONE) { 956 return; 957 } 958 959 // Start selection mode if needed. We don't need to if we're unchecking something. 960 if (value && mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL && mChoiceActionMode == null) { 961 mChoiceActionMode = startActionMode(mMultiChoiceModeCallback); 962 } 963 964 if (mChoiceMode == CHOICE_MODE_MULTIPLE || mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL) { 965 boolean oldValue = mCheckStates.get(position); 966 mCheckStates.put(position, value); 967 if (mCheckedIdStates != null && mAdapter.hasStableIds()) { 968 if (value) { 969 mCheckedIdStates.put(mAdapter.getItemId(position), position); 970 } else { 971 mCheckedIdStates.delete(mAdapter.getItemId(position)); 972 } 973 } 974 if (oldValue != value) { 975 if (value) { 976 mCheckedItemCount++; 977 } else { 978 mCheckedItemCount--; 979 } 980 } 981 if (mChoiceActionMode != null) { 982 final long id = mAdapter.getItemId(position); 983 mMultiChoiceModeCallback.onItemCheckedStateChanged(mChoiceActionMode, 984 position, id, value); 985 } 986 } else { 987 boolean updateIds = mCheckedIdStates != null && mAdapter.hasStableIds(); 988 // Clear all values if we're checking something, or unchecking the currently 989 // selected item 990 if (value || isItemChecked(position)) { 991 mCheckStates.clear(); 992 if (updateIds) { 993 mCheckedIdStates.clear(); 994 } 995 } 996 // this may end up selecting the value we just cleared but this way 997 // we ensure length of mCheckStates is 1, a fact getCheckedItemPosition relies on 998 if (value) { 999 mCheckStates.put(position, true); 1000 if (updateIds) { 1001 mCheckedIdStates.put(mAdapter.getItemId(position), position); 1002 } 1003 mCheckedItemCount = 1; 1004 } else if (mCheckStates.size() == 0 || !mCheckStates.valueAt(0)) { 1005 mCheckedItemCount = 0; 1006 } 1007 } 1008 1009 // Do not generate a data change while we are in the layout phase 1010 if (!mInLayout && !mBlockLayoutRequests) { 1011 mDataChanged = true; 1012 rememberSyncState(); 1013 requestLayout(); 1014 } 1015 } 1016 1017 @Override 1018 public boolean performItemClick(View view, int position, long id) { 1019 boolean handled = false; 1020 boolean dispatchItemClick = true; 1021 1022 if (mChoiceMode != CHOICE_MODE_NONE) { 1023 handled = true; 1024 boolean checkedStateChanged = false; 1025 1026 if (mChoiceMode == CHOICE_MODE_MULTIPLE || 1027 (mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL && mChoiceActionMode != null)) { 1028 boolean newValue = !mCheckStates.get(position, false); 1029 mCheckStates.put(position, newValue); 1030 if (mCheckedIdStates != null && mAdapter.hasStableIds()) { 1031 if (newValue) { 1032 mCheckedIdStates.put(mAdapter.getItemId(position), position); 1033 } else { 1034 mCheckedIdStates.delete(mAdapter.getItemId(position)); 1035 } 1036 } 1037 if (newValue) { 1038 mCheckedItemCount++; 1039 } else { 1040 mCheckedItemCount--; 1041 } 1042 if (mChoiceActionMode != null) { 1043 mMultiChoiceModeCallback.onItemCheckedStateChanged(mChoiceActionMode, 1044 position, id, newValue); 1045 dispatchItemClick = false; 1046 } 1047 checkedStateChanged = true; 1048 } else if (mChoiceMode == CHOICE_MODE_SINGLE) { 1049 boolean newValue = !mCheckStates.get(position, false); 1050 if (newValue) { 1051 mCheckStates.clear(); 1052 mCheckStates.put(position, true); 1053 if (mCheckedIdStates != null && mAdapter.hasStableIds()) { 1054 mCheckedIdStates.clear(); 1055 mCheckedIdStates.put(mAdapter.getItemId(position), position); 1056 } 1057 mCheckedItemCount = 1; 1058 } else if (mCheckStates.size() == 0 || !mCheckStates.valueAt(0)) { 1059 mCheckedItemCount = 0; 1060 } 1061 checkedStateChanged = true; 1062 } 1063 1064 if (checkedStateChanged) { 1065 updateOnScreenCheckedViews(); 1066 } 1067 } 1068 1069 if (dispatchItemClick) { 1070 handled |= super.performItemClick(view, position, id); 1071 } 1072 1073 return handled; 1074 } 1075 1076 /** 1077 * Perform a quick, in-place update of the checked or activated state 1078 * on all visible item views. This should only be called when a valid 1079 * choice mode is active. 1080 */ 1081 private void updateOnScreenCheckedViews() { 1082 final int firstPos = mFirstPosition; 1083 final int count = getChildCount(); 1084 final boolean useActivated = getContext().getApplicationInfo().targetSdkVersion 1085 >= android.os.Build.VERSION_CODES.HONEYCOMB; 1086 for (int i = 0; i < count; i++) { 1087 final View child = getChildAt(i); 1088 final int position = firstPos + i; 1089 1090 if (child instanceof Checkable) { 1091 ((Checkable) child).setChecked(mCheckStates.get(position)); 1092 } else if (useActivated) { 1093 child.setActivated(mCheckStates.get(position)); 1094 } 1095 } 1096 } 1097 1098 /** 1099 * @see #setChoiceMode(int) 1100 * 1101 * @return The current choice mode 1102 */ 1103 public int getChoiceMode() { 1104 return mChoiceMode; 1105 } 1106 1107 /** 1108 * Defines the choice behavior for the List. By default, Lists do not have any choice behavior 1109 * ({@link #CHOICE_MODE_NONE}). By setting the choiceMode to {@link #CHOICE_MODE_SINGLE}, the 1110 * List allows up to one item to be in a chosen state. By setting the choiceMode to 1111 * {@link #CHOICE_MODE_MULTIPLE}, the list allows any number of items to be chosen. 1112 * 1113 * @param choiceMode One of {@link #CHOICE_MODE_NONE}, {@link #CHOICE_MODE_SINGLE}, or 1114 * {@link #CHOICE_MODE_MULTIPLE} 1115 */ 1116 public void setChoiceMode(int choiceMode) { 1117 mChoiceMode = choiceMode; 1118 if (mChoiceActionMode != null) { 1119 mChoiceActionMode.finish(); 1120 mChoiceActionMode = null; 1121 } 1122 if (mChoiceMode != CHOICE_MODE_NONE) { 1123 if (mCheckStates == null) { 1124 mCheckStates = new SparseBooleanArray(); 1125 } 1126 if (mCheckedIdStates == null && mAdapter != null && mAdapter.hasStableIds()) { 1127 mCheckedIdStates = new LongSparseArray<Integer>(); 1128 } 1129 // Modal multi-choice mode only has choices when the mode is active. Clear them. 1130 if (mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL) { 1131 clearChoices(); 1132 setLongClickable(true); 1133 } 1134 } 1135 } 1136 1137 /** 1138 * Set a {@link MultiChoiceModeListener} that will manage the lifecycle of the 1139 * selection {@link ActionMode}. Only used when the choice mode is set to 1140 * {@link #CHOICE_MODE_MULTIPLE_MODAL}. 1141 * 1142 * @param listener Listener that will manage the selection mode 1143 * 1144 * @see #setChoiceMode(int) 1145 */ 1146 public void setMultiChoiceModeListener(MultiChoiceModeListener listener) { 1147 if (mMultiChoiceModeCallback == null) { 1148 mMultiChoiceModeCallback = new MultiChoiceModeWrapper(); 1149 } 1150 mMultiChoiceModeCallback.setWrapped(listener); 1151 } 1152 1153 /** 1154 * @return true if all list content currently fits within the view boundaries 1155 */ 1156 private boolean contentFits() { 1157 final int childCount = getChildCount(); 1158 if (childCount == 0) return true; 1159 if (childCount != mItemCount) return false; 1160 1161 return getChildAt(0).getTop() >= mListPadding.top && 1162 getChildAt(childCount - 1).getBottom() <= getHeight() - mListPadding.bottom; 1163 } 1164 1165 /** 1166 * Enables fast scrolling by letting the user quickly scroll through lists by 1167 * dragging the fast scroll thumb. The adapter attached to the list may want 1168 * to implement {@link SectionIndexer} if it wishes to display alphabet preview and 1169 * jump between sections of the list. 1170 * @see SectionIndexer 1171 * @see #isFastScrollEnabled() 1172 * @param enabled whether or not to enable fast scrolling 1173 */ 1174 public void setFastScrollEnabled(boolean enabled) { 1175 mFastScrollEnabled = enabled; 1176 if (enabled) { 1177 if (mFastScroller == null) { 1178 mFastScroller = new FastScroller(getContext(), this); 1179 } 1180 } else { 1181 if (mFastScroller != null) { 1182 mFastScroller.stop(); 1183 mFastScroller = null; 1184 } 1185 } 1186 } 1187 1188 /** 1189 * Set whether or not the fast scroller should always be shown in place of the 1190 * standard scrollbars. Fast scrollers shown in this way will not fade out and will 1191 * be a permanent fixture within the list. Best combined with an inset scroll bar style 1192 * that will ensure enough padding. This will enable fast scrolling if it is not 1193 * already enabled. 1194 * 1195 * @param alwaysShow true if the fast scroller should always be displayed. 1196 * @see #setScrollBarStyle(int) 1197 * @see #setFastScrollEnabled(boolean) 1198 */ 1199 public void setFastScrollAlwaysVisible(boolean alwaysShow) { 1200 if (alwaysShow && !mFastScrollEnabled) { 1201 setFastScrollEnabled(true); 1202 } 1203 1204 if (mFastScroller != null) { 1205 mFastScroller.setAlwaysShow(alwaysShow); 1206 } 1207 1208 computeOpaqueFlags(); 1209 recomputePadding(); 1210 } 1211 1212 /** 1213 * Returns true if the fast scroller is set to always show on this view rather than 1214 * fade out when not in use. 1215 * 1216 * @return true if the fast scroller will always show. 1217 * @see #setFastScrollAlwaysVisible(boolean) 1218 */ 1219 public boolean isFastScrollAlwaysVisible() { 1220 return mFastScrollEnabled && mFastScroller.isAlwaysShowEnabled(); 1221 } 1222 1223 @Override 1224 public int getVerticalScrollbarWidth() { 1225 if (isFastScrollAlwaysVisible()) { 1226 return Math.max(super.getVerticalScrollbarWidth(), mFastScroller.getWidth()); 1227 } 1228 return super.getVerticalScrollbarWidth(); 1229 } 1230 1231 /** 1232 * Returns the current state of the fast scroll feature. 1233 * @see #setFastScrollEnabled(boolean) 1234 * @return true if fast scroll is enabled, false otherwise 1235 */ 1236 @ViewDebug.ExportedProperty 1237 public boolean isFastScrollEnabled() { 1238 return mFastScrollEnabled; 1239 } 1240 1241 @Override 1242 public void setVerticalScrollbarPosition(int position) { 1243 super.setVerticalScrollbarPosition(position); 1244 if (mFastScroller != null) { 1245 mFastScroller.setScrollbarPosition(position); 1246 } 1247 } 1248 1249 /** 1250 * If fast scroll is visible, then don't draw the vertical scrollbar. 1251 * @hide 1252 */ 1253 @Override 1254 protected boolean isVerticalScrollBarHidden() { 1255 return mFastScroller != null && mFastScroller.isVisible(); 1256 } 1257 1258 /** 1259 * When smooth scrollbar is enabled, the position and size of the scrollbar thumb 1260 * is computed based on the number of visible pixels in the visible items. This 1261 * however assumes that all list items have the same height. If you use a list in 1262 * which items have different heights, the scrollbar will change appearance as the 1263 * user scrolls through the list. To avoid this issue, you need to disable this 1264 * property. 1265 * 1266 * When smooth scrollbar is disabled, the position and size of the scrollbar thumb 1267 * is based solely on the number of items in the adapter and the position of the 1268 * visible items inside the adapter. This provides a stable scrollbar as the user 1269 * navigates through a list of items with varying heights. 1270 * 1271 * @param enabled Whether or not to enable smooth scrollbar. 1272 * 1273 * @see #setSmoothScrollbarEnabled(boolean) 1274 * @attr ref android.R.styleable#AbsListView_smoothScrollbar 1275 */ 1276 public void setSmoothScrollbarEnabled(boolean enabled) { 1277 mSmoothScrollbarEnabled = enabled; 1278 } 1279 1280 /** 1281 * Returns the current state of the fast scroll feature. 1282 * 1283 * @return True if smooth scrollbar is enabled is enabled, false otherwise. 1284 * 1285 * @see #setSmoothScrollbarEnabled(boolean) 1286 */ 1287 @ViewDebug.ExportedProperty 1288 public boolean isSmoothScrollbarEnabled() { 1289 return mSmoothScrollbarEnabled; 1290 } 1291 1292 /** 1293 * Set the listener that will receive notifications every time the list scrolls. 1294 * 1295 * @param l the scroll listener 1296 */ 1297 public void setOnScrollListener(OnScrollListener l) { 1298 mOnScrollListener = l; 1299 invokeOnItemScrollListener(); 1300 } 1301 1302 /** 1303 * Notify our scroll listener (if there is one) of a change in scroll state 1304 */ 1305 void invokeOnItemScrollListener() { 1306 if (mFastScroller != null) { 1307 mFastScroller.onScroll(this, mFirstPosition, getChildCount(), mItemCount); 1308 } 1309 if (mOnScrollListener != null) { 1310 mOnScrollListener.onScroll(this, mFirstPosition, getChildCount(), mItemCount); 1311 } 1312 onScrollChanged(0, 0, 0, 0); // dummy values, View's implementation does not use these. 1313 } 1314 1315 @Override 1316 public void sendAccessibilityEvent(int eventType) { 1317 // Since this class calls onScrollChanged even if the mFirstPosition and the 1318 // child count have not changed we will avoid sending duplicate accessibility 1319 // events. 1320 if (eventType == AccessibilityEvent.TYPE_VIEW_SCROLLED) { 1321 final int firstVisiblePosition = getFirstVisiblePosition(); 1322 final int lastVisiblePosition = getLastVisiblePosition(); 1323 if (mLastAccessibilityScrollEventFromIndex == firstVisiblePosition 1324 && mLastAccessibilityScrollEventToIndex == lastVisiblePosition) { 1325 return; 1326 } else { 1327 mLastAccessibilityScrollEventFromIndex = firstVisiblePosition; 1328 mLastAccessibilityScrollEventToIndex = lastVisiblePosition; 1329 } 1330 } 1331 super.sendAccessibilityEvent(eventType); 1332 } 1333 1334 @Override 1335 public void onInitializeAccessibilityEvent(AccessibilityEvent event) { 1336 super.onInitializeAccessibilityEvent(event); 1337 event.setClassName(AbsListView.class.getName()); 1338 } 1339 1340 @Override 1341 public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) { 1342 super.onInitializeAccessibilityNodeInfo(info); 1343 info.setClassName(AbsListView.class.getName()); 1344 } 1345 1346 /** 1347 * Indicates whether the children's drawing cache is used during a scroll. 1348 * By default, the drawing cache is enabled but this will consume more memory. 1349 * 1350 * @return true if the scrolling cache is enabled, false otherwise 1351 * 1352 * @see #setScrollingCacheEnabled(boolean) 1353 * @see View#setDrawingCacheEnabled(boolean) 1354 */ 1355 @ViewDebug.ExportedProperty 1356 public boolean isScrollingCacheEnabled() { 1357 return mScrollingCacheEnabled; 1358 } 1359 1360 /** 1361 * Enables or disables the children's drawing cache during a scroll. 1362 * By default, the drawing cache is enabled but this will use more memory. 1363 * 1364 * When the scrolling cache is enabled, the caches are kept after the 1365 * first scrolling. You can manually clear the cache by calling 1366 * {@link android.view.ViewGroup#setChildrenDrawingCacheEnabled(boolean)}. 1367 * 1368 * @param enabled true to enable the scroll cache, false otherwise 1369 * 1370 * @see #isScrollingCacheEnabled() 1371 * @see View#setDrawingCacheEnabled(boolean) 1372 */ 1373 public void setScrollingCacheEnabled(boolean enabled) { 1374 if (mScrollingCacheEnabled && !enabled) { 1375 clearScrollingCache(); 1376 } 1377 mScrollingCacheEnabled = enabled; 1378 } 1379 1380 /** 1381 * Enables or disables the type filter window. If enabled, typing when 1382 * this view has focus will filter the children to match the users input. 1383 * Note that the {@link Adapter} used by this view must implement the 1384 * {@link Filterable} interface. 1385 * 1386 * @param textFilterEnabled true to enable type filtering, false otherwise 1387 * 1388 * @see Filterable 1389 */ 1390 public void setTextFilterEnabled(boolean textFilterEnabled) { 1391 mTextFilterEnabled = textFilterEnabled; 1392 } 1393 1394 /** 1395 * Indicates whether type filtering is enabled for this view 1396 * 1397 * @return true if type filtering is enabled, false otherwise 1398 * 1399 * @see #setTextFilterEnabled(boolean) 1400 * @see Filterable 1401 */ 1402 @ViewDebug.ExportedProperty 1403 public boolean isTextFilterEnabled() { 1404 return mTextFilterEnabled; 1405 } 1406 1407 @Override 1408 public void getFocusedRect(Rect r) { 1409 View view = getSelectedView(); 1410 if (view != null && view.getParent() == this) { 1411 // the focused rectangle of the selected view offset into the 1412 // coordinate space of this view. 1413 view.getFocusedRect(r); 1414 offsetDescendantRectToMyCoords(view, r); 1415 } else { 1416 // otherwise, just the norm 1417 super.getFocusedRect(r); 1418 } 1419 } 1420 1421 private void useDefaultSelector() { 1422 setSelector(getResources().getDrawable( 1423 com.android.internal.R.drawable.list_selector_background)); 1424 } 1425 1426 /** 1427 * Indicates whether the content of this view is pinned to, or stacked from, 1428 * the bottom edge. 1429 * 1430 * @return true if the content is stacked from the bottom edge, false otherwise 1431 */ 1432 @ViewDebug.ExportedProperty 1433 public boolean isStackFromBottom() { 1434 return mStackFromBottom; 1435 } 1436 1437 /** 1438 * When stack from bottom is set to true, the list fills its content starting from 1439 * the bottom of the view. 1440 * 1441 * @param stackFromBottom true to pin the view's content to the bottom edge, 1442 * false to pin the view's content to the top edge 1443 */ 1444 public void setStackFromBottom(boolean stackFromBottom) { 1445 if (mStackFromBottom != stackFromBottom) { 1446 mStackFromBottom = stackFromBottom; 1447 requestLayoutIfNecessary(); 1448 } 1449 } 1450 1451 void requestLayoutIfNecessary() { 1452 if (getChildCount() > 0) { 1453 resetList(); 1454 requestLayout(); 1455 invalidate(); 1456 } 1457 } 1458 1459 static class SavedState extends BaseSavedState { 1460 long selectedId; 1461 long firstId; 1462 int viewTop; 1463 int position; 1464 int height; 1465 String filter; 1466 boolean inActionMode; 1467 int checkedItemCount; 1468 SparseBooleanArray checkState; 1469 LongSparseArray<Integer> checkIdState; 1470 1471 /** 1472 * Constructor called from {@link AbsListView#onSaveInstanceState()} 1473 */ 1474 SavedState(Parcelable superState) { 1475 super(superState); 1476 } 1477 1478 /** 1479 * Constructor called from {@link #CREATOR} 1480 */ 1481 private SavedState(Parcel in) { 1482 super(in); 1483 selectedId = in.readLong(); 1484 firstId = in.readLong(); 1485 viewTop = in.readInt(); 1486 position = in.readInt(); 1487 height = in.readInt(); 1488 filter = in.readString(); 1489 inActionMode = in.readByte() != 0; 1490 checkedItemCount = in.readInt(); 1491 checkState = in.readSparseBooleanArray(); 1492 final int N = in.readInt(); 1493 if (N > 0) { 1494 checkIdState = new LongSparseArray<Integer>(); 1495 for (int i=0; i<N; i++) { 1496 final long key = in.readLong(); 1497 final int value = in.readInt(); 1498 checkIdState.put(key, value); 1499 } 1500 } 1501 } 1502 1503 @Override 1504 public void writeToParcel(Parcel out, int flags) { 1505 super.writeToParcel(out, flags); 1506 out.writeLong(selectedId); 1507 out.writeLong(firstId); 1508 out.writeInt(viewTop); 1509 out.writeInt(position); 1510 out.writeInt(height); 1511 out.writeString(filter); 1512 out.writeByte((byte) (inActionMode ? 1 : 0)); 1513 out.writeInt(checkedItemCount); 1514 out.writeSparseBooleanArray(checkState); 1515 final int N = checkIdState != null ? checkIdState.size() : 0; 1516 out.writeInt(N); 1517 for (int i=0; i<N; i++) { 1518 out.writeLong(checkIdState.keyAt(i)); 1519 out.writeInt(checkIdState.valueAt(i)); 1520 } 1521 } 1522 1523 @Override 1524 public String toString() { 1525 return "AbsListView.SavedState{" 1526 + Integer.toHexString(System.identityHashCode(this)) 1527 + " selectedId=" + selectedId 1528 + " firstId=" + firstId 1529 + " viewTop=" + viewTop 1530 + " position=" + position 1531 + " height=" + height 1532 + " filter=" + filter 1533 + " checkState=" + checkState + "}"; 1534 } 1535 1536 public static final Parcelable.Creator<SavedState> CREATOR 1537 = new Parcelable.Creator<SavedState>() { 1538 public SavedState createFromParcel(Parcel in) { 1539 return new SavedState(in); 1540 } 1541 1542 public SavedState[] newArray(int size) { 1543 return new SavedState[size]; 1544 } 1545 }; 1546 } 1547 1548 @Override 1549 public Parcelable onSaveInstanceState() { 1550 /* 1551 * This doesn't really make sense as the place to dismiss the 1552 * popups, but there don't seem to be any other useful hooks 1553 * that happen early enough to keep from getting complaints 1554 * about having leaked the window. 1555 */ 1556 dismissPopup(); 1557 1558 Parcelable superState = super.onSaveInstanceState(); 1559 1560 SavedState ss = new SavedState(superState); 1561 1562 boolean haveChildren = getChildCount() > 0 && mItemCount > 0; 1563 long selectedId = getSelectedItemId(); 1564 ss.selectedId = selectedId; 1565 ss.height = getHeight(); 1566 1567 if (selectedId >= 0) { 1568 // Remember the selection 1569 ss.viewTop = mSelectedTop; 1570 ss.position = getSelectedItemPosition(); 1571 ss.firstId = INVALID_POSITION; 1572 } else { 1573 if (haveChildren && mFirstPosition > 0) { 1574 // Remember the position of the first child. 1575 // We only do this if we are not currently at the top of 1576 // the list, for two reasons: 1577 // (1) The list may be in the process of becoming empty, in 1578 // which case mItemCount may not be 0, but if we try to 1579 // ask for any information about position 0 we will crash. 1580 // (2) Being "at the top" seems like a special case, anyway, 1581 // and the user wouldn't expect to end up somewhere else when 1582 // they revisit the list even if its content has changed. 1583 View v = getChildAt(0); 1584 ss.viewTop = v.getTop(); 1585 int firstPos = mFirstPosition; 1586 if (firstPos >= mItemCount) { 1587 firstPos = mItemCount - 1; 1588 } 1589 ss.position = firstPos; 1590 ss.firstId = mAdapter.getItemId(firstPos); 1591 } else { 1592 ss.viewTop = 0; 1593 ss.firstId = INVALID_POSITION; 1594 ss.position = 0; 1595 } 1596 } 1597 1598 ss.filter = null; 1599 if (mFiltered) { 1600 final EditText textFilter = mTextFilter; 1601 if (textFilter != null) { 1602 Editable filterText = textFilter.getText(); 1603 if (filterText != null) { 1604 ss.filter = filterText.toString(); 1605 } 1606 } 1607 } 1608 1609 ss.inActionMode = mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL && mChoiceActionMode != null; 1610 1611 if (mCheckStates != null) { 1612 ss.checkState = mCheckStates.clone(); 1613 } 1614 if (mCheckedIdStates != null) { 1615 final LongSparseArray<Integer> idState = new LongSparseArray<Integer>(); 1616 final int count = mCheckedIdStates.size(); 1617 for (int i = 0; i < count; i++) { 1618 idState.put(mCheckedIdStates.keyAt(i), mCheckedIdStates.valueAt(i)); 1619 } 1620 ss.checkIdState = idState; 1621 } 1622 ss.checkedItemCount = mCheckedItemCount; 1623 1624 return ss; 1625 } 1626 1627 @Override 1628 public void onRestoreInstanceState(Parcelable state) { 1629 SavedState ss = (SavedState) state; 1630 1631 super.onRestoreInstanceState(ss.getSuperState()); 1632 mDataChanged = true; 1633 1634 mSyncHeight = ss.height; 1635 1636 if (ss.selectedId >= 0) { 1637 mNeedSync = true; 1638 mSyncRowId = ss.selectedId; 1639 mSyncPosition = ss.position; 1640 mSpecificTop = ss.viewTop; 1641 mSyncMode = SYNC_SELECTED_POSITION; 1642 } else if (ss.firstId >= 0) { 1643 setSelectedPositionInt(INVALID_POSITION); 1644 // Do this before setting mNeedSync since setNextSelectedPosition looks at mNeedSync 1645 setNextSelectedPositionInt(INVALID_POSITION); 1646 mSelectorPosition = INVALID_POSITION; 1647 mNeedSync = true; 1648 mSyncRowId = ss.firstId; 1649 mSyncPosition = ss.position; 1650 mSpecificTop = ss.viewTop; 1651 mSyncMode = SYNC_FIRST_POSITION; 1652 } 1653 1654 setFilterText(ss.filter); 1655 1656 if (ss.checkState != null) { 1657 mCheckStates = ss.checkState; 1658 } 1659 1660 if (ss.checkIdState != null) { 1661 mCheckedIdStates = ss.checkIdState; 1662 } 1663 1664 mCheckedItemCount = ss.checkedItemCount; 1665 1666 if (ss.inActionMode && mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL && 1667 mMultiChoiceModeCallback != null) { 1668 mChoiceActionMode = startActionMode(mMultiChoiceModeCallback); 1669 } 1670 1671 requestLayout(); 1672 } 1673 1674 private boolean acceptFilter() { 1675 return mTextFilterEnabled && getAdapter() instanceof Filterable && 1676 ((Filterable) getAdapter()).getFilter() != null; 1677 } 1678 1679 /** 1680 * Sets the initial value for the text filter. 1681 * @param filterText The text to use for the filter. 1682 * 1683 * @see #setTextFilterEnabled 1684 */ 1685 public void setFilterText(String filterText) { 1686 // TODO: Should we check for acceptFilter()? 1687 if (mTextFilterEnabled && !TextUtils.isEmpty(filterText)) { 1688 createTextFilter(false); 1689 // This is going to call our listener onTextChanged, but we might not 1690 // be ready to bring up a window yet 1691 mTextFilter.setText(filterText); 1692 mTextFilter.setSelection(filterText.length()); 1693 if (mAdapter instanceof Filterable) { 1694 // if mPopup is non-null, then onTextChanged will do the filtering 1695 if (mPopup == null) { 1696 Filter f = ((Filterable) mAdapter).getFilter(); 1697 f.filter(filterText); 1698 } 1699 // Set filtered to true so we will display the filter window when our main 1700 // window is ready 1701 mFiltered = true; 1702 mDataSetObserver.clearSavedState(); 1703 } 1704 } 1705 } 1706 1707 /** 1708 * Returns the list's text filter, if available. 1709 * @return the list's text filter or null if filtering isn't enabled 1710 */ 1711 public CharSequence getTextFilter() { 1712 if (mTextFilterEnabled && mTextFilter != null) { 1713 return mTextFilter.getText(); 1714 } 1715 return null; 1716 } 1717 1718 @Override 1719 protected void onFocusChanged(boolean gainFocus, int direction, Rect previouslyFocusedRect) { 1720 super.onFocusChanged(gainFocus, direction, previouslyFocusedRect); 1721 if (gainFocus && mSelectedPosition < 0 && !isInTouchMode()) { 1722 if (!mIsAttached && mAdapter != null) { 1723 // Data may have changed while we were detached and it's valid 1724 // to change focus while detached. Refresh so we don't die. 1725 mDataChanged = true; 1726 mOldItemCount = mItemCount; 1727 mItemCount = mAdapter.getCount(); 1728 } 1729 resurrectSelection(); 1730 } 1731 } 1732 1733 @Override 1734 public void requestLayout() { 1735 if (!mBlockLayoutRequests && !mInLayout) { 1736 super.requestLayout(); 1737 } 1738 } 1739 1740 /** 1741 * The list is empty. Clear everything out. 1742 */ 1743 void resetList() { 1744 removeAllViewsInLayout(); 1745 mFirstPosition = 0; 1746 mDataChanged = false; 1747 mNeedSync = false; 1748 mOldSelectedPosition = INVALID_POSITION; 1749 mOldSelectedRowId = INVALID_ROW_ID; 1750 setSelectedPositionInt(INVALID_POSITION); 1751 setNextSelectedPositionInt(INVALID_POSITION); 1752 mSelectedTop = 0; 1753 mSelectorPosition = INVALID_POSITION; 1754 mSelectorRect.setEmpty(); 1755 invalidate(); 1756 } 1757 1758 @Override 1759 protected int computeVerticalScrollExtent() { 1760 final int count = getChildCount(); 1761 if (count > 0) { 1762 if (mSmoothScrollbarEnabled) { 1763 int extent = count * 100; 1764 1765 View view = getChildAt(0); 1766 final int top = view.getTop(); 1767 int height = view.getHeight(); 1768 if (height > 0) { 1769 extent += (top * 100) / height; 1770 } 1771 1772 view = getChildAt(count - 1); 1773 final int bottom = view.getBottom(); 1774 height = view.getHeight(); 1775 if (height > 0) { 1776 extent -= ((bottom - getHeight()) * 100) / height; 1777 } 1778 1779 return extent; 1780 } else { 1781 return 1; 1782 } 1783 } 1784 return 0; 1785 } 1786 1787 @Override 1788 protected int computeVerticalScrollOffset() { 1789 final int firstPosition = mFirstPosition; 1790 final int childCount = getChildCount(); 1791 if (firstPosition >= 0 && childCount > 0) { 1792 if (mSmoothScrollbarEnabled) { 1793 final View view = getChildAt(0); 1794 final int top = view.getTop(); 1795 int height = view.getHeight(); 1796 if (height > 0) { 1797 return Math.max(firstPosition * 100 - (top * 100) / height + 1798 (int)((float)mScrollY / getHeight() * mItemCount * 100), 0); 1799 } 1800 } else { 1801 int index; 1802 final int count = mItemCount; 1803 if (firstPosition == 0) { 1804 index = 0; 1805 } else if (firstPosition + childCount == count) { 1806 index = count; 1807 } else { 1808 index = firstPosition + childCount / 2; 1809 } 1810 return (int) (firstPosition + childCount * (index / (float) count)); 1811 } 1812 } 1813 return 0; 1814 } 1815 1816 @Override 1817 protected int computeVerticalScrollRange() { 1818 int result; 1819 if (mSmoothScrollbarEnabled) { 1820 result = Math.max(mItemCount * 100, 0); 1821 if (mScrollY != 0) { 1822 // Compensate for overscroll 1823 result += Math.abs((int) ((float) mScrollY / getHeight() * mItemCount * 100)); 1824 } 1825 } else { 1826 result = mItemCount; 1827 } 1828 return result; 1829 } 1830 1831 @Override 1832 protected float getTopFadingEdgeStrength() { 1833 final int count = getChildCount(); 1834 final float fadeEdge = super.getTopFadingEdgeStrength(); 1835 if (count == 0) { 1836 return fadeEdge; 1837 } else { 1838 if (mFirstPosition > 0) { 1839 return 1.0f; 1840 } 1841 1842 final int top = getChildAt(0).getTop(); 1843 final float fadeLength = (float) getVerticalFadingEdgeLength(); 1844 return top < mPaddingTop ? (float) -(top - mPaddingTop) / fadeLength : fadeEdge; 1845 } 1846 } 1847 1848 @Override 1849 protected float getBottomFadingEdgeStrength() { 1850 final int count = getChildCount(); 1851 final float fadeEdge = super.getBottomFadingEdgeStrength(); 1852 if (count == 0) { 1853 return fadeEdge; 1854 } else { 1855 if (mFirstPosition + count - 1 < mItemCount - 1) { 1856 return 1.0f; 1857 } 1858 1859 final int bottom = getChildAt(count - 1).getBottom(); 1860 final int height = getHeight(); 1861 final float fadeLength = (float) getVerticalFadingEdgeLength(); 1862 return bottom > height - mPaddingBottom ? 1863 (float) (bottom - height + mPaddingBottom) / fadeLength : fadeEdge; 1864 } 1865 } 1866 1867 @Override 1868 protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { 1869 if (mSelector == null) { 1870 useDefaultSelector(); 1871 } 1872 final Rect listPadding = mListPadding; 1873 listPadding.left = mSelectionLeftPadding + mPaddingLeft; 1874 listPadding.top = mSelectionTopPadding + mPaddingTop; 1875 listPadding.right = mSelectionRightPadding + mPaddingRight; 1876 listPadding.bottom = mSelectionBottomPadding + mPaddingBottom; 1877 1878 // Check if our previous measured size was at a point where we should scroll later. 1879 if (mTranscriptMode == TRANSCRIPT_MODE_NORMAL) { 1880 final int childCount = getChildCount(); 1881 final int listBottom = getHeight() - getPaddingBottom(); 1882 final View lastChild = getChildAt(childCount - 1); 1883 final int lastBottom = lastChild != null ? lastChild.getBottom() : listBottom; 1884 mForceTranscriptScroll = mFirstPosition + childCount >= mLastHandledItemCount && 1885 lastBottom <= listBottom; 1886 } 1887 } 1888 1889 /** 1890 * Subclasses should NOT override this method but 1891 * {@link #layoutChildren()} instead. 1892 */ 1893 @Override 1894 protected void onLayout(boolean changed, int l, int t, int r, int b) { 1895 super.onLayout(changed, l, t, r, b); 1896 mInLayout = true; 1897 if (changed) { 1898 int childCount = getChildCount(); 1899 for (int i = 0; i < childCount; i++) { 1900 getChildAt(i).forceLayout(); 1901 } 1902 mRecycler.markChildrenDirty(); 1903 } 1904 1905 if (mFastScroller != null && mItemCount != mOldItemCount) { 1906 mFastScroller.onItemCountChanged(mOldItemCount, mItemCount); 1907 } 1908 1909 layoutChildren(); 1910 mInLayout = false; 1911 1912 mOverscrollMax = (b - t) / OVERSCROLL_LIMIT_DIVISOR; 1913 } 1914 1915 /** 1916 * @hide 1917 */ 1918 @Override 1919 protected boolean setFrame(int left, int top, int right, int bottom) { 1920 final boolean changed = super.setFrame(left, top, right, bottom); 1921 1922 if (changed) { 1923 // Reposition the popup when the frame has changed. This includes 1924 // translating the widget, not just changing its dimension. The 1925 // filter popup needs to follow the widget. 1926 final boolean visible = getWindowVisibility() == View.VISIBLE; 1927 if (mFiltered && visible && mPopup != null && mPopup.isShowing()) { 1928 positionPopup(); 1929 } 1930 } 1931 1932 return changed; 1933 } 1934 1935 /** 1936 * Subclasses must override this method to layout their children. 1937 */ 1938 protected void layoutChildren() { 1939 } 1940 1941 void updateScrollIndicators() { 1942 if (mScrollUp != null) { 1943 boolean canScrollUp; 1944 // 0th element is not visible 1945 canScrollUp = mFirstPosition > 0; 1946 1947 // ... Or top of 0th element is not visible 1948 if (!canScrollUp) { 1949 if (getChildCount() > 0) { 1950 View child = getChildAt(0); 1951 canScrollUp = child.getTop() < mListPadding.top; 1952 } 1953 } 1954 1955 mScrollUp.setVisibility(canScrollUp ? View.VISIBLE : View.INVISIBLE); 1956 } 1957 1958 if (mScrollDown != null) { 1959 boolean canScrollDown; 1960 int count = getChildCount(); 1961 1962 // Last item is not visible 1963 canScrollDown = (mFirstPosition + count) < mItemCount; 1964 1965 // ... Or bottom of the last element is not visible 1966 if (!canScrollDown && count > 0) { 1967 View child = getChildAt(count - 1); 1968 canScrollDown = child.getBottom() > mBottom - mListPadding.bottom; 1969 } 1970 1971 mScrollDown.setVisibility(canScrollDown ? View.VISIBLE : View.INVISIBLE); 1972 } 1973 } 1974 1975 @Override 1976 @ViewDebug.ExportedProperty 1977 public View getSelectedView() { 1978 if (mItemCount > 0 && mSelectedPosition >= 0) { 1979 return getChildAt(mSelectedPosition - mFirstPosition); 1980 } else { 1981 return null; 1982 } 1983 } 1984 1985 /** 1986 * List padding is the maximum of the normal view's padding and the padding of the selector. 1987 * 1988 * @see android.view.View#getPaddingTop() 1989 * @see #getSelector() 1990 * 1991 * @return The top list padding. 1992 */ 1993 public int getListPaddingTop() { 1994 return mListPadding.top; 1995 } 1996 1997 /** 1998 * List padding is the maximum of the normal view's padding and the padding of the selector. 1999 * 2000 * @see android.view.View#getPaddingBottom() 2001 * @see #getSelector() 2002 * 2003 * @return The bottom list padding. 2004 */ 2005 public int getListPaddingBottom() { 2006 return mListPadding.bottom; 2007 } 2008 2009 /** 2010 * List padding is the maximum of the normal view's padding and the padding of the selector. 2011 * 2012 * @see android.view.View#getPaddingLeft() 2013 * @see #getSelector() 2014 * 2015 * @return The left list padding. 2016 */ 2017 public int getListPaddingLeft() { 2018 return mListPadding.left; 2019 } 2020 2021 /** 2022 * List padding is the maximum of the normal view's padding and the padding of the selector. 2023 * 2024 * @see android.view.View#getPaddingRight() 2025 * @see #getSelector() 2026 * 2027 * @return The right list padding. 2028 */ 2029 public int getListPaddingRight() { 2030 return mListPadding.right; 2031 } 2032 2033 /** 2034 * Get a view and have it show the data associated with the specified 2035 * position. This is called when we have already discovered that the view is 2036 * not available for reuse in the recycle bin. The only choices left are 2037 * converting an old view or making a new one. 2038 * 2039 * @param position The position to display 2040 * @param isScrap Array of at least 1 boolean, the first entry will become true if 2041 * the returned view was taken from the scrap heap, false if otherwise. 2042 * 2043 * @return A view displaying the data associated with the specified position 2044 */ 2045 View obtainView(int position, boolean[] isScrap) { 2046 isScrap[0] = false; 2047 View scrapView; 2048 2049 scrapView = mRecycler.getTransientStateView(position); 2050 if (scrapView != null) { 2051 return scrapView; 2052 } 2053 2054 scrapView = mRecycler.getScrapView(position); 2055 2056 View child; 2057 if (scrapView != null) { 2058 if (ViewDebug.TRACE_RECYCLER) { 2059 ViewDebug.trace(scrapView, ViewDebug.RecyclerTraceType.RECYCLE_FROM_SCRAP_HEAP, 2060 position, -1); 2061 } 2062 2063 child = mAdapter.getView(position, scrapView, this); 2064 2065 if (ViewDebug.TRACE_RECYCLER) { 2066 ViewDebug.trace(child, ViewDebug.RecyclerTraceType.BIND_VIEW, 2067 position, getChildCount()); 2068 } 2069 2070 if (child != scrapView) { 2071 mRecycler.addScrapView(scrapView, position); 2072 if (mCacheColorHint != 0) { 2073 child.setDrawingCacheBackgroundColor(mCacheColorHint); 2074 } 2075 if (ViewDebug.TRACE_RECYCLER) { 2076 ViewDebug.trace(scrapView, ViewDebug.RecyclerTraceType.MOVE_TO_SCRAP_HEAP, 2077 position, -1); 2078 } 2079 } else { 2080 isScrap[0] = true; 2081 child.dispatchFinishTemporaryDetach(); 2082 } 2083 } else { 2084 child = mAdapter.getView(position, null, this); 2085 if (mCacheColorHint != 0) { 2086 child.setDrawingCacheBackgroundColor(mCacheColorHint); 2087 } 2088 if (ViewDebug.TRACE_RECYCLER) { 2089 ViewDebug.trace(child, ViewDebug.RecyclerTraceType.NEW_VIEW, 2090 position, getChildCount()); 2091 } 2092 } 2093 2094 if (mAdapterHasStableIds) { 2095 final ViewGroup.LayoutParams vlp = child.getLayoutParams(); 2096 LayoutParams lp; 2097 if (vlp == null) { 2098 lp = (LayoutParams) generateDefaultLayoutParams(); 2099 } else if (!checkLayoutParams(vlp)) { 2100 lp = (LayoutParams) generateLayoutParams(vlp); 2101 } else { 2102 lp = (LayoutParams) vlp; 2103 } 2104 lp.itemId = mAdapter.getItemId(position); 2105 child.setLayoutParams(lp); 2106 } 2107 2108 return child; 2109 } 2110 2111 void positionSelector(int position, View sel) { 2112 if (position != INVALID_POSITION) { 2113 mSelectorPosition = position; 2114 } 2115 2116 final Rect selectorRect = mSelectorRect; 2117 selectorRect.set(sel.getLeft(), sel.getTop(), sel.getRight(), sel.getBottom()); 2118 if (sel instanceof SelectionBoundsAdjuster) { 2119 ((SelectionBoundsAdjuster)sel).adjustListItemSelectionBounds(selectorRect); 2120 } 2121 positionSelector(selectorRect.left, selectorRect.top, selectorRect.right, 2122 selectorRect.bottom); 2123 2124 final boolean isChildViewEnabled = mIsChildViewEnabled; 2125 if (sel.isEnabled() != isChildViewEnabled) { 2126 mIsChildViewEnabled = !isChildViewEnabled; 2127 if (getSelectedItemPosition() != INVALID_POSITION) { 2128 refreshDrawableState(); 2129 } 2130 } 2131 } 2132 2133 private void positionSelector(int l, int t, int r, int b) { 2134 mSelectorRect.set(l - mSelectionLeftPadding, t - mSelectionTopPadding, r 2135 + mSelectionRightPadding, b + mSelectionBottomPadding); 2136 } 2137 2138 @Override 2139 protected void dispatchDraw(Canvas canvas) { 2140 int saveCount = 0; 2141 final boolean clipToPadding = (mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK; 2142 if (clipToPadding) { 2143 saveCount = canvas.save(); 2144 final int scrollX = mScrollX; 2145 final int scrollY = mScrollY; 2146 canvas.clipRect(scrollX + mPaddingLeft, scrollY + mPaddingTop, 2147 scrollX + mRight - mLeft - mPaddingRight, 2148 scrollY + mBottom - mTop - mPaddingBottom); 2149 mGroupFlags &= ~CLIP_TO_PADDING_MASK; 2150 } 2151 2152 final boolean drawSelectorOnTop = mDrawSelectorOnTop; 2153 if (!drawSelectorOnTop) { 2154 drawSelector(canvas); 2155 } 2156 2157 super.dispatchDraw(canvas); 2158 2159 if (drawSelectorOnTop) { 2160 drawSelector(canvas); 2161 } 2162 2163 if (clipToPadding) { 2164 canvas.restoreToCount(saveCount); 2165 mGroupFlags |= CLIP_TO_PADDING_MASK; 2166 } 2167 } 2168 2169 @Override 2170 protected boolean isPaddingOffsetRequired() { 2171 return (mGroupFlags & CLIP_TO_PADDING_MASK) != CLIP_TO_PADDING_MASK; 2172 } 2173 2174 @Override 2175 protected int getLeftPaddingOffset() { 2176 return (mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK ? 0 : -mPaddingLeft; 2177 } 2178 2179 @Override 2180 protected int getTopPaddingOffset() { 2181 return (mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK ? 0 : -mPaddingTop; 2182 } 2183 2184 @Override 2185 protected int getRightPaddingOffset() { 2186 return (mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK ? 0 : mPaddingRight; 2187 } 2188 2189 @Override 2190 protected int getBottomPaddingOffset() { 2191 return (mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK ? 0 : mPaddingBottom; 2192 } 2193 2194 @Override 2195 protected void onSizeChanged(int w, int h, int oldw, int oldh) { 2196 if (getChildCount() > 0) { 2197 mDataChanged = true; 2198 rememberSyncState(); 2199 } 2200 2201 if (mFastScroller != null) { 2202 mFastScroller.onSizeChanged(w, h, oldw, oldh); 2203 } 2204 } 2205 2206 /** 2207 * @return True if the current touch mode requires that we draw the selector in the pressed 2208 * state. 2209 */ 2210 boolean touchModeDrawsInPressedState() { 2211 // FIXME use isPressed for this 2212 switch (mTouchMode) { 2213 case TOUCH_MODE_TAP: 2214 case TOUCH_MODE_DONE_WAITING: 2215 return true; 2216 default: 2217 return false; 2218 } 2219 } 2220 2221 /** 2222 * Indicates whether this view is in a state where the selector should be drawn. This will 2223 * happen if we have focus but are not in touch mode, or we are in the middle of displaying 2224 * the pressed state for an item. 2225 * 2226 * @return True if the selector should be shown 2227 */ 2228 boolean shouldShowSelector() { 2229 return (hasFocus() && !isInTouchMode()) || touchModeDrawsInPressedState(); 2230 } 2231 2232 private void drawSelector(Canvas canvas) { 2233 if (!mSelectorRect.isEmpty()) { 2234 final Drawable selector = mSelector; 2235 selector.setBounds(mSelectorRect); 2236 selector.draw(canvas); 2237 } 2238 } 2239 2240 /** 2241 * Controls whether the selection highlight drawable should be drawn on top of the item or 2242 * behind it. 2243 * 2244 * @param onTop If true, the selector will be drawn on the item it is highlighting. The default 2245 * is false. 2246 * 2247 * @attr ref android.R.styleable#AbsListView_drawSelectorOnTop 2248 */ 2249 public void setDrawSelectorOnTop(boolean onTop) { 2250 mDrawSelectorOnTop = onTop; 2251 } 2252 2253 /** 2254 * Set a Drawable that should be used to highlight the currently selected item. 2255 * 2256 * @param resID A Drawable resource to use as the selection highlight. 2257 * 2258 * @attr ref android.R.styleable#AbsListView_listSelector 2259 */ 2260 public void setSelector(int resID) { 2261 setSelector(getResources().getDrawable(resID)); 2262 } 2263 2264 public void setSelector(Drawable sel) { 2265 if (mSelector != null) { 2266 mSelector.setCallback(null); 2267 unscheduleDrawable(mSelector); 2268 } 2269 mSelector = sel; 2270 Rect padding = new Rect(); 2271 sel.getPadding(padding); 2272 mSelectionLeftPadding = padding.left; 2273 mSelectionTopPadding = padding.top; 2274 mSelectionRightPadding = padding.right; 2275 mSelectionBottomPadding = padding.bottom; 2276 sel.setCallback(this); 2277 updateSelectorState(); 2278 } 2279 2280 /** 2281 * Returns the selector {@link android.graphics.drawable.Drawable} that is used to draw the 2282 * selection in the list. 2283 * 2284 * @return the drawable used to display the selector 2285 */ 2286 public Drawable getSelector() { 2287 return mSelector; 2288 } 2289 2290 /** 2291 * Sets the selector state to "pressed" and posts a CheckForKeyLongPress to see if 2292 * this is a long press. 2293 */ 2294 void keyPressed() { 2295 if (!isEnabled() || !isClickable()) { 2296 return; 2297 } 2298 2299 Drawable selector = mSelector; 2300 Rect selectorRect = mSelectorRect; 2301 if (selector != null && (isFocused() || touchModeDrawsInPressedState()) 2302 && !selectorRect.isEmpty()) { 2303 2304 final View v = getChildAt(mSelectedPosition - mFirstPosition); 2305 2306 if (v != null) { 2307 if (v.hasFocusable()) return; 2308 v.setPressed(true); 2309 } 2310 setPressed(true); 2311 2312 final boolean longClickable = isLongClickable(); 2313 Drawable d = selector.getCurrent(); 2314 if (d != null && d instanceof TransitionDrawable) { 2315 if (longClickable) { 2316 ((TransitionDrawable) d).startTransition( 2317 ViewConfiguration.getLongPressTimeout()); 2318 } else { 2319 ((TransitionDrawable) d).resetTransition(); 2320 } 2321 } 2322 if (longClickable && !mDataChanged) { 2323 if (mPendingCheckForKeyLongPress == null) { 2324 mPendingCheckForKeyLongPress = new CheckForKeyLongPress(); 2325 } 2326 mPendingCheckForKeyLongPress.rememberWindowAttachCount(); 2327 postDelayed(mPendingCheckForKeyLongPress, ViewConfiguration.getLongPressTimeout()); 2328 } 2329 } 2330 } 2331 2332 public void setScrollIndicators(View up, View down) { 2333 mScrollUp = up; 2334 mScrollDown = down; 2335 } 2336 2337 void updateSelectorState() { 2338 if (mSelector != null) { 2339 if (shouldShowSelector()) { 2340 mSelector.setState(getDrawableState()); 2341 } else { 2342 mSelector.setState(StateSet.NOTHING); 2343 } 2344 } 2345 } 2346 2347 @Override 2348 protected void drawableStateChanged() { 2349 super.drawableStateChanged(); 2350 updateSelectorState(); 2351 } 2352 2353 @Override 2354 protected int[] onCreateDrawableState(int extraSpace) { 2355 // If the child view is enabled then do the default behavior. 2356 if (mIsChildViewEnabled) { 2357 // Common case 2358 return super.onCreateDrawableState(extraSpace); 2359 } 2360 2361 // The selector uses this View's drawable state. The selected child view 2362 // is disabled, so we need to remove the enabled state from the drawable 2363 // states. 2364 final int enabledState = ENABLED_STATE_SET[0]; 2365 2366 // If we don't have any extra space, it will return one of the static state arrays, 2367 // and clearing the enabled state on those arrays is a bad thing! If we specify 2368 // we need extra space, it will create+copy into a new array that safely mutable. 2369 int[] state = super.onCreateDrawableState(extraSpace + 1); 2370 int enabledPos = -1; 2371 for (int i = state.length - 1; i >= 0; i--) { 2372 if (state[i] == enabledState) { 2373 enabledPos = i; 2374 break; 2375 } 2376 } 2377 2378 // Remove the enabled state 2379 if (enabledPos >= 0) { 2380 System.arraycopy(state, enabledPos + 1, state, enabledPos, 2381 state.length - enabledPos - 1); 2382 } 2383 2384 return state; 2385 } 2386 2387 @Override 2388 public boolean verifyDrawable(Drawable dr) { 2389 return mSelector == dr || super.verifyDrawable(dr); 2390 } 2391 2392 @Override 2393 public void jumpDrawablesToCurrentState() { 2394 super.jumpDrawablesToCurrentState(); 2395 if (mSelector != null) mSelector.jumpToCurrentState(); 2396 } 2397 2398 @Override 2399 protected void onAttachedToWindow() { 2400 super.onAttachedToWindow(); 2401 2402 final ViewTreeObserver treeObserver = getViewTreeObserver(); 2403 treeObserver.addOnTouchModeChangeListener(this); 2404 if (mTextFilterEnabled && mPopup != null && !mGlobalLayoutListenerAddedFilter) { 2405 treeObserver.addOnGlobalLayoutListener(this); 2406 } 2407 2408 if (mAdapter != null && mDataSetObserver == null) { 2409 mDataSetObserver = new AdapterDataSetObserver(); 2410 mAdapter.registerDataSetObserver(mDataSetObserver); 2411 2412 // Data may have changed while we were detached. Refresh. 2413 mDataChanged = true; 2414 mOldItemCount = mItemCount; 2415 mItemCount = mAdapter.getCount(); 2416 } 2417 mIsAttached = true; 2418 } 2419 2420 @Override 2421 protected void onDetachedFromWindow() { 2422 super.onDetachedFromWindow(); 2423 2424 // Dismiss the popup in case onSaveInstanceState() was not invoked 2425 dismissPopup(); 2426 2427 // Detach any view left in the scrap heap 2428 mRecycler.clear(); 2429 2430 final ViewTreeObserver treeObserver = getViewTreeObserver(); 2431 treeObserver.removeOnTouchModeChangeListener(this); 2432 if (mTextFilterEnabled && mPopup != null) { 2433 treeObserver.removeOnGlobalLayoutListener(this); 2434 mGlobalLayoutListenerAddedFilter = false; 2435 } 2436 2437 if (mAdapter != null) { 2438 mAdapter.unregisterDataSetObserver(mDataSetObserver); 2439 mDataSetObserver = null; 2440 } 2441 2442 if (mScrollStrictSpan != null) { 2443 mScrollStrictSpan.finish(); 2444 mScrollStrictSpan = null; 2445 } 2446 2447 if (mFlingStrictSpan != null) { 2448 mFlingStrictSpan.finish(); 2449 mFlingStrictSpan = null; 2450 } 2451 2452 if (mFlingRunnable != null) { 2453 removeCallbacks(mFlingRunnable); 2454 } 2455 2456 if (mPositionScroller != null) { 2457 mPositionScroller.stop(); 2458 } 2459 2460 if (mClearScrollingCache != null) { 2461 removeCallbacks(mClearScrollingCache); 2462 } 2463 2464 if (mPerformClick != null) { 2465 removeCallbacks(mPerformClick); 2466 } 2467 2468 if (mTouchModeReset != null) { 2469 removeCallbacks(mTouchModeReset); 2470 mTouchModeReset = null; 2471 } 2472 mIsAttached = false; 2473 } 2474 2475 @Override 2476 public void onWindowFocusChanged(boolean hasWindowFocus) { 2477 super.onWindowFocusChanged(hasWindowFocus); 2478 2479 final int touchMode = isInTouchMode() ? TOUCH_MODE_ON : TOUCH_MODE_OFF; 2480 2481 if (!hasWindowFocus) { 2482 setChildrenDrawingCacheEnabled(false); 2483 if (mFlingRunnable != null) { 2484 removeCallbacks(mFlingRunnable); 2485 // let the fling runnable report it's new state which 2486 // should be idle 2487 mFlingRunnable.endFling(); 2488 if (mPositionScroller != null) { 2489 mPositionScroller.stop(); 2490 } 2491 if (mScrollY != 0) { 2492 mScrollY = 0; 2493 invalidateParentCaches(); 2494 finishGlows(); 2495 invalidate(); 2496 } 2497 } 2498 // Always hide the type filter 2499 dismissPopup(); 2500 2501 if (touchMode == TOUCH_MODE_OFF) { 2502 // Remember the last selected element 2503 mResurrectToPosition = mSelectedPosition; 2504 } 2505 } else { 2506 if (mFiltered && !mPopupHidden) { 2507 // Show the type filter only if a filter is in effect 2508 showPopup(); 2509 } 2510 2511 // If we changed touch mode since the last time we had focus 2512 if (touchMode != mLastTouchMode && mLastTouchMode != TOUCH_MODE_UNKNOWN) { 2513 // If we come back in trackball mode, we bring the selection back 2514 if (touchMode == TOUCH_MODE_OFF) { 2515 // This will trigger a layout 2516 resurrectSelection(); 2517 2518 // If we come back in touch mode, then we want to hide the selector 2519 } else { 2520 hideSelector(); 2521 mLayoutMode = LAYOUT_NORMAL; 2522 layoutChildren(); 2523 } 2524 } 2525 } 2526 2527 mLastTouchMode = touchMode; 2528 } 2529 2530 /** 2531 * Creates the ContextMenuInfo returned from {@link #getContextMenuInfo()}. This 2532 * methods knows the view, position and ID of the item that received the 2533 * long press. 2534 * 2535 * @param view The view that received the long press. 2536 * @param position The position of the item that received the long press. 2537 * @param id The ID of the item that received the long press. 2538 * @return The extra information that should be returned by 2539 * {@link #getContextMenuInfo()}. 2540 */ 2541 ContextMenuInfo createContextMenuInfo(View view, int position, long id) { 2542 return new AdapterContextMenuInfo(view, position, id); 2543 } 2544 2545 /** 2546 * A base class for Runnables that will check that their view is still attached to 2547 * the original window as when the Runnable was created. 2548 * 2549 */ 2550 private class WindowRunnnable { 2551 private int mOriginalAttachCount; 2552 2553 public void rememberWindowAttachCount() { 2554 mOriginalAttachCount = getWindowAttachCount(); 2555 } 2556 2557 public boolean sameWindow() { 2558 return hasWindowFocus() && getWindowAttachCount() == mOriginalAttachCount; 2559 } 2560 } 2561 2562 private class PerformClick extends WindowRunnnable implements Runnable { 2563 int mClickMotionPosition; 2564 2565 public void run() { 2566 // The data has changed since we posted this action in the event queue, 2567 // bail out before bad things happen 2568 if (mDataChanged) return; 2569 2570 final ListAdapter adapter = mAdapter; 2571 final int motionPosition = mClickMotionPosition; 2572 if (adapter != null && mItemCount > 0 && 2573 motionPosition != INVALID_POSITION && 2574 motionPosition < adapter.getCount() && sameWindow()) { 2575 final View view = getChildAt(motionPosition - mFirstPosition); 2576 // If there is no view, something bad happened (the view scrolled off the 2577 // screen, etc.) and we should cancel the click 2578 if (view != null) { 2579 performItemClick(view, motionPosition, adapter.getItemId(motionPosition)); 2580 } 2581 } 2582 } 2583 } 2584 2585 private class CheckForLongPress extends WindowRunnnable implements Runnable { 2586 public void run() { 2587 final int motionPosition = mMotionPosition; 2588 final View child = getChildAt(motionPosition - mFirstPosition); 2589 if (child != null) { 2590 final int longPressPosition = mMotionPosition; 2591 final long longPressId = mAdapter.getItemId(mMotionPosition); 2592 2593 boolean handled = false; 2594 if (sameWindow() && !mDataChanged) { 2595 handled = performLongPress(child, longPressPosition, longPressId); 2596 } 2597 if (handled) { 2598 mTouchMode = TOUCH_MODE_REST; 2599 setPressed(false); 2600 child.setPressed(false); 2601 } else { 2602 mTouchMode = TOUCH_MODE_DONE_WAITING; 2603 } 2604 } 2605 } 2606 } 2607 2608 private class CheckForKeyLongPress extends WindowRunnnable implements Runnable { 2609 public void run() { 2610 if (isPressed() && mSelectedPosition >= 0) { 2611 int index = mSelectedPosition - mFirstPosition; 2612 View v = getChildAt(index); 2613 2614 if (!mDataChanged) { 2615 boolean handled = false; 2616 if (sameWindow()) { 2617 handled = performLongPress(v, mSelectedPosition, mSelectedRowId); 2618 } 2619 if (handled) { 2620 setPressed(false); 2621 v.setPressed(false); 2622 } 2623 } else { 2624 setPressed(false); 2625 if (v != null) v.setPressed(false); 2626 } 2627 } 2628 } 2629 } 2630 2631 boolean performLongPress(final View child, 2632 final int longPressPosition, final long longPressId) { 2633 // CHOICE_MODE_MULTIPLE_MODAL takes over long press. 2634 if (mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL) { 2635 if (mChoiceActionMode == null && 2636 (mChoiceActionMode = startActionMode(mMultiChoiceModeCallback)) != null) { 2637 setItemChecked(longPressPosition, true); 2638 performHapticFeedback(HapticFeedbackConstants.LONG_PRESS); 2639 } 2640 return true; 2641 } 2642 2643 boolean handled = false; 2644 if (mOnItemLongClickListener != null) { 2645 handled = mOnItemLongClickListener.onItemLongClick(AbsListView.this, child, 2646 longPressPosition, longPressId); 2647 } 2648 if (!handled) { 2649 mContextMenuInfo = createContextMenuInfo(child, longPressPosition, longPressId); 2650 handled = super.showContextMenuForChild(AbsListView.this); 2651 } 2652 if (handled) { 2653 performHapticFeedback(HapticFeedbackConstants.LONG_PRESS); 2654 } 2655 return handled; 2656 } 2657 2658 @Override 2659 protected ContextMenuInfo getContextMenuInfo() { 2660 return mContextMenuInfo; 2661 } 2662 2663 /** @hide */ 2664 @Override 2665 public boolean showContextMenu(float x, float y, int metaState) { 2666 final int position = pointToPosition((int)x, (int)y); 2667 if (position != INVALID_POSITION) { 2668 final long id = mAdapter.getItemId(position); 2669 View child = getChildAt(position - mFirstPosition); 2670 if (child != null) { 2671 mContextMenuInfo = createContextMenuInfo(child, position, id); 2672 return super.showContextMenuForChild(AbsListView.this); 2673 } 2674 } 2675 return super.showContextMenu(x, y, metaState); 2676 } 2677 2678 @Override 2679 public boolean showContextMenuForChild(View originalView) { 2680 final int longPressPosition = getPositionForView(originalView); 2681 if (longPressPosition >= 0) { 2682 final long longPressId = mAdapter.getItemId(longPressPosition); 2683 boolean handled = false; 2684 2685 if (mOnItemLongClickListener != null) { 2686 handled = mOnItemLongClickListener.onItemLongClick(AbsListView.this, originalView, 2687 longPressPosition, longPressId); 2688 } 2689 if (!handled) { 2690 mContextMenuInfo = createContextMenuInfo( 2691 getChildAt(longPressPosition - mFirstPosition), 2692 longPressPosition, longPressId); 2693 handled = super.showContextMenuForChild(originalView); 2694 } 2695 2696 return handled; 2697 } 2698 return false; 2699 } 2700 2701 @Override 2702 public boolean onKeyDown(int keyCode, KeyEvent event) { 2703 return false; 2704 } 2705 2706 @Override 2707 public boolean onKeyUp(int keyCode, KeyEvent event) { 2708 switch (keyCode) { 2709 case KeyEvent.KEYCODE_DPAD_CENTER: 2710 case KeyEvent.KEYCODE_ENTER: 2711 if (!isEnabled()) { 2712 return true; 2713 } 2714 if (isClickable() && isPressed() && 2715 mSelectedPosition >= 0 && mAdapter != null && 2716 mSelectedPosition < mAdapter.getCount()) { 2717 2718 final View view = getChildAt(mSelectedPosition - mFirstPosition); 2719 if (view != null) { 2720 performItemClick(view, mSelectedPosition, mSelectedRowId); 2721 view.setPressed(false); 2722 } 2723 setPressed(false); 2724 return true; 2725 } 2726 break; 2727 } 2728 return super.onKeyUp(keyCode, event); 2729 } 2730 2731 @Override 2732 protected void dispatchSetPressed(boolean pressed) { 2733 // Don't dispatch setPressed to our children. We call setPressed on ourselves to 2734 // get the selector in the right state, but we don't want to press each child. 2735 } 2736 2737 /** 2738 * Maps a point to a position in the list. 2739 * 2740 * @param x X in local coordinate 2741 * @param y Y in local coordinate 2742 * @return The position of the item which contains the specified point, or 2743 * {@link #INVALID_POSITION} if the point does not intersect an item. 2744 */ 2745 public int pointToPosition(int x, int y) { 2746 Rect frame = mTouchFrame; 2747 if (frame == null) { 2748 mTouchFrame = new Rect(); 2749 frame = mTouchFrame; 2750 } 2751 2752 final int count = getChildCount(); 2753 for (int i = count - 1; i >= 0; i--) { 2754 final View child = getChildAt(i); 2755 if (child.getVisibility() == View.VISIBLE) { 2756 child.getHitRect(frame); 2757 if (frame.contains(x, y)) { 2758 return mFirstPosition + i; 2759 } 2760 } 2761 } 2762 return INVALID_POSITION; 2763 } 2764 2765 2766 /** 2767 * Maps a point to a the rowId of the item which intersects that point. 2768 * 2769 * @param x X in local coordinate 2770 * @param y Y in local coordinate 2771 * @return The rowId of the item which contains the specified point, or {@link #INVALID_ROW_ID} 2772 * if the point does not intersect an item. 2773 */ 2774 public long pointToRowId(int x, int y) { 2775 int position = pointToPosition(x, y); 2776 if (position >= 0) { 2777 return mAdapter.getItemId(position); 2778 } 2779 return INVALID_ROW_ID; 2780 } 2781 2782 final class CheckForTap implements Runnable { 2783 public void run() { 2784 if (mTouchMode == TOUCH_MODE_DOWN) { 2785 mTouchMode = TOUCH_MODE_TAP; 2786 final View child = getChildAt(mMotionPosition - mFirstPosition); 2787 if (child != null && !child.hasFocusable()) { 2788 mLayoutMode = LAYOUT_NORMAL; 2789 2790 if (!mDataChanged) { 2791 child.setPressed(true); 2792 setPressed(true); 2793 layoutChildren(); 2794 positionSelector(mMotionPosition, child); 2795 refreshDrawableState(); 2796 2797 final int longPressTimeout = ViewConfiguration.getLongPressTimeout(); 2798 final boolean longClickable = isLongClickable(); 2799 2800 if (mSelector != null) { 2801 Drawable d = mSelector.getCurrent(); 2802 if (d != null && d instanceof TransitionDrawable) { 2803 if (longClickable) { 2804 ((TransitionDrawable) d).startTransition(longPressTimeout); 2805 } else { 2806 ((TransitionDrawable) d).resetTransition(); 2807 } 2808 } 2809 } 2810 2811 if (longClickable) { 2812 if (mPendingCheckForLongPress == null) { 2813 mPendingCheckForLongPress = new CheckForLongPress(); 2814 } 2815 mPendingCheckForLongPress.rememberWindowAttachCount(); 2816 postDelayed(mPendingCheckForLongPress, longPressTimeout); 2817 } else { 2818 mTouchMode = TOUCH_MODE_DONE_WAITING; 2819 } 2820 } else { 2821 mTouchMode = TOUCH_MODE_DONE_WAITING; 2822 } 2823 } 2824 } 2825 } 2826 } 2827 2828 private boolean startScrollIfNeeded(int y) { 2829 // Check if we have moved far enough that it looks more like a 2830 // scroll than a tap 2831 final int deltaY = y - mMotionY; 2832 final int distance = Math.abs(deltaY); 2833 final boolean overscroll = mScrollY != 0; 2834 if (overscroll || distance > mTouchSlop) { 2835 createScrollingCache(); 2836 if (overscroll) { 2837 mTouchMode = TOUCH_MODE_OVERSCROLL; 2838 mMotionCorrection = 0; 2839 } else { 2840 mTouchMode = TOUCH_MODE_SCROLL; 2841 mMotionCorrection = deltaY > 0 ? mTouchSlop : -mTouchSlop; 2842 } 2843 final Handler handler = getHandler(); 2844 // Handler should not be null unless the AbsListView is not attached to a 2845 // window, which would make it very hard to scroll it... but the monkeys 2846 // say it's possible. 2847 if (handler != null) { 2848 handler.removeCallbacks(mPendingCheckForLongPress); 2849 } 2850 setPressed(false); 2851 View motionView = getChildAt(mMotionPosition - mFirstPosition); 2852 if (motionView != null) { 2853 motionView.setPressed(false); 2854 } 2855 reportScrollStateChange(OnScrollListener.SCROLL_STATE_TOUCH_SCROLL); 2856 // Time to start stealing events! Once we've stolen them, don't let anyone 2857 // steal from us 2858 final ViewParent parent = getParent(); 2859 if (parent != null) { 2860 parent.requestDisallowInterceptTouchEvent(true); 2861 } 2862 scrollIfNeeded(y); 2863 return true; 2864 } 2865 2866 return false; 2867 } 2868 2869 private void scrollIfNeeded(int y) { 2870 final int rawDeltaY = y - mMotionY; 2871 final int deltaY = rawDeltaY - mMotionCorrection; 2872 int incrementalDeltaY = mLastY != Integer.MIN_VALUE ? y - mLastY : deltaY; 2873 2874 if (mTouchMode == TOUCH_MODE_SCROLL) { 2875 if (PROFILE_SCROLLING) { 2876 if (!mScrollProfilingStarted) { 2877 Debug.startMethodTracing("AbsListViewScroll"); 2878 mScrollProfilingStarted = true; 2879 } 2880 } 2881 2882 if (mScrollStrictSpan == null) { 2883 // If it's non-null, we're already in a scroll. 2884 mScrollStrictSpan = StrictMode.enterCriticalSpan("AbsListView-scroll"); 2885 } 2886 2887 if (y != mLastY) { 2888 // We may be here after stopping a fling and continuing to scroll. 2889 // If so, we haven't disallowed intercepting touch events yet. 2890 // Make sure that we do so in case we're in a parent that can intercept. 2891 if ((mGroupFlags & FLAG_DISALLOW_INTERCEPT) == 0 && 2892 Math.abs(rawDeltaY) > mTouchSlop) { 2893 final ViewParent parent = getParent(); 2894 if (parent != null) { 2895 parent.requestDisallowInterceptTouchEvent(true); 2896 } 2897 } 2898 2899 final int motionIndex; 2900 if (mMotionPosition >= 0) { 2901 motionIndex = mMotionPosition - mFirstPosition; 2902 } else { 2903 // If we don't have a motion position that we can reliably track, 2904 // pick something in the middle to make a best guess at things below. 2905 motionIndex = getChildCount() / 2; 2906 } 2907 2908 int motionViewPrevTop = 0; 2909 View motionView = this.getChildAt(motionIndex); 2910 if (motionView != null) { 2911 motionViewPrevTop = motionView.getTop(); 2912 } 2913 2914 // No need to do all this work if we're not going to move anyway 2915 boolean atEdge = false; 2916 if (incrementalDeltaY != 0) { 2917 atEdge = trackMotionScroll(deltaY, incrementalDeltaY); 2918 } 2919 2920 // Check to see if we have bumped into the scroll limit 2921 motionView = this.getChildAt(motionIndex); 2922 if (motionView != null) { 2923 // Check if the top of the motion view is where it is 2924 // supposed to be 2925 final int motionViewRealTop = motionView.getTop(); 2926 if (atEdge) { 2927 // Apply overscroll 2928 2929 int overscroll = -incrementalDeltaY - 2930 (motionViewRealTop - motionViewPrevTop); 2931 overScrollBy(0, overscroll, 0, mScrollY, 0, 0, 2932 0, mOverscrollDistance, true); 2933 if (Math.abs(mOverscrollDistance) == Math.abs(mScrollY)) { 2934 // Don't allow overfling if we're at the edge. 2935 if (mVelocityTracker != null) { 2936 mVelocityTracker.clear(); 2937 } 2938 } 2939 2940 final int overscrollMode = getOverScrollMode(); 2941 if (overscrollMode == OVER_SCROLL_ALWAYS || 2942 (overscrollMode == OVER_SCROLL_IF_CONTENT_SCROLLS && 2943 !contentFits())) { 2944 mDirection = 0; // Reset when entering overscroll. 2945 mTouchMode = TOUCH_MODE_OVERSCROLL; 2946 if (rawDeltaY > 0) { 2947 if (!mEdgeGlowTop.isIdle()) { 2948 invalidate(mEdgeGlowTop.getBounds()); 2949 } else { 2950 invalidate(); 2951 } 2952 2953 mEdgeGlowTop.onPull((float) overscroll / getHeight()); 2954 if (!mEdgeGlowBottom.isFinished()) { 2955 mEdgeGlowBottom.onRelease(); 2956 } 2957 } else if (rawDeltaY < 0) { 2958 if (!mEdgeGlowBottom.isIdle()) { 2959 invalidate(mEdgeGlowBottom.getBounds()); 2960 } else { 2961 invalidate(); 2962 } 2963 2964 mEdgeGlowBottom.onPull((float) overscroll / getHeight()); 2965 if (!mEdgeGlowTop.isFinished()) { 2966 mEdgeGlowTop.onRelease(); 2967 } 2968 } 2969 } 2970 } 2971 mMotionY = y; 2972 } 2973 mLastY = y; 2974 } 2975 } else if (mTouchMode == TOUCH_MODE_OVERSCROLL) { 2976 if (y != mLastY) { 2977 final int oldScroll = mScrollY; 2978 final int newScroll = oldScroll - incrementalDeltaY; 2979 int newDirection = y > mLastY ? 1 : -1; 2980 2981 if (mDirection == 0) { 2982 mDirection = newDirection; 2983 } 2984 2985 int overScrollDistance = -incrementalDeltaY; 2986 if ((newScroll < 0 && oldScroll >= 0) || (newScroll > 0 && oldScroll <= 0)) { 2987 overScrollDistance = -oldScroll; 2988 incrementalDeltaY += overScrollDistance; 2989 } else { 2990 incrementalDeltaY = 0; 2991 } 2992 2993 if (overScrollDistance != 0) { 2994 overScrollBy(0, overScrollDistance, 0, mScrollY, 0, 0, 2995 0, mOverscrollDistance, true); 2996 final int overscrollMode = getOverScrollMode(); 2997 if (overscrollMode == OVER_SCROLL_ALWAYS || 2998 (overscrollMode == OVER_SCROLL_IF_CONTENT_SCROLLS && 2999 !contentFits())) { 3000 if (rawDeltaY > 0) { 3001 mEdgeGlowTop.onPull((float) overScrollDistance / getHeight()); 3002 if (!mEdgeGlowBottom.isFinished()) { 3003 mEdgeGlowBottom.onRelease(); 3004 } 3005 invalidate(mEdgeGlowTop.getBounds()); 3006 } else if (rawDeltaY < 0) { 3007 mEdgeGlowBottom.onPull((float) overScrollDistance / getHeight()); 3008 if (!mEdgeGlowTop.isFinished()) { 3009 mEdgeGlowTop.onRelease(); 3010 } 3011 invalidate(mEdgeGlowBottom.getBounds()); 3012 } 3013 } 3014 } 3015 3016 if (incrementalDeltaY != 0) { 3017 // Coming back to 'real' list scrolling 3018 if (mScrollY != 0) { 3019 mScrollY = 0; 3020 invalidateParentIfNeeded(); 3021 } 3022 3023 trackMotionScroll(incrementalDeltaY, incrementalDeltaY); 3024 3025 mTouchMode = TOUCH_MODE_SCROLL; 3026 3027 // We did not scroll the full amount. Treat this essentially like the 3028 // start of a new touch scroll 3029 final int motionPosition = findClosestMotionRow(y); 3030 3031 mMotionCorrection = 0; 3032 View motionView = getChildAt(motionPosition - mFirstPosition); 3033 mMotionViewOriginalTop = motionView != null ? motionView.getTop() : 0; 3034 mMotionY = y; 3035 mMotionPosition = motionPosition; 3036 } 3037 mLastY = y; 3038 mDirection = newDirection; 3039 } 3040 } 3041 } 3042 3043 public void onTouchModeChanged(boolean isInTouchMode) { 3044 if (isInTouchMode) { 3045 // Get rid of the selection when we enter touch mode 3046 hideSelector(); 3047 // Layout, but only if we already have done so previously. 3048 // (Otherwise may clobber a LAYOUT_SYNC layout that was requested to restore 3049 // state.) 3050 if (getHeight() > 0 && getChildCount() > 0) { 3051 // We do not lose focus initiating a touch (since AbsListView is focusable in 3052 // touch mode). Force an initial layout to get rid of the selection. 3053 layoutChildren(); 3054 } 3055 updateSelectorState(); 3056 } else { 3057 int touchMode = mTouchMode; 3058 if (touchMode == TOUCH_MODE_OVERSCROLL || touchMode == TOUCH_MODE_OVERFLING) { 3059 if (mFlingRunnable != null) { 3060 mFlingRunnable.endFling(); 3061 } 3062 if (mPositionScroller != null) { 3063 mPositionScroller.stop(); 3064 } 3065 3066 if (mScrollY != 0) { 3067 mScrollY = 0; 3068 invalidateParentCaches(); 3069 finishGlows(); 3070 invalidate(); 3071 } 3072 } 3073 } 3074 } 3075 3076 @Override 3077 public boolean onTouchEvent(MotionEvent ev) { 3078 if (!isEnabled()) { 3079 // A disabled view that is clickable still consumes the touch 3080 // events, it just doesn't respond to them. 3081 return isClickable() || isLongClickable(); 3082 } 3083 3084 if (mFastScroller != null) { 3085 boolean intercepted = mFastScroller.onTouchEvent(ev); 3086 if (intercepted) { 3087 return true; 3088 } 3089 } 3090 3091 final int action = ev.getAction(); 3092 3093 View v; 3094 3095 initVelocityTrackerIfNotExists(); 3096 mVelocityTracker.addMovement(ev); 3097 3098 switch (action & MotionEvent.ACTION_MASK) { 3099 case MotionEvent.ACTION_DOWN: { 3100 switch (mTouchMode) { 3101 case TOUCH_MODE_OVERFLING: { 3102 mFlingRunnable.endFling(); 3103 if (mPositionScroller != null) { 3104 mPositionScroller.stop(); 3105 } 3106 mTouchMode = TOUCH_MODE_OVERSCROLL; 3107 mMotionX = (int) ev.getX(); 3108 mMotionY = mLastY = (int) ev.getY(); 3109 mMotionCorrection = 0; 3110 mActivePointerId = ev.getPointerId(0); 3111 mDirection = 0; 3112 break; 3113 } 3114 3115 default: { 3116 mActivePointerId = ev.getPointerId(0); 3117 final int x = (int) ev.getX(); 3118 final int y = (int) ev.getY(); 3119 int motionPosition = pointToPosition(x, y); 3120 if (!mDataChanged) { 3121 if ((mTouchMode != TOUCH_MODE_FLING) && (motionPosition >= 0) 3122 && (getAdapter().isEnabled(motionPosition))) { 3123 // User clicked on an actual view (and was not stopping a fling). 3124 // It might be a click or a scroll. Assume it is a click until 3125 // proven otherwise 3126 mTouchMode = TOUCH_MODE_DOWN; 3127 // FIXME Debounce 3128 if (mPendingCheckForTap == null) { 3129 mPendingCheckForTap = new CheckForTap(); 3130 } 3131 postDelayed(mPendingCheckForTap, ViewConfiguration.getTapTimeout()); 3132 } else { 3133 if (mTouchMode == TOUCH_MODE_FLING) { 3134 // Stopped a fling. It is a scroll. 3135 createScrollingCache(); 3136 mTouchMode = TOUCH_MODE_SCROLL; 3137 mMotionCorrection = 0; 3138 motionPosition = findMotionRow(y); 3139 mFlingRunnable.flywheelTouch(); 3140 } 3141 } 3142 } 3143 3144 if (motionPosition >= 0) { 3145 // Remember where the motion event started 3146 v = getChildAt(motionPosition - mFirstPosition); 3147 mMotionViewOriginalTop = v.getTop(); 3148 } 3149 mMotionX = x; 3150 mMotionY = y; 3151 mMotionPosition = motionPosition; 3152 mLastY = Integer.MIN_VALUE; 3153 break; 3154 } 3155 } 3156 3157 if (performButtonActionOnTouchDown(ev)) { 3158 if (mTouchMode == TOUCH_MODE_DOWN) { 3159 removeCallbacks(mPendingCheckForTap); 3160 } 3161 } 3162 break; 3163 } 3164 3165 case MotionEvent.ACTION_MOVE: { 3166 int pointerIndex = ev.findPointerIndex(mActivePointerId); 3167 if (pointerIndex == -1) { 3168 pointerIndex = 0; 3169 mActivePointerId = ev.getPointerId(pointerIndex); 3170 } 3171 final int y = (int) ev.getY(pointerIndex); 3172 switch (mTouchMode) { 3173 case TOUCH_MODE_DOWN: 3174 case TOUCH_MODE_TAP: 3175 case TOUCH_MODE_DONE_WAITING: 3176 // Check if we have moved far enough that it looks more like a 3177 // scroll than a tap 3178 startScrollIfNeeded(y); 3179 break; 3180 case TOUCH_MODE_SCROLL: 3181 case TOUCH_MODE_OVERSCROLL: 3182 scrollIfNeeded(y); 3183 break; 3184 } 3185 break; 3186 } 3187 3188 case MotionEvent.ACTION_UP: { 3189 switch (mTouchMode) { 3190 case TOUCH_MODE_DOWN: 3191 case TOUCH_MODE_TAP: 3192 case TOUCH_MODE_DONE_WAITING: 3193 final int motionPosition = mMotionPosition; 3194 final View child = getChildAt(motionPosition - mFirstPosition); 3195 3196 final float x = ev.getX(); 3197 final boolean inList = x > mListPadding.left && x < getWidth() - mListPadding.right; 3198 3199 if (child != null && !child.hasFocusable() && inList) { 3200 if (mTouchMode != TOUCH_MODE_DOWN) { 3201 child.setPressed(false); 3202 } 3203 3204 if (mPerformClick == null) { 3205 mPerformClick = new PerformClick(); 3206 } 3207 3208 final AbsListView.PerformClick performClick = mPerformClick; 3209 performClick.mClickMotionPosition = motionPosition; 3210 performClick.rememberWindowAttachCount(); 3211 3212 mResurrectToPosition = motionPosition; 3213 3214 if (mTouchMode == TOUCH_MODE_DOWN || mTouchMode == TOUCH_MODE_TAP) { 3215 final Handler handler = getHandler(); 3216 if (handler != null) { 3217 handler.removeCallbacks(mTouchMode == TOUCH_MODE_DOWN ? 3218 mPendingCheckForTap : mPendingCheckForLongPress); 3219 } 3220 mLayoutMode = LAYOUT_NORMAL; 3221 if (!mDataChanged && mAdapter.isEnabled(motionPosition)) { 3222 mTouchMode = TOUCH_MODE_TAP; 3223 setSelectedPositionInt(mMotionPosition); 3224 layoutChildren(); 3225 child.setPressed(true); 3226 positionSelector(mMotionPosition, child); 3227 setPressed(true); 3228 if (mSelector != null) { 3229 Drawable d = mSelector.getCurrent(); 3230 if (d != null && d instanceof TransitionDrawable) { 3231 ((TransitionDrawable) d).resetTransition(); 3232 } 3233 } 3234 if (mTouchModeReset != null) { 3235 removeCallbacks(mTouchModeReset); 3236 } 3237 mTouchModeReset = new Runnable() { 3238 @Override 3239 public void run() { 3240 mTouchMode = TOUCH_MODE_REST; 3241 child.setPressed(false); 3242 setPressed(false); 3243 if (!mDataChanged) { 3244 performClick.run(); 3245 } 3246 } 3247 }; 3248 postDelayed(mTouchModeReset, 3249 ViewConfiguration.getPressedStateDuration()); 3250 } else { 3251 mTouchMode = TOUCH_MODE_REST; 3252 updateSelectorState(); 3253 } 3254 return true; 3255 } else if (!mDataChanged && mAdapter.isEnabled(motionPosition)) { 3256 performClick.run(); 3257 } 3258 } 3259 mTouchMode = TOUCH_MODE_REST; 3260 updateSelectorState(); 3261 break; 3262 case TOUCH_MODE_SCROLL: 3263 final int childCount = getChildCount(); 3264 if (childCount > 0) { 3265 final int firstChildTop = getChildAt(0).getTop(); 3266 final int lastChildBottom = getChildAt(childCount - 1).getBottom(); 3267 final int contentTop = mListPadding.top; 3268 final int contentBottom = getHeight() - mListPadding.bottom; 3269 if (mFirstPosition == 0 && firstChildTop >= contentTop && 3270 mFirstPosition + childCount < mItemCount && 3271 lastChildBottom <= getHeight() - contentBottom) { 3272 mTouchMode = TOUCH_MODE_REST; 3273 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 3274 } else { 3275 final VelocityTracker velocityTracker = mVelocityTracker; 3276 velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity); 3277 3278 final int initialVelocity = (int) 3279 (velocityTracker.getYVelocity(mActivePointerId) * mVelocityScale); 3280 // Fling if we have enough velocity and we aren't at a boundary. 3281 // Since we can potentially overfling more than we can overscroll, don't 3282 // allow the weird behavior where you can scroll to a boundary then 3283 // fling further. 3284 if (Math.abs(initialVelocity) > mMinimumVelocity && 3285 !((mFirstPosition == 0 && 3286 firstChildTop == contentTop - mOverscrollDistance) || 3287 (mFirstPosition + childCount == mItemCount && 3288 lastChildBottom == contentBottom + mOverscrollDistance))) { 3289 if (mFlingRunnable == null) { 3290 mFlingRunnable = new FlingRunnable(); 3291 } 3292 reportScrollStateChange(OnScrollListener.SCROLL_STATE_FLING); 3293 3294 mFlingRunnable.start(-initialVelocity); 3295 } else { 3296 mTouchMode = TOUCH_MODE_REST; 3297 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 3298 if (mFlingRunnable != null) { 3299 mFlingRunnable.endFling(); 3300 } 3301 if (mPositionScroller != null) { 3302 mPositionScroller.stop(); 3303 } 3304 } 3305 } 3306 } else { 3307 mTouchMode = TOUCH_MODE_REST; 3308 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 3309 } 3310 break; 3311 3312 case TOUCH_MODE_OVERSCROLL: 3313 if (mFlingRunnable == null) { 3314 mFlingRunnable = new FlingRunnable(); 3315 } 3316 final VelocityTracker velocityTracker = mVelocityTracker; 3317 velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity); 3318 final int initialVelocity = (int) velocityTracker.getYVelocity(mActivePointerId); 3319 3320 reportScrollStateChange(OnScrollListener.SCROLL_STATE_FLING); 3321 if (Math.abs(initialVelocity) > mMinimumVelocity) { 3322 mFlingRunnable.startOverfling(-initialVelocity); 3323 } else { 3324 mFlingRunnable.startSpringback(); 3325 } 3326 3327 break; 3328 } 3329 3330 setPressed(false); 3331 3332 if (mEdgeGlowTop != null) { 3333 mEdgeGlowTop.onRelease(); 3334 mEdgeGlowBottom.onRelease(); 3335 } 3336 3337 // Need to redraw since we probably aren't drawing the selector anymore 3338 invalidate(); 3339 3340 final Handler handler = getHandler(); 3341 if (handler != null) { 3342 handler.removeCallbacks(mPendingCheckForLongPress); 3343 } 3344 3345 recycleVelocityTracker(); 3346 3347 mActivePointerId = INVALID_POINTER; 3348 3349 if (PROFILE_SCROLLING) { 3350 if (mScrollProfilingStarted) { 3351 Debug.stopMethodTracing(); 3352 mScrollProfilingStarted = false; 3353 } 3354 } 3355 3356 if (mScrollStrictSpan != null) { 3357 mScrollStrictSpan.finish(); 3358 mScrollStrictSpan = null; 3359 } 3360 break; 3361 } 3362 3363 case MotionEvent.ACTION_CANCEL: { 3364 switch (mTouchMode) { 3365 case TOUCH_MODE_OVERSCROLL: 3366 if (mFlingRunnable == null) { 3367 mFlingRunnable = new FlingRunnable(); 3368 } 3369 mFlingRunnable.startSpringback(); 3370 break; 3371 3372 case TOUCH_MODE_OVERFLING: 3373 // Do nothing - let it play out. 3374 break; 3375 3376 default: 3377 mTouchMode = TOUCH_MODE_REST; 3378 setPressed(false); 3379 View motionView = this.getChildAt(mMotionPosition - mFirstPosition); 3380 if (motionView != null) { 3381 motionView.setPressed(false); 3382 } 3383 clearScrollingCache(); 3384 3385 final Handler handler = getHandler(); 3386 if (handler != null) { 3387 handler.removeCallbacks(mPendingCheckForLongPress); 3388 } 3389 3390 recycleVelocityTracker(); 3391 } 3392 3393 if (mEdgeGlowTop != null) { 3394 mEdgeGlowTop.onRelease(); 3395 mEdgeGlowBottom.onRelease(); 3396 } 3397 mActivePointerId = INVALID_POINTER; 3398 break; 3399 } 3400 3401 case MotionEvent.ACTION_POINTER_UP: { 3402 onSecondaryPointerUp(ev); 3403 final int x = mMotionX; 3404 final int y = mMotionY; 3405 final int motionPosition = pointToPosition(x, y); 3406 if (motionPosition >= 0) { 3407 // Remember where the motion event started 3408 v = getChildAt(motionPosition - mFirstPosition); 3409 mMotionViewOriginalTop = v.getTop(); 3410 mMotionPosition = motionPosition; 3411 } 3412 mLastY = y; 3413 break; 3414 } 3415 3416 case MotionEvent.ACTION_POINTER_DOWN: { 3417 // New pointers take over dragging duties 3418 final int index = ev.getActionIndex(); 3419 final int id = ev.getPointerId(index); 3420 final int x = (int) ev.getX(index); 3421 final int y = (int) ev.getY(index); 3422 mMotionCorrection = 0; 3423 mActivePointerId = id; 3424 mMotionX = x; 3425 mMotionY = y; 3426 final int motionPosition = pointToPosition(x, y); 3427 if (motionPosition >= 0) { 3428 // Remember where the motion event started 3429 v = getChildAt(motionPosition - mFirstPosition); 3430 mMotionViewOriginalTop = v.getTop(); 3431 mMotionPosition = motionPosition; 3432 } 3433 mLastY = y; 3434 break; 3435 } 3436 } 3437 3438 return true; 3439 } 3440 3441 @Override 3442 protected void onOverScrolled(int scrollX, int scrollY, boolean clampedX, boolean clampedY) { 3443 if (mScrollY != scrollY) { 3444 onScrollChanged(mScrollX, scrollY, mScrollX, mScrollY); 3445 mScrollY = scrollY; 3446 invalidateParentIfNeeded(); 3447 3448 awakenScrollBars(); 3449 } 3450 } 3451 3452 @Override 3453 public boolean onGenericMotionEvent(MotionEvent event) { 3454 if ((event.getSource() & InputDevice.SOURCE_CLASS_POINTER) != 0) { 3455 switch (event.getAction()) { 3456 case MotionEvent.ACTION_SCROLL: { 3457 if (mTouchMode == TOUCH_MODE_REST) { 3458 final float vscroll = event.getAxisValue(MotionEvent.AXIS_VSCROLL); 3459 if (vscroll != 0) { 3460 final int delta = (int) (vscroll * getVerticalScrollFactor()); 3461 if (!trackMotionScroll(delta, delta)) { 3462 return true; 3463 } 3464 } 3465 } 3466 } 3467 } 3468 } 3469 return super.onGenericMotionEvent(event); 3470 } 3471 3472 @Override 3473 public void draw(Canvas canvas) { 3474 super.draw(canvas); 3475 if (mEdgeGlowTop != null) { 3476 final int scrollY = mScrollY; 3477 if (!mEdgeGlowTop.isFinished()) { 3478 final int restoreCount = canvas.save(); 3479 final int leftPadding = mListPadding.left + mGlowPaddingLeft; 3480 final int rightPadding = mListPadding.right + mGlowPaddingRight; 3481 final int width = getWidth() - leftPadding - rightPadding; 3482 3483 int edgeY = Math.min(0, scrollY + mFirstPositionDistanceGuess); 3484 canvas.translate(leftPadding, edgeY); 3485 mEdgeGlowTop.setSize(width, getHeight()); 3486 if (mEdgeGlowTop.draw(canvas)) { 3487 mEdgeGlowTop.setPosition(leftPadding, edgeY); 3488 invalidate(mEdgeGlowTop.getBounds()); 3489 } 3490 canvas.restoreToCount(restoreCount); 3491 } 3492 if (!mEdgeGlowBottom.isFinished()) { 3493 final int restoreCount = canvas.save(); 3494 final int leftPadding = mListPadding.left + mGlowPaddingLeft; 3495 final int rightPadding = mListPadding.right + mGlowPaddingRight; 3496 final int width = getWidth() - leftPadding - rightPadding; 3497 final int height = getHeight(); 3498 3499 int edgeX = -width + leftPadding; 3500 int edgeY = Math.max(height, scrollY + mLastPositionDistanceGuess); 3501 canvas.translate(edgeX, edgeY); 3502 canvas.rotate(180, width, 0); 3503 mEdgeGlowBottom.setSize(width, height); 3504 if (mEdgeGlowBottom.draw(canvas)) { 3505 // Account for the rotation 3506 mEdgeGlowBottom.setPosition(edgeX + width, edgeY - mEdgeGlowBottom.getHeight()); 3507 invalidate(mEdgeGlowBottom.getBounds()); 3508 } 3509 canvas.restoreToCount(restoreCount); 3510 } 3511 } 3512 if (mFastScroller != null) { 3513 final int scrollY = mScrollY; 3514 if (scrollY != 0) { 3515 // Pin to the top/bottom during overscroll 3516 int restoreCount = canvas.save(); 3517 canvas.translate(0, (float) scrollY); 3518 mFastScroller.draw(canvas); 3519 canvas.restoreToCount(restoreCount); 3520 } else { 3521 mFastScroller.draw(canvas); 3522 } 3523 } 3524 } 3525 3526 /** 3527 * @hide 3528 */ 3529 public void setOverScrollEffectPadding(int leftPadding, int rightPadding) { 3530 mGlowPaddingLeft = leftPadding; 3531 mGlowPaddingRight = rightPadding; 3532 } 3533 3534 private void initOrResetVelocityTracker() { 3535 if (mVelocityTracker == null) { 3536 mVelocityTracker = VelocityTracker.obtain(); 3537 } else { 3538 mVelocityTracker.clear(); 3539 } 3540 } 3541 3542 private void initVelocityTrackerIfNotExists() { 3543 if (mVelocityTracker == null) { 3544 mVelocityTracker = VelocityTracker.obtain(); 3545 } 3546 } 3547 3548 private void recycleVelocityTracker() { 3549 if (mVelocityTracker != null) { 3550 mVelocityTracker.recycle(); 3551 mVelocityTracker = null; 3552 } 3553 } 3554 3555 @Override 3556 public void requestDisallowInterceptTouchEvent(boolean disallowIntercept) { 3557 if (disallowIntercept) { 3558 recycleVelocityTracker(); 3559 } 3560 super.requestDisallowInterceptTouchEvent(disallowIntercept); 3561 } 3562 3563 @Override 3564 public boolean onInterceptTouchEvent(MotionEvent ev) { 3565 int action = ev.getAction(); 3566 View v; 3567 3568 if (mFastScroller != null) { 3569 boolean intercepted = mFastScroller.onInterceptTouchEvent(ev); 3570 if (intercepted) { 3571 return true; 3572 } 3573 } 3574 3575 switch (action & MotionEvent.ACTION_MASK) { 3576 case MotionEvent.ACTION_DOWN: { 3577 int touchMode = mTouchMode; 3578 if (touchMode == TOUCH_MODE_OVERFLING || touchMode == TOUCH_MODE_OVERSCROLL) { 3579 mMotionCorrection = 0; 3580 return true; 3581 } 3582 3583 final int x = (int) ev.getX(); 3584 final int y = (int) ev.getY(); 3585 mActivePointerId = ev.getPointerId(0); 3586 3587 int motionPosition = findMotionRow(y); 3588 if (touchMode != TOUCH_MODE_FLING && motionPosition >= 0) { 3589 // User clicked on an actual view (and was not stopping a fling). 3590 // Remember where the motion event started 3591 v = getChildAt(motionPosition - mFirstPosition); 3592 mMotionViewOriginalTop = v.getTop(); 3593 mMotionX = x; 3594 mMotionY = y; 3595 mMotionPosition = motionPosition; 3596 mTouchMode = TOUCH_MODE_DOWN; 3597 clearScrollingCache(); 3598 } 3599 mLastY = Integer.MIN_VALUE; 3600 initOrResetVelocityTracker(); 3601 mVelocityTracker.addMovement(ev); 3602 if (touchMode == TOUCH_MODE_FLING) { 3603 return true; 3604 } 3605 break; 3606 } 3607 3608 case MotionEvent.ACTION_MOVE: { 3609 switch (mTouchMode) { 3610 case TOUCH_MODE_DOWN: 3611 int pointerIndex = ev.findPointerIndex(mActivePointerId); 3612 if (pointerIndex == -1) { 3613 pointerIndex = 0; 3614 mActivePointerId = ev.getPointerId(pointerIndex); 3615 } 3616 final int y = (int) ev.getY(pointerIndex); 3617 initVelocityTrackerIfNotExists(); 3618 mVelocityTracker.addMovement(ev); 3619 if (startScrollIfNeeded(y)) { 3620 return true; 3621 } 3622 break; 3623 } 3624 break; 3625 } 3626 3627 case MotionEvent.ACTION_CANCEL: 3628 case MotionEvent.ACTION_UP: { 3629 mTouchMode = TOUCH_MODE_REST; 3630 mActivePointerId = INVALID_POINTER; 3631 recycleVelocityTracker(); 3632 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 3633 break; 3634 } 3635 3636 case MotionEvent.ACTION_POINTER_UP: { 3637 onSecondaryPointerUp(ev); 3638 break; 3639 } 3640 } 3641 3642 return false; 3643 } 3644 3645 private void onSecondaryPointerUp(MotionEvent ev) { 3646 final int pointerIndex = (ev.getAction() & MotionEvent.ACTION_POINTER_INDEX_MASK) >> 3647 MotionEvent.ACTION_POINTER_INDEX_SHIFT; 3648 final int pointerId = ev.getPointerId(pointerIndex); 3649 if (pointerId == mActivePointerId) { 3650 // This was our active pointer going up. Choose a new 3651 // active pointer and adjust accordingly. 3652 // TODO: Make this decision more intelligent. 3653 final int newPointerIndex = pointerIndex == 0 ? 1 : 0; 3654 mMotionX = (int) ev.getX(newPointerIndex); 3655 mMotionY = (int) ev.getY(newPointerIndex); 3656 mMotionCorrection = 0; 3657 mActivePointerId = ev.getPointerId(newPointerIndex); 3658 } 3659 } 3660 3661 /** 3662 * {@inheritDoc} 3663 */ 3664 @Override 3665 public void addTouchables(ArrayList<View> views) { 3666 final int count = getChildCount(); 3667 final int firstPosition = mFirstPosition; 3668 final ListAdapter adapter = mAdapter; 3669 3670 if (adapter == null) { 3671 return; 3672 } 3673 3674 for (int i = 0; i < count; i++) { 3675 final View child = getChildAt(i); 3676 if (adapter.isEnabled(firstPosition + i)) { 3677 views.add(child); 3678 } 3679 child.addTouchables(views); 3680 } 3681 } 3682 3683 /** 3684 * Fires an "on scroll state changed" event to the registered 3685 * {@link android.widget.AbsListView.OnScrollListener}, if any. The state change 3686 * is fired only if the specified state is different from the previously known state. 3687 * 3688 * @param newState The new scroll state. 3689 */ 3690 void reportScrollStateChange(int newState) { 3691 if (newState != mLastScrollState) { 3692 if (mOnScrollListener != null) { 3693 mLastScrollState = newState; 3694 mOnScrollListener.onScrollStateChanged(this, newState); 3695 } 3696 } 3697 } 3698 3699 /** 3700 * Responsible for fling behavior. Use {@link #start(int)} to 3701 * initiate a fling. Each frame of the fling is handled in {@link #run()}. 3702 * A FlingRunnable will keep re-posting itself until the fling is done. 3703 * 3704 */ 3705 private class FlingRunnable implements Runnable { 3706 /** 3707 * Tracks the decay of a fling scroll 3708 */ 3709 private final OverScroller mScroller; 3710 3711 /** 3712 * Y value reported by mScroller on the previous fling 3713 */ 3714 private int mLastFlingY; 3715 3716 private final Runnable mCheckFlywheel = new Runnable() { 3717 public void run() { 3718 final int activeId = mActivePointerId; 3719 final VelocityTracker vt = mVelocityTracker; 3720 final OverScroller scroller = mScroller; 3721 if (vt == null || activeId == INVALID_POINTER) { 3722 return; 3723 } 3724 3725 vt.computeCurrentVelocity(1000, mMaximumVelocity); 3726 final float yvel = -vt.getYVelocity(activeId); 3727 3728 if (Math.abs(yvel) >= mMinimumVelocity 3729 && scroller.isScrollingInDirection(0, yvel)) { 3730 // Keep the fling alive a little longer 3731 postDelayed(this, FLYWHEEL_TIMEOUT); 3732 } else { 3733 endFling(); 3734 mTouchMode = TOUCH_MODE_SCROLL; 3735 reportScrollStateChange(OnScrollListener.SCROLL_STATE_TOUCH_SCROLL); 3736 } 3737 } 3738 }; 3739 3740 private static final int FLYWHEEL_TIMEOUT = 40; // milliseconds 3741 3742 FlingRunnable() { 3743 mScroller = new OverScroller(getContext()); 3744 } 3745 3746 void start(int initialVelocity) { 3747 int initialY = initialVelocity < 0 ? Integer.MAX_VALUE : 0; 3748 mLastFlingY = initialY; 3749 mScroller.fling(0, initialY, 0, initialVelocity, 3750 0, Integer.MAX_VALUE, 0, Integer.MAX_VALUE); 3751 mTouchMode = TOUCH_MODE_FLING; 3752 post(this); 3753 3754 if (PROFILE_FLINGING) { 3755 if (!mFlingProfilingStarted) { 3756 Debug.startMethodTracing("AbsListViewFling"); 3757 mFlingProfilingStarted = true; 3758 } 3759 } 3760 3761 if (mFlingStrictSpan == null) { 3762 mFlingStrictSpan = StrictMode.enterCriticalSpan("AbsListView-fling"); 3763 } 3764 } 3765 3766 void startSpringback() { 3767 if (mScroller.springBack(0, mScrollY, 0, 0, 0, 0)) { 3768 mTouchMode = TOUCH_MODE_OVERFLING; 3769 invalidate(); 3770 post(this); 3771 } else { 3772 mTouchMode = TOUCH_MODE_REST; 3773 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 3774 } 3775 } 3776 3777 void startOverfling(int initialVelocity) { 3778 mScroller.fling(0, mScrollY, 0, initialVelocity, 0, 0, 3779 Integer.MIN_VALUE, Integer.MAX_VALUE, 0, getHeight()); 3780 mTouchMode = TOUCH_MODE_OVERFLING; 3781 invalidate(); 3782 post(this); 3783 } 3784 3785 void edgeReached(int delta) { 3786 mScroller.notifyVerticalEdgeReached(mScrollY, 0, mOverflingDistance); 3787 final int overscrollMode = getOverScrollMode(); 3788 if (overscrollMode == OVER_SCROLL_ALWAYS || 3789 (overscrollMode == OVER_SCROLL_IF_CONTENT_SCROLLS && !contentFits())) { 3790 mTouchMode = TOUCH_MODE_OVERFLING; 3791 final int vel = (int) mScroller.getCurrVelocity(); 3792 if (delta > 0) { 3793 mEdgeGlowTop.onAbsorb(vel); 3794 } else { 3795 mEdgeGlowBottom.onAbsorb(vel); 3796 } 3797 } else { 3798 mTouchMode = TOUCH_MODE_REST; 3799 if (mPositionScroller != null) { 3800 mPositionScroller.stop(); 3801 } 3802 } 3803 invalidate(); 3804 post(this); 3805 } 3806 3807 void startScroll(int distance, int duration) { 3808 int initialY = distance < 0 ? Integer.MAX_VALUE : 0; 3809 mLastFlingY = initialY; 3810 mScroller.startScroll(0, initialY, 0, distance, duration); 3811 mTouchMode = TOUCH_MODE_FLING; 3812 post(this); 3813 } 3814 3815 void endFling() { 3816 mTouchMode = TOUCH_MODE_REST; 3817 3818 removeCallbacks(this); 3819 removeCallbacks(mCheckFlywheel); 3820 3821 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 3822 clearScrollingCache(); 3823 mScroller.abortAnimation(); 3824 3825 if (mFlingStrictSpan != null) { 3826 mFlingStrictSpan.finish(); 3827 mFlingStrictSpan = null; 3828 } 3829 } 3830 3831 void flywheelTouch() { 3832 postDelayed(mCheckFlywheel, FLYWHEEL_TIMEOUT); 3833 } 3834 3835 public void run() { 3836 switch (mTouchMode) { 3837 default: 3838 endFling(); 3839 return; 3840 3841 case TOUCH_MODE_SCROLL: 3842 if (mScroller.isFinished()) { 3843 return; 3844 } 3845 // Fall through 3846 case TOUCH_MODE_FLING: { 3847 if (mDataChanged) { 3848 layoutChildren(); 3849 } 3850 3851 if (mItemCount == 0 || getChildCount() == 0) { 3852 endFling(); 3853 return; 3854 } 3855 3856 final OverScroller scroller = mScroller; 3857 boolean more = scroller.computeScrollOffset(); 3858 final int y = scroller.getCurrY(); 3859 3860 // Flip sign to convert finger direction to list items direction 3861 // (e.g. finger moving down means list is moving towards the top) 3862 int delta = mLastFlingY - y; 3863 3864 // Pretend that each frame of a fling scroll is a touch scroll 3865 if (delta > 0) { 3866 // List is moving towards the top. Use first view as mMotionPosition 3867 mMotionPosition = mFirstPosition; 3868 final View firstView = getChildAt(0); 3869 mMotionViewOriginalTop = firstView.getTop(); 3870 3871 // Don't fling more than 1 screen 3872 delta = Math.min(getHeight() - mPaddingBottom - mPaddingTop - 1, delta); 3873 } else { 3874 // List is moving towards the bottom. Use last view as mMotionPosition 3875 int offsetToLast = getChildCount() - 1; 3876 mMotionPosition = mFirstPosition + offsetToLast; 3877 3878 final View lastView = getChildAt(offsetToLast); 3879 mMotionViewOriginalTop = lastView.getTop(); 3880 3881 // Don't fling more than 1 screen 3882 delta = Math.max(-(getHeight() - mPaddingBottom - mPaddingTop - 1), delta); 3883 } 3884 3885 // Check to see if we have bumped into the scroll limit 3886 View motionView = getChildAt(mMotionPosition - mFirstPosition); 3887 int oldTop = 0; 3888 if (motionView != null) { 3889 oldTop = motionView.getTop(); 3890 } 3891 3892 // Don't stop just because delta is zero (it could have been rounded) 3893 final boolean atEdge = trackMotionScroll(delta, delta); 3894 final boolean atEnd = atEdge && (delta != 0); 3895 if (atEnd) { 3896 if (motionView != null) { 3897 // Tweak the scroll for how far we overshot 3898 int overshoot = -(delta - (motionView.getTop() - oldTop)); 3899 overScrollBy(0, overshoot, 0, mScrollY, 0, 0, 3900 0, mOverflingDistance, false); 3901 } 3902 if (more) { 3903 edgeReached(delta); 3904 } 3905 break; 3906 } 3907 3908 if (more && !atEnd) { 3909 if (atEdge) invalidate(); 3910 mLastFlingY = y; 3911 post(this); 3912 } else { 3913 endFling(); 3914 3915 if (PROFILE_FLINGING) { 3916 if (mFlingProfilingStarted) { 3917 Debug.stopMethodTracing(); 3918 mFlingProfilingStarted = false; 3919 } 3920 3921 if (mFlingStrictSpan != null) { 3922 mFlingStrictSpan.finish(); 3923 mFlingStrictSpan = null; 3924 } 3925 } 3926 } 3927 break; 3928 } 3929 3930 case TOUCH_MODE_OVERFLING: { 3931 final OverScroller scroller = mScroller; 3932 if (scroller.computeScrollOffset()) { 3933 final int scrollY = mScrollY; 3934 final int currY = scroller.getCurrY(); 3935 final int deltaY = currY - scrollY; 3936 if (overScrollBy(0, deltaY, 0, scrollY, 0, 0, 3937 0, mOverflingDistance, false)) { 3938 final boolean crossDown = scrollY <= 0 && currY > 0; 3939 final boolean crossUp = scrollY >= 0 && currY < 0; 3940 if (crossDown || crossUp) { 3941 int velocity = (int) scroller.getCurrVelocity(); 3942 if (crossUp) velocity = -velocity; 3943 3944 // Don't flywheel from this; we're just continuing things. 3945 scroller.abortAnimation(); 3946 start(velocity); 3947 } else { 3948 startSpringback(); 3949 } 3950 } else { 3951 invalidate(); 3952 post(this); 3953 } 3954 } else { 3955 endFling(); 3956 } 3957 break; 3958 } 3959 } 3960 } 3961 } 3962 3963 3964 class PositionScroller implements Runnable { 3965 private static final int SCROLL_DURATION = 400; 3966 3967 private static final int MOVE_DOWN_POS = 1; 3968 private static final int MOVE_UP_POS = 2; 3969 private static final int MOVE_DOWN_BOUND = 3; 3970 private static final int MOVE_UP_BOUND = 4; 3971 private static final int MOVE_OFFSET = 5; 3972 3973 private int mMode; 3974 private int mTargetPos; 3975 private int mBoundPos; 3976 private int mLastSeenPos; 3977 private int mScrollDuration; 3978 private final int mExtraScroll; 3979 3980 private int mOffsetFromTop; 3981 3982 PositionScroller() { 3983 mExtraScroll = ViewConfiguration.get(mContext).getScaledFadingEdgeLength(); 3984 } 3985 3986 void start(int position) { 3987 stop(); 3988 3989 final int firstPos = mFirstPosition; 3990 final int lastPos = firstPos + getChildCount() - 1; 3991 3992 int viewTravelCount; 3993 if (position <= firstPos) { 3994 viewTravelCount = firstPos - position + 1; 3995 mMode = MOVE_UP_POS; 3996 } else if (position >= lastPos) { 3997 viewTravelCount = position - lastPos + 1; 3998 mMode = MOVE_DOWN_POS; 3999 } else { 4000 // Already on screen, nothing to do 4001 return; 4002 } 4003 4004 if (viewTravelCount > 0) { 4005 mScrollDuration = SCROLL_DURATION / viewTravelCount; 4006 } else { 4007 mScrollDuration = SCROLL_DURATION; 4008 } 4009 mTargetPos = position; 4010 mBoundPos = INVALID_POSITION; 4011 mLastSeenPos = INVALID_POSITION; 4012 4013 post(this); 4014 } 4015 4016 void start(int position, int boundPosition) { 4017 stop(); 4018 4019 if (boundPosition == INVALID_POSITION) { 4020 start(position); 4021 return; 4022 } 4023 4024 final int firstPos = mFirstPosition; 4025 final int lastPos = firstPos + getChildCount() - 1; 4026 4027 int viewTravelCount; 4028 if (position <= firstPos) { 4029 final int boundPosFromLast = lastPos - boundPosition; 4030 if (boundPosFromLast < 1) { 4031 // Moving would shift our bound position off the screen. Abort. 4032 return; 4033 } 4034 4035 final int posTravel = firstPos - position + 1; 4036 final int boundTravel = boundPosFromLast - 1; 4037 if (boundTravel < posTravel) { 4038 viewTravelCount = boundTravel; 4039 mMode = MOVE_UP_BOUND; 4040 } else { 4041 viewTravelCount = posTravel; 4042 mMode = MOVE_UP_POS; 4043 } 4044 } else if (position >= lastPos) { 4045 final int boundPosFromFirst = boundPosition - firstPos; 4046 if (boundPosFromFirst < 1) { 4047 // Moving would shift our bound position off the screen. Abort. 4048 return; 4049 } 4050 4051 final int posTravel = position - lastPos + 1; 4052 final int boundTravel = boundPosFromFirst - 1; 4053 if (boundTravel < posTravel) { 4054 viewTravelCount = boundTravel; 4055 mMode = MOVE_DOWN_BOUND; 4056 } else { 4057 viewTravelCount = posTravel; 4058 mMode = MOVE_DOWN_POS; 4059 } 4060 } else { 4061 // Already on screen, nothing to do 4062 return; 4063 } 4064 4065 if (viewTravelCount > 0) { 4066 mScrollDuration = SCROLL_DURATION / viewTravelCount; 4067 } else { 4068 mScrollDuration = SCROLL_DURATION; 4069 } 4070 mTargetPos = position; 4071 mBoundPos = boundPosition; 4072 mLastSeenPos = INVALID_POSITION; 4073 4074 post(this); 4075 } 4076 4077 void startWithOffset(int position, int offset) { 4078 startWithOffset(position, offset, SCROLL_DURATION); 4079 } 4080 4081 void startWithOffset(int position, int offset, int duration) { 4082 stop(); 4083 4084 mTargetPos = position; 4085 mOffsetFromTop = offset; 4086 mBoundPos = INVALID_POSITION; 4087 mLastSeenPos = INVALID_POSITION; 4088 mMode = MOVE_OFFSET; 4089 4090 final int firstPos = mFirstPosition; 4091 final int childCount = getChildCount(); 4092 final int lastPos = firstPos + childCount - 1; 4093 4094 int viewTravelCount; 4095 if (position < firstPos) { 4096 viewTravelCount = firstPos - position; 4097 } else if (position > lastPos) { 4098 viewTravelCount = position - lastPos; 4099 } else { 4100 // On-screen, just scroll. 4101 final int targetTop = getChildAt(position - firstPos).getTop(); 4102 smoothScrollBy(targetTop - offset, duration); 4103 return; 4104 } 4105 4106 // Estimate how many screens we should travel 4107 final float screenTravelCount = (float) viewTravelCount / childCount; 4108 mScrollDuration = screenTravelCount < 1 ? (int) (screenTravelCount * duration) : 4109 (int) (duration / screenTravelCount); 4110 mLastSeenPos = INVALID_POSITION; 4111 4112 post(this); 4113 } 4114 4115 void stop() { 4116 removeCallbacks(this); 4117 } 4118 4119 public void run() { 4120 if (mTouchMode != TOUCH_MODE_FLING && mLastSeenPos != INVALID_POSITION) { 4121 return; 4122 } 4123 4124 final int listHeight = getHeight(); 4125 final int firstPos = mFirstPosition; 4126 4127 switch (mMode) { 4128 case MOVE_DOWN_POS: { 4129 final int lastViewIndex = getChildCount() - 1; 4130 final int lastPos = firstPos + lastViewIndex; 4131 4132 if (lastViewIndex < 0) { 4133 return; 4134 } 4135 4136 if (lastPos == mLastSeenPos) { 4137 // No new views, let things keep going. 4138 post(this); 4139 return; 4140 } 4141 4142 final View lastView = getChildAt(lastViewIndex); 4143 final int lastViewHeight = lastView.getHeight(); 4144 final int lastViewTop = lastView.getTop(); 4145 final int lastViewPixelsShowing = listHeight - lastViewTop; 4146 final int extraScroll = lastPos < mItemCount - 1 ? mExtraScroll : mListPadding.bottom; 4147 4148 smoothScrollBy(lastViewHeight - lastViewPixelsShowing + extraScroll, 4149 mScrollDuration); 4150 4151 mLastSeenPos = lastPos; 4152 if (lastPos < mTargetPos) { 4153 post(this); 4154 } 4155 break; 4156 } 4157 4158 case MOVE_DOWN_BOUND: { 4159 final int nextViewIndex = 1; 4160 final int childCount = getChildCount(); 4161 4162 if (firstPos == mBoundPos || childCount <= nextViewIndex 4163 || firstPos + childCount >= mItemCount) { 4164 return; 4165 } 4166 final int nextPos = firstPos + nextViewIndex; 4167 4168 if (nextPos == mLastSeenPos) { 4169 // No new views, let things keep going. 4170 post(this); 4171 return; 4172 } 4173 4174 final View nextView = getChildAt(nextViewIndex); 4175 final int nextViewHeight = nextView.getHeight(); 4176 final int nextViewTop = nextView.getTop(); 4177 final int extraScroll = mExtraScroll; 4178 if (nextPos < mBoundPos) { 4179 smoothScrollBy(Math.max(0, nextViewHeight + nextViewTop - extraScroll), 4180 mScrollDuration); 4181 4182 mLastSeenPos = nextPos; 4183 4184 post(this); 4185 } else { 4186 if (nextViewTop > extraScroll) { 4187 smoothScrollBy(nextViewTop - extraScroll, mScrollDuration); 4188 } 4189 } 4190 break; 4191 } 4192 4193 case MOVE_UP_POS: { 4194 if (firstPos == mLastSeenPos) { 4195 // No new views, let things keep going. 4196 post(this); 4197 return; 4198 } 4199 4200 final View firstView = getChildAt(0); 4201 if (firstView == null) { 4202 return; 4203 } 4204 final int firstViewTop = firstView.getTop(); 4205 final int extraScroll = firstPos > 0 ? mExtraScroll : mListPadding.top; 4206 4207 smoothScrollBy(firstViewTop - extraScroll, mScrollDuration); 4208 4209 mLastSeenPos = firstPos; 4210 4211 if (firstPos > mTargetPos) { 4212 post(this); 4213 } 4214 break; 4215 } 4216 4217 case MOVE_UP_BOUND: { 4218 final int lastViewIndex = getChildCount() - 2; 4219 if (lastViewIndex < 0) { 4220 return; 4221 } 4222 final int lastPos = firstPos + lastViewIndex; 4223 4224 if (lastPos == mLastSeenPos) { 4225 // No new views, let things keep going. 4226 post(this); 4227 return; 4228 } 4229 4230 final View lastView = getChildAt(lastViewIndex); 4231 final int lastViewHeight = lastView.getHeight(); 4232 final int lastViewTop = lastView.getTop(); 4233 final int lastViewPixelsShowing = listHeight - lastViewTop; 4234 mLastSeenPos = lastPos; 4235 if (lastPos > mBoundPos) { 4236 smoothScrollBy(-(lastViewPixelsShowing - mExtraScroll), mScrollDuration); 4237 post(this); 4238 } else { 4239 final int bottom = listHeight - mExtraScroll; 4240 final int lastViewBottom = lastViewTop + lastViewHeight; 4241 if (bottom > lastViewBottom) { 4242 smoothScrollBy(-(bottom - lastViewBottom), mScrollDuration); 4243 } 4244 } 4245 break; 4246 } 4247 4248 case MOVE_OFFSET: { 4249 if (mLastSeenPos == firstPos) { 4250 // No new views, let things keep going. 4251 post(this); 4252 return; 4253 } 4254 4255 mLastSeenPos = firstPos; 4256 4257 final int childCount = getChildCount(); 4258 final int position = mTargetPos; 4259 final int lastPos = firstPos + childCount - 1; 4260 4261 int viewTravelCount = 0; 4262 if (position < firstPos) { 4263 viewTravelCount = firstPos - position + 1; 4264 } else if (position > lastPos) { 4265 viewTravelCount = position - lastPos; 4266 } 4267 4268 // Estimate how many screens we should travel 4269 final float screenTravelCount = (float) viewTravelCount / childCount; 4270 4271 final float modifier = Math.min(Math.abs(screenTravelCount), 1.f); 4272 if (position < firstPos) { 4273 smoothScrollBy((int) (-getHeight() * modifier), mScrollDuration); 4274 post(this); 4275 } else if (position > lastPos) { 4276 smoothScrollBy((int) (getHeight() * modifier), mScrollDuration); 4277 post(this); 4278 } else { 4279 // On-screen, just scroll. 4280 final int targetTop = getChildAt(position - firstPos).getTop(); 4281 final int distance = targetTop - mOffsetFromTop; 4282 smoothScrollBy(distance, 4283 (int) (mScrollDuration * ((float) distance / getHeight()))); 4284 } 4285 break; 4286 } 4287 4288 default: 4289 break; 4290 } 4291 } 4292 } 4293 4294 /** 4295 * The amount of friction applied to flings. The default value 4296 * is {@link ViewConfiguration#getScrollFriction}. 4297 * 4298 * @return A scalar dimensionless value representing the coefficient of 4299 * friction. 4300 */ 4301 public void setFriction(float friction) { 4302 if (mFlingRunnable == null) { 4303 mFlingRunnable = new FlingRunnable(); 4304 } 4305 mFlingRunnable.mScroller.setFriction(friction); 4306 } 4307 4308 /** 4309 * Sets a scale factor for the fling velocity. The initial scale 4310 * factor is 1.0. 4311 * 4312 * @param scale The scale factor to multiply the velocity by. 4313 */ 4314 public void setVelocityScale(float scale) { 4315 mVelocityScale = scale; 4316 } 4317 4318 /** 4319 * Smoothly scroll to the specified adapter position. The view will 4320 * scroll such that the indicated position is displayed. 4321 * @param position Scroll to this adapter position. 4322 */ 4323 public void smoothScrollToPosition(int position) { 4324 if (mPositionScroller == null) { 4325 mPositionScroller = new PositionScroller(); 4326 } 4327 mPositionScroller.start(position); 4328 } 4329 4330 /** 4331 * Smoothly scroll to the specified adapter position. The view will scroll 4332 * such that the indicated position is displayed <code>offset</code> pixels from 4333 * the top edge of the view. If this is impossible, (e.g. the offset would scroll 4334 * the first or last item beyond the boundaries of the list) it will get as close 4335 * as possible. The scroll will take <code>duration</code> milliseconds to complete. 4336 * 4337 * @param position Position to scroll to 4338 * @param offset Desired distance in pixels of <code>position</code> from the top 4339 * of the view when scrolling is finished 4340 * @param duration Number of milliseconds to use for the scroll 4341 */ 4342 public void smoothScrollToPositionFromTop(int position, int offset, int duration) { 4343 if (mPositionScroller == null) { 4344 mPositionScroller = new PositionScroller(); 4345 } 4346 mPositionScroller.startWithOffset(position, offset, duration); 4347 } 4348 4349 /** 4350 * Smoothly scroll to the specified adapter position. The view will scroll 4351 * such that the indicated position is displayed <code>offset</code> pixels from 4352 * the top edge of the view. If this is impossible, (e.g. the offset would scroll 4353 * the first or last item beyond the boundaries of the list) it will get as close 4354 * as possible. 4355 * 4356 * @param position Position to scroll to 4357 * @param offset Desired distance in pixels of <code>position</code> from the top 4358 * of the view when scrolling is finished 4359 */ 4360 public void smoothScrollToPositionFromTop(int position, int offset) { 4361 if (mPositionScroller == null) { 4362 mPositionScroller = new PositionScroller(); 4363 } 4364 mPositionScroller.startWithOffset(position, offset); 4365 } 4366 4367 /** 4368 * Smoothly scroll to the specified adapter position. The view will 4369 * scroll such that the indicated position is displayed, but it will 4370 * stop early if scrolling further would scroll boundPosition out of 4371 * view. 4372 * @param position Scroll to this adapter position. 4373 * @param boundPosition Do not scroll if it would move this adapter 4374 * position out of view. 4375 */ 4376 public void smoothScrollToPosition(int position, int boundPosition) { 4377 if (mPositionScroller == null) { 4378 mPositionScroller = new PositionScroller(); 4379 } 4380 mPositionScroller.start(position, boundPosition); 4381 } 4382 4383 /** 4384 * Smoothly scroll by distance pixels over duration milliseconds. 4385 * @param distance Distance to scroll in pixels. 4386 * @param duration Duration of the scroll animation in milliseconds. 4387 */ 4388 public void smoothScrollBy(int distance, int duration) { 4389 if (mFlingRunnable == null) { 4390 mFlingRunnable = new FlingRunnable(); 4391 } 4392 4393 // No sense starting to scroll if we're not going anywhere 4394 final int firstPos = mFirstPosition; 4395 final int childCount = getChildCount(); 4396 final int lastPos = firstPos + childCount; 4397 final int topLimit = getPaddingTop(); 4398 final int bottomLimit = getHeight() - getPaddingBottom(); 4399 4400 if (distance == 0 || mItemCount == 0 || childCount == 0 || 4401 (firstPos == 0 && getChildAt(0).getTop() == topLimit && distance < 0) || 4402 (lastPos == mItemCount - 1 && 4403 getChildAt(childCount - 1).getBottom() == bottomLimit && distance > 0)) { 4404 mFlingRunnable.endFling(); 4405 if (mPositionScroller != null) { 4406 mPositionScroller.stop(); 4407 } 4408 } else { 4409 reportScrollStateChange(OnScrollListener.SCROLL_STATE_FLING); 4410 mFlingRunnable.startScroll(distance, duration); 4411 } 4412 } 4413 4414 /** 4415 * Allows RemoteViews to scroll relatively to a position. 4416 */ 4417 void smoothScrollByOffset(int position) { 4418 int index = -1; 4419 if (position < 0) { 4420 index = getFirstVisiblePosition(); 4421 } else if (position > 0) { 4422 index = getLastVisiblePosition(); 4423 } 4424 4425 if (index > -1) { 4426 View child = getChildAt(index - getFirstVisiblePosition()); 4427 if (child != null) { 4428 Rect visibleRect = new Rect(); 4429 if (child.getGlobalVisibleRect(visibleRect)) { 4430 // the child is partially visible 4431 int childRectArea = child.getWidth() * child.getHeight(); 4432 int visibleRectArea = visibleRect.width() * visibleRect.height(); 4433 float visibleArea = (visibleRectArea / (float) childRectArea); 4434 final float visibleThreshold = 0.75f; 4435 if ((position < 0) && (visibleArea < visibleThreshold)) { 4436 // the top index is not perceivably visible so offset 4437 // to account for showing that top index as well 4438 ++index; 4439 } else if ((position > 0) && (visibleArea < visibleThreshold)) { 4440 // the bottom index is not perceivably visible so offset 4441 // to account for showing that bottom index as well 4442 --index; 4443 } 4444 } 4445 smoothScrollToPosition(Math.max(0, Math.min(getCount(), index + position))); 4446 } 4447 } 4448 } 4449 4450 private void createScrollingCache() { 4451 if (mScrollingCacheEnabled && !mCachingStarted && !isHardwareAccelerated()) { 4452 setChildrenDrawnWithCacheEnabled(true); 4453 setChildrenDrawingCacheEnabled(true); 4454 mCachingStarted = mCachingActive = true; 4455 } 4456 } 4457 4458 private void clearScrollingCache() { 4459 if (!isHardwareAccelerated()) { 4460 if (mClearScrollingCache == null) { 4461 mClearScrollingCache = new Runnable() { 4462 public void run() { 4463 if (mCachingStarted) { 4464 mCachingStarted = mCachingActive = false; 4465 setChildrenDrawnWithCacheEnabled(false); 4466 if ((mPersistentDrawingCache & PERSISTENT_SCROLLING_CACHE) == 0) { 4467 setChildrenDrawingCacheEnabled(false); 4468 } 4469 if (!isAlwaysDrawnWithCacheEnabled()) { 4470 invalidate(); 4471 } 4472 } 4473 } 4474 }; 4475 } 4476 post(mClearScrollingCache); 4477 } 4478 } 4479 4480 /** 4481 * Track a motion scroll 4482 * 4483 * @param deltaY Amount to offset mMotionView. This is the accumulated delta since the motion 4484 * began. Positive numbers mean the user's finger is moving down the screen. 4485 * @param incrementalDeltaY Change in deltaY from the previous event. 4486 * @return true if we're already at the beginning/end of the list and have nothing to do. 4487 */ 4488 boolean trackMotionScroll(int deltaY, int incrementalDeltaY) { 4489 final int childCount = getChildCount(); 4490 if (childCount == 0) { 4491 return true; 4492 } 4493 4494 final int firstTop = getChildAt(0).getTop(); 4495 final int lastBottom = getChildAt(childCount - 1).getBottom(); 4496 4497 final Rect listPadding = mListPadding; 4498 4499 // "effective padding" In this case is the amount of padding that affects 4500 // how much space should not be filled by items. If we don't clip to padding 4501 // there is no effective padding. 4502 int effectivePaddingTop = 0; 4503 int effectivePaddingBottom = 0; 4504 if ((mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK) { 4505 effectivePaddingTop = listPadding.top; 4506 effectivePaddingBottom = listPadding.bottom; 4507 } 4508 4509 // FIXME account for grid vertical spacing too? 4510 final int spaceAbove = effectivePaddingTop - firstTop; 4511 final int end = getHeight() - effectivePaddingBottom; 4512 final int spaceBelow = lastBottom - end; 4513 4514 final int height = getHeight() - mPaddingBottom - mPaddingTop; 4515 if (deltaY < 0) { 4516 deltaY = Math.max(-(height - 1), deltaY); 4517 } else { 4518 deltaY = Math.min(height - 1, deltaY); 4519 } 4520 4521 if (incrementalDeltaY < 0) { 4522 incrementalDeltaY = Math.max(-(height - 1), incrementalDeltaY); 4523 } else { 4524 incrementalDeltaY = Math.min(height - 1, incrementalDeltaY); 4525 } 4526 4527 final int firstPosition = mFirstPosition; 4528 4529 // Update our guesses for where the first and last views are 4530 if (firstPosition == 0) { 4531 mFirstPositionDistanceGuess = firstTop - listPadding.top; 4532 } else { 4533 mFirstPositionDistanceGuess += incrementalDeltaY; 4534 } 4535 if (firstPosition + childCount == mItemCount) { 4536 mLastPositionDistanceGuess = lastBottom + listPadding.bottom; 4537 } else { 4538 mLastPositionDistanceGuess += incrementalDeltaY; 4539 } 4540 4541 final boolean cannotScrollDown = (firstPosition == 0 && 4542 firstTop >= listPadding.top && incrementalDeltaY >= 0); 4543 final boolean cannotScrollUp = (firstPosition + childCount == mItemCount && 4544 lastBottom <= getHeight() - listPadding.bottom && incrementalDeltaY <= 0); 4545 4546 if (cannotScrollDown || cannotScrollUp) { 4547 return incrementalDeltaY != 0; 4548 } 4549 4550 final boolean down = incrementalDeltaY < 0; 4551 4552 final boolean inTouchMode = isInTouchMode(); 4553 if (inTouchMode) { 4554 hideSelector(); 4555 } 4556 4557 final int headerViewsCount = getHeaderViewsCount(); 4558 final int footerViewsStart = mItemCount - getFooterViewsCount(); 4559 4560 int start = 0; 4561 int count = 0; 4562 4563 if (down) { 4564 int top = -incrementalDeltaY; 4565 if ((mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK) { 4566 top += listPadding.top; 4567 } 4568 for (int i = 0; i < childCount; i++) { 4569 final View child = getChildAt(i); 4570 if (child.getBottom() >= top) { 4571 break; 4572 } else { 4573 count++; 4574 int position = firstPosition + i; 4575 if (position >= headerViewsCount && position < footerViewsStart) { 4576 mRecycler.addScrapView(child, position); 4577 4578 if (ViewDebug.TRACE_RECYCLER) { 4579 ViewDebug.trace(child, 4580 ViewDebug.RecyclerTraceType.MOVE_TO_SCRAP_HEAP, 4581 firstPosition + i, -1); 4582 } 4583 } 4584 } 4585 } 4586 } else { 4587 int bottom = getHeight() - incrementalDeltaY; 4588 if ((mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK) { 4589 bottom -= listPadding.bottom; 4590 } 4591 for (int i = childCount - 1; i >= 0; i--) { 4592 final View child = getChildAt(i); 4593 if (child.getTop() <= bottom) { 4594 break; 4595 } else { 4596 start = i; 4597 count++; 4598 int position = firstPosition + i; 4599 if (position >= headerViewsCount && position < footerViewsStart) { 4600 mRecycler.addScrapView(child, position); 4601 4602 if (ViewDebug.TRACE_RECYCLER) { 4603 ViewDebug.trace(child, 4604 ViewDebug.RecyclerTraceType.MOVE_TO_SCRAP_HEAP, 4605 firstPosition + i, -1); 4606 } 4607 } 4608 } 4609 } 4610 } 4611 4612 mMotionViewNewTop = mMotionViewOriginalTop + deltaY; 4613 4614 mBlockLayoutRequests = true; 4615 4616 if (count > 0) { 4617 detachViewsFromParent(start, count); 4618 mRecycler.removeSkippedScrap(); 4619 } 4620 4621 // invalidate before moving the children to avoid unnecessary invalidate 4622 // calls to bubble up from the children all the way to the top 4623 if (!awakenScrollBars()) { 4624 invalidate(); 4625 } 4626 4627 offsetChildrenTopAndBottom(incrementalDeltaY); 4628 4629 if (down) { 4630 mFirstPosition += count; 4631 } 4632 4633 final int absIncrementalDeltaY = Math.abs(incrementalDeltaY); 4634 if (spaceAbove < absIncrementalDeltaY || spaceBelow < absIncrementalDeltaY) { 4635 fillGap(down); 4636 } 4637 4638 if (!inTouchMode && mSelectedPosition != INVALID_POSITION) { 4639 final int childIndex = mSelectedPosition - mFirstPosition; 4640 if (childIndex >= 0 && childIndex < getChildCount()) { 4641 positionSelector(mSelectedPosition, getChildAt(childIndex)); 4642 } 4643 } else if (mSelectorPosition != INVALID_POSITION) { 4644 final int childIndex = mSelectorPosition - mFirstPosition; 4645 if (childIndex >= 0 && childIndex < getChildCount()) { 4646 positionSelector(INVALID_POSITION, getChildAt(childIndex)); 4647 } 4648 } else { 4649 mSelectorRect.setEmpty(); 4650 } 4651 4652 mBlockLayoutRequests = false; 4653 4654 invokeOnItemScrollListener(); 4655 4656 return false; 4657 } 4658 4659 /** 4660 * Returns the number of header views in the list. Header views are special views 4661 * at the top of the list that should not be recycled during a layout. 4662 * 4663 * @return The number of header views, 0 in the default implementation. 4664 */ 4665 int getHeaderViewsCount() { 4666 return 0; 4667 } 4668 4669 /** 4670 * Returns the number of footer views in the list. Footer views are special views 4671 * at the bottom of the list that should not be recycled during a layout. 4672 * 4673 * @return The number of footer views, 0 in the default implementation. 4674 */ 4675 int getFooterViewsCount() { 4676 return 0; 4677 } 4678 4679 /** 4680 * Fills the gap left open by a touch-scroll. During a touch scroll, children that 4681 * remain on screen are shifted and the other ones are discarded. The role of this 4682 * method is to fill the gap thus created by performing a partial layout in the 4683 * empty space. 4684 * 4685 * @param down true if the scroll is going down, false if it is going up 4686 */ 4687 abstract void fillGap(boolean down); 4688 4689 void hideSelector() { 4690 if (mSelectedPosition != INVALID_POSITION) { 4691 if (mLayoutMode != LAYOUT_SPECIFIC) { 4692 mResurrectToPosition = mSelectedPosition; 4693 } 4694 if (mNextSelectedPosition >= 0 && mNextSelectedPosition != mSelectedPosition) { 4695 mResurrectToPosition = mNextSelectedPosition; 4696 } 4697 setSelectedPositionInt(INVALID_POSITION); 4698 setNextSelectedPositionInt(INVALID_POSITION); 4699 mSelectedTop = 0; 4700 } 4701 } 4702 4703 /** 4704 * @return A position to select. First we try mSelectedPosition. If that has been clobbered by 4705 * entering touch mode, we then try mResurrectToPosition. Values are pinned to the range 4706 * of items available in the adapter 4707 */ 4708 int reconcileSelectedPosition() { 4709 int position = mSelectedPosition; 4710 if (position < 0) { 4711 position = mResurrectToPosition; 4712 } 4713 position = Math.max(0, position); 4714 position = Math.min(position, mItemCount - 1); 4715 return position; 4716 } 4717 4718 /** 4719 * Find the row closest to y. This row will be used as the motion row when scrolling 4720 * 4721 * @param y Where the user touched 4722 * @return The position of the first (or only) item in the row containing y 4723 */ 4724 abstract int findMotionRow(int y); 4725 4726 /** 4727 * Find the row closest to y. This row will be used as the motion row when scrolling. 4728 * 4729 * @param y Where the user touched 4730 * @return The position of the first (or only) item in the row closest to y 4731 */ 4732 int findClosestMotionRow(int y) { 4733 final int childCount = getChildCount(); 4734 if (childCount == 0) { 4735 return INVALID_POSITION; 4736 } 4737 4738 final int motionRow = findMotionRow(y); 4739 return motionRow != INVALID_POSITION ? motionRow : mFirstPosition + childCount - 1; 4740 } 4741 4742 /** 4743 * Causes all the views to be rebuilt and redrawn. 4744 */ 4745 public void invalidateViews() { 4746 mDataChanged = true; 4747 rememberSyncState(); 4748 requestLayout(); 4749 invalidate(); 4750 } 4751 4752 /** 4753 * If there is a selection returns false. 4754 * Otherwise resurrects the selection and returns true if resurrected. 4755 */ 4756 boolean resurrectSelectionIfNeeded() { 4757 if (mSelectedPosition < 0 && resurrectSelection()) { 4758 updateSelectorState(); 4759 return true; 4760 } 4761 return false; 4762 } 4763 4764 /** 4765 * Makes the item at the supplied position selected. 4766 * 4767 * @param position the position of the new selection 4768 */ 4769 abstract void setSelectionInt(int position); 4770 4771 /** 4772 * Attempt to bring the selection back if the user is switching from touch 4773 * to trackball mode 4774 * @return Whether selection was set to something. 4775 */ 4776 boolean resurrectSelection() { 4777 final int childCount = getChildCount(); 4778 4779 if (childCount <= 0) { 4780 return false; 4781 } 4782 4783 int selectedTop = 0; 4784 int selectedPos; 4785 int childrenTop = mListPadding.top; 4786 int childrenBottom = mBottom - mTop - mListPadding.bottom; 4787 final int firstPosition = mFirstPosition; 4788 final int toPosition = mResurrectToPosition; 4789 boolean down = true; 4790 4791 if (toPosition >= firstPosition && toPosition < firstPosition + childCount) { 4792 selectedPos = toPosition; 4793 4794 final View selected = getChildAt(selectedPos - mFirstPosition); 4795 selectedTop = selected.getTop(); 4796 int selectedBottom = selected.getBottom(); 4797 4798 // We are scrolled, don't get in the fade 4799 if (selectedTop < childrenTop) { 4800 selectedTop = childrenTop + getVerticalFadingEdgeLength(); 4801 } else if (selectedBottom > childrenBottom) { 4802 selectedTop = childrenBottom - selected.getMeasuredHeight() 4803 - getVerticalFadingEdgeLength(); 4804 } 4805 } else { 4806 if (toPosition < firstPosition) { 4807 // Default to selecting whatever is first 4808 selectedPos = firstPosition; 4809 for (int i = 0; i < childCount; i++) { 4810 final View v = getChildAt(i); 4811 final int top = v.getTop(); 4812 4813 if (i == 0) { 4814 // Remember the position of the first item 4815 selectedTop = top; 4816 // See if we are scrolled at all 4817 if (firstPosition > 0 || top < childrenTop) { 4818 // If we are scrolled, don't select anything that is 4819 // in the fade region 4820 childrenTop += getVerticalFadingEdgeLength(); 4821 } 4822 } 4823 if (top >= childrenTop) { 4824 // Found a view whose top is fully visisble 4825 selectedPos = firstPosition + i; 4826 selectedTop = top; 4827 break; 4828 } 4829 } 4830 } else { 4831 final int itemCount = mItemCount; 4832 down = false; 4833 selectedPos = firstPosition + childCount - 1; 4834 4835 for (int i = childCount - 1; i >= 0; i--) { 4836 final View v = getChildAt(i); 4837 final int top = v.getTop(); 4838 final int bottom = v.getBottom(); 4839 4840 if (i == childCount - 1) { 4841 selectedTop = top; 4842 if (firstPosition + childCount < itemCount || bottom > childrenBottom) { 4843 childrenBottom -= getVerticalFadingEdgeLength(); 4844 } 4845 } 4846 4847 if (bottom <= childrenBottom) { 4848 selectedPos = firstPosition + i; 4849 selectedTop = top; 4850 break; 4851 } 4852 } 4853 } 4854 } 4855 4856 mResurrectToPosition = INVALID_POSITION; 4857 removeCallbacks(mFlingRunnable); 4858 if (mPositionScroller != null) { 4859 mPositionScroller.stop(); 4860 } 4861 mTouchMode = TOUCH_MODE_REST; 4862 clearScrollingCache(); 4863 mSpecificTop = selectedTop; 4864 selectedPos = lookForSelectablePosition(selectedPos, down); 4865 if (selectedPos >= firstPosition && selectedPos <= getLastVisiblePosition()) { 4866 mLayoutMode = LAYOUT_SPECIFIC; 4867 updateSelectorState(); 4868 setSelectionInt(selectedPos); 4869 invokeOnItemScrollListener(); 4870 } else { 4871 selectedPos = INVALID_POSITION; 4872 } 4873 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 4874 4875 return selectedPos >= 0; 4876 } 4877 4878 void confirmCheckedPositionsById() { 4879 // Clear out the positional check states, we'll rebuild it below from IDs. 4880 mCheckStates.clear(); 4881 4882 boolean checkedCountChanged = false; 4883 for (int checkedIndex = 0; checkedIndex < mCheckedIdStates.size(); checkedIndex++) { 4884 final long id = mCheckedIdStates.keyAt(checkedIndex); 4885 final int lastPos = mCheckedIdStates.valueAt(checkedIndex); 4886 4887 final long lastPosId = mAdapter.getItemId(lastPos); 4888 if (id != lastPosId) { 4889 // Look around to see if the ID is nearby. If not, uncheck it. 4890 final int start = Math.max(0, lastPos - CHECK_POSITION_SEARCH_DISTANCE); 4891 final int end = Math.min(lastPos + CHECK_POSITION_SEARCH_DISTANCE, mItemCount); 4892 boolean found = false; 4893 for (int searchPos = start; searchPos < end; searchPos++) { 4894 final long searchId = mAdapter.getItemId(searchPos); 4895 if (id == searchId) { 4896 found = true; 4897 mCheckStates.put(searchPos, true); 4898 mCheckedIdStates.setValueAt(checkedIndex, searchPos); 4899 break; 4900 } 4901 } 4902 4903 if (!found) { 4904 mCheckedIdStates.delete(id); 4905 checkedIndex--; 4906 mCheckedItemCount--; 4907 checkedCountChanged = true; 4908 if (mChoiceActionMode != null && mMultiChoiceModeCallback != null) { 4909 mMultiChoiceModeCallback.onItemCheckedStateChanged(mChoiceActionMode, 4910 lastPos, id, false); 4911 } 4912 } 4913 } else { 4914 mCheckStates.put(lastPos, true); 4915 } 4916 } 4917 4918 if (checkedCountChanged && mChoiceActionMode != null) { 4919 mChoiceActionMode.invalidate(); 4920 } 4921 } 4922 4923 @Override 4924 protected void handleDataChanged() { 4925 int count = mItemCount; 4926 int lastHandledItemCount = mLastHandledItemCount; 4927 mLastHandledItemCount = mItemCount; 4928 4929 if (mChoiceMode != CHOICE_MODE_NONE && mAdapter != null && mAdapter.hasStableIds()) { 4930 confirmCheckedPositionsById(); 4931 } 4932 4933 // TODO: In the future we can recycle these views based on stable ID instead. 4934 mRecycler.clearTransientStateViews(); 4935 4936 if (count > 0) { 4937 int newPos; 4938 int selectablePos; 4939 4940 // Find the row we are supposed to sync to 4941 if (mNeedSync) { 4942 // Update this first, since setNextSelectedPositionInt inspects it 4943 mNeedSync = false; 4944 4945 if (mTranscriptMode == TRANSCRIPT_MODE_ALWAYS_SCROLL) { 4946 mLayoutMode = LAYOUT_FORCE_BOTTOM; 4947 return; 4948 } else if (mTranscriptMode == TRANSCRIPT_MODE_NORMAL) { 4949 if (mForceTranscriptScroll) { 4950 mForceTranscriptScroll = false; 4951 mLayoutMode = LAYOUT_FORCE_BOTTOM; 4952 return; 4953 } 4954 final int childCount = getChildCount(); 4955 final int listBottom = getHeight() - getPaddingBottom(); 4956 final View lastChild = getChildAt(childCount - 1); 4957 final int lastBottom = lastChild != null ? lastChild.getBottom() : listBottom; 4958 if (mFirstPosition + childCount >= lastHandledItemCount && 4959 lastBottom <= listBottom) { 4960 mLayoutMode = LAYOUT_FORCE_BOTTOM; 4961 return; 4962 } 4963 // Something new came in and we didn't scroll; give the user a clue that 4964 // there's something new. 4965 awakenScrollBars(); 4966 } 4967 4968 switch (mSyncMode) { 4969 case SYNC_SELECTED_POSITION: 4970 if (isInTouchMode()) { 4971 // We saved our state when not in touch mode. (We know this because 4972 // mSyncMode is SYNC_SELECTED_POSITION.) Now we are trying to 4973 // restore in touch mode. Just leave mSyncPosition as it is (possibly 4974 // adjusting if the available range changed) and return. 4975 mLayoutMode = LAYOUT_SYNC; 4976 mSyncPosition = Math.min(Math.max(0, mSyncPosition), count - 1); 4977 4978 return; 4979 } else { 4980 // See if we can find a position in the new data with the same 4981 // id as the old selection. This will change mSyncPosition. 4982 newPos = findSyncPosition(); 4983 if (newPos >= 0) { 4984 // Found it. Now verify that new selection is still selectable 4985 selectablePos = lookForSelectablePosition(newPos, true); 4986 if (selectablePos == newPos) { 4987 // Same row id is selected 4988 mSyncPosition = newPos; 4989 4990 if (mSyncHeight == getHeight()) { 4991 // If we are at the same height as when we saved state, try 4992 // to restore the scroll position too. 4993 mLayoutMode = LAYOUT_SYNC; 4994 } else { 4995 // We are not the same height as when the selection was saved, so 4996 // don't try to restore the exact position 4997 mLayoutMode = LAYOUT_SET_SELECTION; 4998 } 4999 5000 // Restore selection 5001 setNextSelectedPositionInt(newPos); 5002 return; 5003 } 5004 } 5005 } 5006 break; 5007 case SYNC_FIRST_POSITION: 5008 // Leave mSyncPosition as it is -- just pin to available range 5009 mLayoutMode = LAYOUT_SYNC; 5010 mSyncPosition = Math.min(Math.max(0, mSyncPosition), count - 1); 5011 5012 return; 5013 } 5014 } 5015 5016 if (!isInTouchMode()) { 5017 // We couldn't find matching data -- try to use the same position 5018 newPos = getSelectedItemPosition(); 5019 5020 // Pin position to the available range 5021 if (newPos >= count) { 5022 newPos = count - 1; 5023 } 5024 if (newPos < 0) { 5025 newPos = 0; 5026 } 5027 5028 // Make sure we select something selectable -- first look down 5029 selectablePos = lookForSelectablePosition(newPos, true); 5030 5031 if (selectablePos >= 0) { 5032 setNextSelectedPositionInt(selectablePos); 5033 return; 5034 } else { 5035 // Looking down didn't work -- try looking up 5036 selectablePos = lookForSelectablePosition(newPos, false); 5037 if (selectablePos >= 0) { 5038 setNextSelectedPositionInt(selectablePos); 5039 return; 5040 } 5041 } 5042 } else { 5043 5044 // We already know where we want to resurrect the selection 5045 if (mResurrectToPosition >= 0) { 5046 return; 5047 } 5048 } 5049 5050 } 5051 5052 // Nothing is selected. Give up and reset everything. 5053 mLayoutMode = mStackFromBottom ? LAYOUT_FORCE_BOTTOM : LAYOUT_FORCE_TOP; 5054 mSelectedPosition = INVALID_POSITION; 5055 mSelectedRowId = INVALID_ROW_ID; 5056 mNextSelectedPosition = INVALID_POSITION; 5057 mNextSelectedRowId = INVALID_ROW_ID; 5058 mNeedSync = false; 5059 mSelectorPosition = INVALID_POSITION; 5060 checkSelectionChanged(); 5061 } 5062 5063 @Override 5064 protected void onDisplayHint(int hint) { 5065 super.onDisplayHint(hint); 5066 switch (hint) { 5067 case INVISIBLE: 5068 if (mPopup != null && mPopup.isShowing()) { 5069 dismissPopup(); 5070 } 5071 break; 5072 case VISIBLE: 5073 if (mFiltered && mPopup != null && !mPopup.isShowing()) { 5074 showPopup(); 5075 } 5076 break; 5077 } 5078 mPopupHidden = hint == INVISIBLE; 5079 } 5080 5081 /** 5082 * Removes the filter window 5083 */ 5084 private void dismissPopup() { 5085 if (mPopup != null) { 5086 mPopup.dismiss(); 5087 } 5088 } 5089 5090 /** 5091 * Shows the filter window 5092 */ 5093 private void showPopup() { 5094 // Make sure we have a window before showing the popup 5095 if (getWindowVisibility() == View.VISIBLE) { 5096 createTextFilter(true); 5097 positionPopup(); 5098 // Make sure we get focus if we are showing the popup 5099 checkFocus(); 5100 } 5101 } 5102 5103 private void positionPopup() { 5104 int screenHeight = getResources().getDisplayMetrics().heightPixels; 5105 final int[] xy = new int[2]; 5106 getLocationOnScreen(xy); 5107 // TODO: The 20 below should come from the theme 5108 // TODO: And the gravity should be defined in the theme as well 5109 final int bottomGap = screenHeight - xy[1] - getHeight() + (int) (mDensityScale * 20); 5110 if (!mPopup.isShowing()) { 5111 mPopup.showAtLocation(this, Gravity.BOTTOM | Gravity.CENTER_HORIZONTAL, 5112 xy[0], bottomGap); 5113 } else { 5114 mPopup.update(xy[0], bottomGap, -1, -1); 5115 } 5116 } 5117 5118 /** 5119 * What is the distance between the source and destination rectangles given the direction of 5120 * focus navigation between them? The direction basically helps figure out more quickly what is 5121 * self evident by the relationship between the rects... 5122 * 5123 * @param source the source rectangle 5124 * @param dest the destination rectangle 5125 * @param direction the direction 5126 * @return the distance between the rectangles 5127 */ 5128 static int getDistance(Rect source, Rect dest, int direction) { 5129 int sX, sY; // source x, y 5130 int dX, dY; // dest x, y 5131 switch (direction) { 5132 case View.FOCUS_RIGHT: 5133 sX = source.right; 5134 sY = source.top + source.height() / 2; 5135 dX = dest.left; 5136 dY = dest.top + dest.height() / 2; 5137 break; 5138 case View.FOCUS_DOWN: 5139 sX = source.left + source.width() / 2; 5140 sY = source.bottom; 5141 dX = dest.left + dest.width() / 2; 5142 dY = dest.top; 5143 break; 5144 case View.FOCUS_LEFT: 5145 sX = source.left; 5146 sY = source.top + source.height() / 2; 5147 dX = dest.right; 5148 dY = dest.top + dest.height() / 2; 5149 break; 5150 case View.FOCUS_UP: 5151 sX = source.left + source.width() / 2; 5152 sY = source.top; 5153 dX = dest.left + dest.width() / 2; 5154 dY = dest.bottom; 5155 break; 5156 case View.FOCUS_FORWARD: 5157 case View.FOCUS_BACKWARD: 5158 sX = source.right + source.width() / 2; 5159 sY = source.top + source.height() / 2; 5160 dX = dest.left + dest.width() / 2; 5161 dY = dest.top + dest.height() / 2; 5162 break; 5163 default: 5164 throw new IllegalArgumentException("direction must be one of " 5165 + "{FOCUS_UP, FOCUS_DOWN, FOCUS_LEFT, FOCUS_RIGHT, " 5166 + "FOCUS_FORWARD, FOCUS_BACKWARD}."); 5167 } 5168 int deltaX = dX - sX; 5169 int deltaY = dY - sY; 5170 return deltaY * deltaY + deltaX * deltaX; 5171 } 5172 5173 @Override 5174 protected boolean isInFilterMode() { 5175 return mFiltered; 5176 } 5177 5178 /** 5179 * Sends a key to the text filter window 5180 * 5181 * @param keyCode The keycode for the event 5182 * @param event The actual key event 5183 * 5184 * @return True if the text filter handled the event, false otherwise. 5185 */ 5186 boolean sendToTextFilter(int keyCode, int count, KeyEvent event) { 5187 if (!acceptFilter()) { 5188 return false; 5189 } 5190 5191 boolean handled = false; 5192 boolean okToSend = true; 5193 switch (keyCode) { 5194 case KeyEvent.KEYCODE_DPAD_UP: 5195 case KeyEvent.KEYCODE_DPAD_DOWN: 5196 case KeyEvent.KEYCODE_DPAD_LEFT: 5197 case KeyEvent.KEYCODE_DPAD_RIGHT: 5198 case KeyEvent.KEYCODE_DPAD_CENTER: 5199 case KeyEvent.KEYCODE_ENTER: 5200 okToSend = false; 5201 break; 5202 case KeyEvent.KEYCODE_BACK: 5203 if (mFiltered && mPopup != null && mPopup.isShowing()) { 5204 if (event.getAction() == KeyEvent.ACTION_DOWN 5205 && event.getRepeatCount() == 0) { 5206 KeyEvent.DispatcherState state = getKeyDispatcherState(); 5207 if (state != null) { 5208 state.startTracking(event, this); 5209 } 5210 handled = true; 5211 } else if (event.getAction() == KeyEvent.ACTION_UP 5212 && event.isTracking() && !event.isCanceled()) { 5213 handled = true; 5214 mTextFilter.setText(""); 5215 } 5216 } 5217 okToSend = false; 5218 break; 5219 case KeyEvent.KEYCODE_SPACE: 5220 // Only send spaces once we are filtered 5221 okToSend = mFiltered; 5222 break; 5223 } 5224 5225 if (okToSend) { 5226 createTextFilter(true); 5227 5228 KeyEvent forwardEvent = event; 5229 if (forwardEvent.getRepeatCount() > 0) { 5230 forwardEvent = KeyEvent.changeTimeRepeat(event, event.getEventTime(), 0); 5231 } 5232 5233 int action = event.getAction(); 5234 switch (action) { 5235 case KeyEvent.ACTION_DOWN: 5236 handled = mTextFilter.onKeyDown(keyCode, forwardEvent); 5237 break; 5238 5239 case KeyEvent.ACTION_UP: 5240 handled = mTextFilter.onKeyUp(keyCode, forwardEvent); 5241 break; 5242 5243 case KeyEvent.ACTION_MULTIPLE: 5244 handled = mTextFilter.onKeyMultiple(keyCode, count, event); 5245 break; 5246 } 5247 } 5248 return handled; 5249 } 5250 5251 /** 5252 * Return an InputConnection for editing of the filter text. 5253 */ 5254 @Override 5255 public InputConnection onCreateInputConnection(EditorInfo outAttrs) { 5256 if (isTextFilterEnabled()) { 5257 // XXX we need to have the text filter created, so we can get an 5258 // InputConnection to proxy to. Unfortunately this means we pretty 5259 // much need to make it as soon as a list view gets focus. 5260 createTextFilter(false); 5261 if (mPublicInputConnection == null) { 5262 mDefInputConnection = new BaseInputConnection(this, false); 5263 mPublicInputConnection = new InputConnectionWrapper( 5264 mTextFilter.onCreateInputConnection(outAttrs), true) { 5265 @Override 5266 public boolean reportFullscreenMode(boolean enabled) { 5267 // Use our own input connection, since it is 5268 // the "real" one the IME is talking with. 5269 return mDefInputConnection.reportFullscreenMode(enabled); 5270 } 5271 5272 @Override 5273 public boolean performEditorAction(int editorAction) { 5274 // The editor is off in its own window; we need to be 5275 // the one that does this. 5276 if (editorAction == EditorInfo.IME_ACTION_DONE) { 5277 InputMethodManager imm = (InputMethodManager) 5278 getContext().getSystemService( 5279 Context.INPUT_METHOD_SERVICE); 5280 if (imm != null) { 5281 imm.hideSoftInputFromWindow(getWindowToken(), 0); 5282 } 5283 return true; 5284 } 5285 return false; 5286 } 5287 5288 @Override 5289 public boolean sendKeyEvent(KeyEvent event) { 5290 // Use our own input connection, since the filter 5291 // text view may not be shown in a window so has 5292 // no ViewAncestor to dispatch events with. 5293 return mDefInputConnection.sendKeyEvent(event); 5294 } 5295 }; 5296 } 5297 outAttrs.inputType = EditorInfo.TYPE_CLASS_TEXT 5298 | EditorInfo.TYPE_TEXT_VARIATION_FILTER; 5299 outAttrs.imeOptions = EditorInfo.IME_ACTION_DONE; 5300 return mPublicInputConnection; 5301 } 5302 return null; 5303 } 5304 5305 /** 5306 * For filtering we proxy an input connection to an internal text editor, 5307 * and this allows the proxying to happen. 5308 */ 5309 @Override 5310 public boolean checkInputConnectionProxy(View view) { 5311 return view == mTextFilter; 5312 } 5313 5314 /** 5315 * Creates the window for the text filter and populates it with an EditText field; 5316 * 5317 * @param animateEntrance true if the window should appear with an animation 5318 */ 5319 private void createTextFilter(boolean animateEntrance) { 5320 if (mPopup == null) { 5321 Context c = getContext(); 5322 PopupWindow p = new PopupWindow(c); 5323 LayoutInflater layoutInflater = (LayoutInflater) 5324 c.getSystemService(Context.LAYOUT_INFLATER_SERVICE); 5325 mTextFilter = (EditText) layoutInflater.inflate( 5326 com.android.internal.R.layout.typing_filter, null); 5327 // For some reason setting this as the "real" input type changes 5328 // the text view in some way that it doesn't work, and I don't 5329 // want to figure out why this is. 5330 mTextFilter.setRawInputType(EditorInfo.TYPE_CLASS_TEXT 5331 | EditorInfo.TYPE_TEXT_VARIATION_FILTER); 5332 mTextFilter.setImeOptions(EditorInfo.IME_FLAG_NO_EXTRACT_UI); 5333 mTextFilter.addTextChangedListener(this); 5334 p.setFocusable(false); 5335 p.setTouchable(false); 5336 p.setInputMethodMode(PopupWindow.INPUT_METHOD_NOT_NEEDED); 5337 p.setContentView(mTextFilter); 5338 p.setWidth(LayoutParams.WRAP_CONTENT); 5339 p.setHeight(LayoutParams.WRAP_CONTENT); 5340 p.setBackgroundDrawable(null); 5341 mPopup = p; 5342 getViewTreeObserver().addOnGlobalLayoutListener(this); 5343 mGlobalLayoutListenerAddedFilter = true; 5344 } 5345 if (animateEntrance) { 5346 mPopup.setAnimationStyle(com.android.internal.R.style.Animation_TypingFilter); 5347 } else { 5348 mPopup.setAnimationStyle(com.android.internal.R.style.Animation_TypingFilterRestore); 5349 } 5350 } 5351 5352 /** 5353 * Clear the text filter. 5354 */ 5355 public void clearTextFilter() { 5356 if (mFiltered) { 5357 mTextFilter.setText(""); 5358 mFiltered = false; 5359 if (mPopup != null && mPopup.isShowing()) { 5360 dismissPopup(); 5361 } 5362 } 5363 } 5364 5365 /** 5366 * Returns if the ListView currently has a text filter. 5367 */ 5368 public boolean hasTextFilter() { 5369 return mFiltered; 5370 } 5371 5372 public void onGlobalLayout() { 5373 if (isShown()) { 5374 // Show the popup if we are filtered 5375 if (mFiltered && mPopup != null && !mPopup.isShowing() && !mPopupHidden) { 5376 showPopup(); 5377 } 5378 } else { 5379 // Hide the popup when we are no longer visible 5380 if (mPopup != null && mPopup.isShowing()) { 5381 dismissPopup(); 5382 } 5383 } 5384 5385 } 5386 5387 /** 5388 * For our text watcher that is associated with the text filter. Does 5389 * nothing. 5390 */ 5391 public void beforeTextChanged(CharSequence s, int start, int count, int after) { 5392 } 5393 5394 /** 5395 * For our text watcher that is associated with the text filter. Performs 5396 * the actual filtering as the text changes, and takes care of hiding and 5397 * showing the popup displaying the currently entered filter text. 5398 */ 5399 public void onTextChanged(CharSequence s, int start, int before, int count) { 5400 if (mPopup != null && isTextFilterEnabled()) { 5401 int length = s.length(); 5402 boolean showing = mPopup.isShowing(); 5403 if (!showing && length > 0) { 5404 // Show the filter popup if necessary 5405 showPopup(); 5406 mFiltered = true; 5407 } else if (showing && length == 0) { 5408 // Remove the filter popup if the user has cleared all text 5409 dismissPopup(); 5410 mFiltered = false; 5411 } 5412 if (mAdapter instanceof Filterable) { 5413 Filter f = ((Filterable) mAdapter).getFilter(); 5414 // Filter should not be null when we reach this part 5415 if (f != null) { 5416 f.filter(s, this); 5417 } else { 5418 throw new IllegalStateException("You cannot call onTextChanged with a non " 5419 + "filterable adapter"); 5420 } 5421 } 5422 } 5423 } 5424 5425 /** 5426 * For our text watcher that is associated with the text filter. Does 5427 * nothing. 5428 */ 5429 public void afterTextChanged(Editable s) { 5430 } 5431 5432 public void onFilterComplete(int count) { 5433 if (mSelectedPosition < 0 && count > 0) { 5434 mResurrectToPosition = INVALID_POSITION; 5435 resurrectSelection(); 5436 } 5437 } 5438 5439 @Override 5440 protected ViewGroup.LayoutParams generateDefaultLayoutParams() { 5441 return new AbsListView.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, 5442 ViewGroup.LayoutParams.WRAP_CONTENT, 0); 5443 } 5444 5445 @Override 5446 protected ViewGroup.LayoutParams generateLayoutParams(ViewGroup.LayoutParams p) { 5447 return new LayoutParams(p); 5448 } 5449 5450 @Override 5451 public LayoutParams generateLayoutParams(AttributeSet attrs) { 5452 return new AbsListView.LayoutParams(getContext(), attrs); 5453 } 5454 5455 @Override 5456 protected boolean checkLayoutParams(ViewGroup.LayoutParams p) { 5457 return p instanceof AbsListView.LayoutParams; 5458 } 5459 5460 /** 5461 * Puts the list or grid into transcript mode. In this mode the list or grid will always scroll 5462 * to the bottom to show new items. 5463 * 5464 * @param mode the transcript mode to set 5465 * 5466 * @see #TRANSCRIPT_MODE_DISABLED 5467 * @see #TRANSCRIPT_MODE_NORMAL 5468 * @see #TRANSCRIPT_MODE_ALWAYS_SCROLL 5469 */ 5470 public void setTranscriptMode(int mode) { 5471 mTranscriptMode = mode; 5472 } 5473 5474 /** 5475 * Returns the current transcript mode. 5476 * 5477 * @return {@link #TRANSCRIPT_MODE_DISABLED}, {@link #TRANSCRIPT_MODE_NORMAL} or 5478 * {@link #TRANSCRIPT_MODE_ALWAYS_SCROLL} 5479 */ 5480 public int getTranscriptMode() { 5481 return mTranscriptMode; 5482 } 5483 5484 @Override 5485 public int getSolidColor() { 5486 return mCacheColorHint; 5487 } 5488 5489 /** 5490 * When set to a non-zero value, the cache color hint indicates that this list is always drawn 5491 * on top of a solid, single-color, opaque background. 5492 * 5493 * Zero means that what's behind this object is translucent (non solid) or is not made of a 5494 * single color. This hint will not affect any existing background drawable set on this view ( 5495 * typically set via {@link #setBackgroundDrawable(Drawable)}). 5496 * 5497 * @param color The background color 5498 */ 5499 public void setCacheColorHint(int color) { 5500 if (color != mCacheColorHint) { 5501 mCacheColorHint = color; 5502 int count = getChildCount(); 5503 for (int i = 0; i < count; i++) { 5504 getChildAt(i).setDrawingCacheBackgroundColor(color); 5505 } 5506 mRecycler.setCacheColorHint(color); 5507 } 5508 } 5509 5510 /** 5511 * When set to a non-zero value, the cache color hint indicates that this list is always drawn 5512 * on top of a solid, single-color, opaque background 5513 * 5514 * @return The cache color hint 5515 */ 5516 @ViewDebug.ExportedProperty(category = "drawing") 5517 public int getCacheColorHint() { 5518 return mCacheColorHint; 5519 } 5520 5521 /** 5522 * Move all views (excluding headers and footers) held by this AbsListView into the supplied 5523 * List. This includes views displayed on the screen as well as views stored in AbsListView's 5524 * internal view recycler. 5525 * 5526 * @param views A list into which to put the reclaimed views 5527 */ 5528 public void reclaimViews(List<View> views) { 5529 int childCount = getChildCount(); 5530 RecyclerListener listener = mRecycler.mRecyclerListener; 5531 5532 // Reclaim views on screen 5533 for (int i = 0; i < childCount; i++) { 5534 View child = getChildAt(i); 5535 AbsListView.LayoutParams lp = (AbsListView.LayoutParams) child.getLayoutParams(); 5536 // Don't reclaim header or footer views, or views that should be ignored 5537 if (lp != null && mRecycler.shouldRecycleViewType(lp.viewType)) { 5538 views.add(child); 5539 if (listener != null) { 5540 // Pretend they went through the scrap heap 5541 listener.onMovedToScrapHeap(child); 5542 } 5543 } 5544 } 5545 mRecycler.reclaimScrapViews(views); 5546 removeAllViewsInLayout(); 5547 } 5548 5549 /** 5550 * @hide 5551 */ 5552 @Override 5553 protected boolean onConsistencyCheck(int consistency) { 5554 boolean result = super.onConsistencyCheck(consistency); 5555 5556 final boolean checkLayout = (consistency & ViewDebug.CONSISTENCY_LAYOUT) != 0; 5557 5558 if (checkLayout) { 5559 // The active recycler must be empty 5560 final View[] activeViews = mRecycler.mActiveViews; 5561 int count = activeViews.length; 5562 for (int i = 0; i < count; i++) { 5563 if (activeViews[i] != null) { 5564 result = false; 5565 Log.d(ViewDebug.CONSISTENCY_LOG_TAG, 5566 "AbsListView " + this + " has a view in its active recycler: " + 5567 activeViews[i]); 5568 } 5569 } 5570 5571 // All views in the recycler must NOT be on screen and must NOT have a parent 5572 final ArrayList<View> scrap = mRecycler.mCurrentScrap; 5573 if (!checkScrap(scrap)) result = false; 5574 final ArrayList<View>[] scraps = mRecycler.mScrapViews; 5575 count = scraps.length; 5576 for (int i = 0; i < count; i++) { 5577 if (!checkScrap(scraps[i])) result = false; 5578 } 5579 } 5580 5581 return result; 5582 } 5583 5584 private boolean checkScrap(ArrayList<View> scrap) { 5585 if (scrap == null) return true; 5586 boolean result = true; 5587 5588 final int count = scrap.size(); 5589 for (int i = 0; i < count; i++) { 5590 final View view = scrap.get(i); 5591 if (view.getParent() != null) { 5592 result = false; 5593 Log.d(ViewDebug.CONSISTENCY_LOG_TAG, "AbsListView " + this + 5594 " has a view in its scrap heap still attached to a parent: " + view); 5595 } 5596 if (indexOfChild(view) >= 0) { 5597 result = false; 5598 Log.d(ViewDebug.CONSISTENCY_LOG_TAG, "AbsListView " + this + 5599 " has a view in its scrap heap that is also a direct child: " + view); 5600 } 5601 } 5602 5603 return result; 5604 } 5605 5606 private void finishGlows() { 5607 if (mEdgeGlowTop != null) { 5608 mEdgeGlowTop.finish(); 5609 mEdgeGlowBottom.finish(); 5610 } 5611 } 5612 5613 /** 5614 * Sets up this AbsListView to use a remote views adapter which connects to a RemoteViewsService 5615 * through the specified intent. 5616 * @param intent the intent used to identify the RemoteViewsService for the adapter to connect to. 5617 */ 5618 public void setRemoteViewsAdapter(Intent intent) { 5619 // Ensure that we don't already have a RemoteViewsAdapter that is bound to an existing 5620 // service handling the specified intent. 5621 if (mRemoteAdapter != null) { 5622 Intent.FilterComparison fcNew = new Intent.FilterComparison(intent); 5623 Intent.FilterComparison fcOld = new Intent.FilterComparison( 5624 mRemoteAdapter.getRemoteViewsServiceIntent()); 5625 if (fcNew.equals(fcOld)) { 5626 return; 5627 } 5628 } 5629 mDeferNotifyDataSetChanged = false; 5630 // Otherwise, create a new RemoteViewsAdapter for binding 5631 mRemoteAdapter = new RemoteViewsAdapter(getContext(), intent, this); 5632 } 5633 5634 /** 5635 * This defers a notifyDataSetChanged on the pending RemoteViewsAdapter if it has not 5636 * connected yet. 5637 */ 5638 public void deferNotifyDataSetChanged() { 5639 mDeferNotifyDataSetChanged = true; 5640 } 5641 5642 /** 5643 * Called back when the adapter connects to the RemoteViewsService. 5644 */ 5645 public boolean onRemoteAdapterConnected() { 5646 if (mRemoteAdapter != mAdapter) { 5647 setAdapter(mRemoteAdapter); 5648 if (mDeferNotifyDataSetChanged) { 5649 mRemoteAdapter.notifyDataSetChanged(); 5650 mDeferNotifyDataSetChanged = false; 5651 } 5652 return false; 5653 } else if (mRemoteAdapter != null) { 5654 mRemoteAdapter.superNotifyDataSetChanged(); 5655 return true; 5656 } 5657 return false; 5658 } 5659 5660 /** 5661 * Called back when the adapter disconnects from the RemoteViewsService. 5662 */ 5663 public void onRemoteAdapterDisconnected() { 5664 // If the remote adapter disconnects, we keep it around 5665 // since the currently displayed items are still cached. 5666 // Further, we want the service to eventually reconnect 5667 // when necessary, as triggered by this view requesting 5668 // items from the Adapter. 5669 } 5670 5671 /** 5672 * Hints the RemoteViewsAdapter, if it exists, about which views are currently 5673 * being displayed by the AbsListView. 5674 */ 5675 void setVisibleRangeHint(int start, int end) { 5676 if (mRemoteAdapter != null) { 5677 mRemoteAdapter.setVisibleRangeHint(start, end); 5678 } 5679 } 5680 5681 /** 5682 * Sets the recycler listener to be notified whenever a View is set aside in 5683 * the recycler for later reuse. This listener can be used to free resources 5684 * associated to the View. 5685 * 5686 * @param listener The recycler listener to be notified of views set aside 5687 * in the recycler. 5688 * 5689 * @see android.widget.AbsListView.RecycleBin 5690 * @see android.widget.AbsListView.RecyclerListener 5691 */ 5692 public void setRecyclerListener(RecyclerListener listener) { 5693 mRecycler.mRecyclerListener = listener; 5694 } 5695 5696 class AdapterDataSetObserver extends AdapterView<ListAdapter>.AdapterDataSetObserver { 5697 @Override 5698 public void onChanged() { 5699 super.onChanged(); 5700 if (mFastScroller != null) { 5701 mFastScroller.onSectionsChanged(); 5702 } 5703 } 5704 5705 @Override 5706 public void onInvalidated() { 5707 super.onInvalidated(); 5708 if (mFastScroller != null) { 5709 mFastScroller.onSectionsChanged(); 5710 } 5711 } 5712 } 5713 5714 /** 5715 * A MultiChoiceModeListener receives events for {@link AbsListView#CHOICE_MODE_MULTIPLE_MODAL}. 5716 * It acts as the {@link ActionMode.Callback} for the selection mode and also receives 5717 * {@link #onItemCheckedStateChanged(ActionMode, int, long, boolean)} events when the user 5718 * selects and deselects list items. 5719 */ 5720 public interface MultiChoiceModeListener extends ActionMode.Callback { 5721 /** 5722 * Called when an item is checked or unchecked during selection mode. 5723 * 5724 * @param mode The {@link ActionMode} providing the selection mode 5725 * @param position Adapter position of the item that was checked or unchecked 5726 * @param id Adapter ID of the item that was checked or unchecked 5727 * @param checked <code>true</code> if the item is now checked, <code>false</code> 5728 * if the item is now unchecked. 5729 */ 5730 public void onItemCheckedStateChanged(ActionMode mode, 5731 int position, long id, boolean checked); 5732 } 5733 5734 class MultiChoiceModeWrapper implements MultiChoiceModeListener { 5735 private MultiChoiceModeListener mWrapped; 5736 5737 public void setWrapped(MultiChoiceModeListener wrapped) { 5738 mWrapped = wrapped; 5739 } 5740 5741 public boolean onCreateActionMode(ActionMode mode, Menu menu) { 5742 if (mWrapped.onCreateActionMode(mode, menu)) { 5743 // Initialize checked graphic state? 5744 setLongClickable(false); 5745 return true; 5746 } 5747 return false; 5748 } 5749 5750 public boolean onPrepareActionMode(ActionMode mode, Menu menu) { 5751 return mWrapped.onPrepareActionMode(mode, menu); 5752 } 5753 5754 public boolean onActionItemClicked(ActionMode mode, MenuItem item) { 5755 return mWrapped.onActionItemClicked(mode, item); 5756 } 5757 5758 public void onDestroyActionMode(ActionMode mode) { 5759 mWrapped.onDestroyActionMode(mode); 5760 mChoiceActionMode = null; 5761 5762 // Ending selection mode means deselecting everything. 5763 clearChoices(); 5764 5765 mDataChanged = true; 5766 rememberSyncState(); 5767 requestLayout(); 5768 5769 setLongClickable(true); 5770 } 5771 5772 public void onItemCheckedStateChanged(ActionMode mode, 5773 int position, long id, boolean checked) { 5774 mWrapped.onItemCheckedStateChanged(mode, position, id, checked); 5775 5776 // If there are no items selected we no longer need the selection mode. 5777 if (getCheckedItemCount() == 0) { 5778 mode.finish(); 5779 } 5780 } 5781 } 5782 5783 /** 5784 * AbsListView extends LayoutParams to provide a place to hold the view type. 5785 */ 5786 public static class LayoutParams extends ViewGroup.LayoutParams { 5787 /** 5788 * View type for this view, as returned by 5789 * {@link android.widget.Adapter#getItemViewType(int) } 5790 */ 5791 @ViewDebug.ExportedProperty(category = "list", mapping = { 5792 @ViewDebug.IntToString(from = ITEM_VIEW_TYPE_IGNORE, to = "ITEM_VIEW_TYPE_IGNORE"), 5793 @ViewDebug.IntToString(from = ITEM_VIEW_TYPE_HEADER_OR_FOOTER, to = "ITEM_VIEW_TYPE_HEADER_OR_FOOTER") 5794 }) 5795 int viewType; 5796 5797 /** 5798 * When this boolean is set, the view has been added to the AbsListView 5799 * at least once. It is used to know whether headers/footers have already 5800 * been added to the list view and whether they should be treated as 5801 * recycled views or not. 5802 */ 5803 @ViewDebug.ExportedProperty(category = "list") 5804 boolean recycledHeaderFooter; 5805 5806 /** 5807 * When an AbsListView is measured with an AT_MOST measure spec, it needs 5808 * to obtain children views to measure itself. When doing so, the children 5809 * are not attached to the window, but put in the recycler which assumes 5810 * they've been attached before. Setting this flag will force the reused 5811 * view to be attached to the window rather than just attached to the 5812 * parent. 5813 */ 5814 @ViewDebug.ExportedProperty(category = "list") 5815 boolean forceAdd; 5816 5817 /** 5818 * The position the view was removed from when pulled out of the 5819 * scrap heap. 5820 * @hide 5821 */ 5822 int scrappedFromPosition; 5823 5824 /** 5825 * The ID the view represents 5826 */ 5827 long itemId = -1; 5828 5829 public LayoutParams(Context c, AttributeSet attrs) { 5830 super(c, attrs); 5831 } 5832 5833 public LayoutParams(int w, int h) { 5834 super(w, h); 5835 } 5836 5837 public LayoutParams(int w, int h, int viewType) { 5838 super(w, h); 5839 this.viewType = viewType; 5840 } 5841 5842 public LayoutParams(ViewGroup.LayoutParams source) { 5843 super(source); 5844 } 5845 } 5846 5847 /** 5848 * A RecyclerListener is used to receive a notification whenever a View is placed 5849 * inside the RecycleBin's scrap heap. This listener is used to free resources 5850 * associated to Views placed in the RecycleBin. 5851 * 5852 * @see android.widget.AbsListView.RecycleBin 5853 * @see android.widget.AbsListView#setRecyclerListener(android.widget.AbsListView.RecyclerListener) 5854 */ 5855 public static interface RecyclerListener { 5856 /** 5857 * Indicates that the specified View was moved into the recycler's scrap heap. 5858 * The view is not displayed on screen any more and any expensive resource 5859 * associated with the view should be discarded. 5860 * 5861 * @param view 5862 */ 5863 void onMovedToScrapHeap(View view); 5864 } 5865 5866 /** 5867 * The RecycleBin facilitates reuse of views across layouts. The RecycleBin has two levels of 5868 * storage: ActiveViews and ScrapViews. ActiveViews are those views which were onscreen at the 5869 * start of a layout. By construction, they are displaying current information. At the end of 5870 * layout, all views in ActiveViews are demoted to ScrapViews. ScrapViews are old views that 5871 * could potentially be used by the adapter to avoid allocating views unnecessarily. 5872 * 5873 * @see android.widget.AbsListView#setRecyclerListener(android.widget.AbsListView.RecyclerListener) 5874 * @see android.widget.AbsListView.RecyclerListener 5875 */ 5876 class RecycleBin { 5877 private RecyclerListener mRecyclerListener; 5878 5879 /** 5880 * The position of the first view stored in mActiveViews. 5881 */ 5882 private int mFirstActivePosition; 5883 5884 /** 5885 * Views that were on screen at the start of layout. This array is populated at the start of 5886 * layout, and at the end of layout all view in mActiveViews are moved to mScrapViews. 5887 * Views in mActiveViews represent a contiguous range of Views, with position of the first 5888 * view store in mFirstActivePosition. 5889 */ 5890 private View[] mActiveViews = new View[0]; 5891 5892 /** 5893 * Unsorted views that can be used by the adapter as a convert view. 5894 */ 5895 private ArrayList<View>[] mScrapViews; 5896 5897 private int mViewTypeCount; 5898 5899 private ArrayList<View> mCurrentScrap; 5900 5901 private ArrayList<View> mSkippedScrap; 5902 5903 private SparseArray<View> mTransientStateViews; 5904 5905 public void setViewTypeCount(int viewTypeCount) { 5906 if (viewTypeCount < 1) { 5907 throw new IllegalArgumentException("Can't have a viewTypeCount < 1"); 5908 } 5909 //noinspection unchecked 5910 ArrayList<View>[] scrapViews = new ArrayList[viewTypeCount]; 5911 for (int i = 0; i < viewTypeCount; i++) { 5912 scrapViews[i] = new ArrayList<View>(); 5913 } 5914 mViewTypeCount = viewTypeCount; 5915 mCurrentScrap = scrapViews[0]; 5916 mScrapViews = scrapViews; 5917 } 5918 5919 public void markChildrenDirty() { 5920 if (mViewTypeCount == 1) { 5921 final ArrayList<View> scrap = mCurrentScrap; 5922 final int scrapCount = scrap.size(); 5923 for (int i = 0; i < scrapCount; i++) { 5924 scrap.get(i).forceLayout(); 5925 } 5926 } else { 5927 final int typeCount = mViewTypeCount; 5928 for (int i = 0; i < typeCount; i++) { 5929 final ArrayList<View> scrap = mScrapViews[i]; 5930 final int scrapCount = scrap.size(); 5931 for (int j = 0; j < scrapCount; j++) { 5932 scrap.get(j).forceLayout(); 5933 } 5934 } 5935 } 5936 if (mTransientStateViews != null) { 5937 final int count = mTransientStateViews.size(); 5938 for (int i = 0; i < count; i++) { 5939 mTransientStateViews.valueAt(i).forceLayout(); 5940 } 5941 } 5942 } 5943 5944 public boolean shouldRecycleViewType(int viewType) { 5945 return viewType >= 0; 5946 } 5947 5948 /** 5949 * Clears the scrap heap. 5950 */ 5951 void clear() { 5952 if (mViewTypeCount == 1) { 5953 final ArrayList<View> scrap = mCurrentScrap; 5954 final int scrapCount = scrap.size(); 5955 for (int i = 0; i < scrapCount; i++) { 5956 removeDetachedView(scrap.remove(scrapCount - 1 - i), false); 5957 } 5958 } else { 5959 final int typeCount = mViewTypeCount; 5960 for (int i = 0; i < typeCount; i++) { 5961 final ArrayList<View> scrap = mScrapViews[i]; 5962 final int scrapCount = scrap.size(); 5963 for (int j = 0; j < scrapCount; j++) { 5964 removeDetachedView(scrap.remove(scrapCount - 1 - j), false); 5965 } 5966 } 5967 } 5968 if (mTransientStateViews != null) { 5969 mTransientStateViews.clear(); 5970 } 5971 } 5972 5973 /** 5974 * Fill ActiveViews with all of the children of the AbsListView. 5975 * 5976 * @param childCount The minimum number of views mActiveViews should hold 5977 * @param firstActivePosition The position of the first view that will be stored in 5978 * mActiveViews 5979 */ 5980 void fillActiveViews(int childCount, int firstActivePosition) { 5981 if (mActiveViews.length < childCount) { 5982 mActiveViews = new View[childCount]; 5983 } 5984 mFirstActivePosition = firstActivePosition; 5985 5986 final View[] activeViews = mActiveViews; 5987 for (int i = 0; i < childCount; i++) { 5988 View child = getChildAt(i); 5989 AbsListView.LayoutParams lp = (AbsListView.LayoutParams) child.getLayoutParams(); 5990 // Don't put header or footer views into the scrap heap 5991 if (lp != null && lp.viewType != ITEM_VIEW_TYPE_HEADER_OR_FOOTER) { 5992 // Note: We do place AdapterView.ITEM_VIEW_TYPE_IGNORE in active views. 5993 // However, we will NOT place them into scrap views. 5994 activeViews[i] = child; 5995 } 5996 } 5997 } 5998 5999 /** 6000 * Get the view corresponding to the specified position. The view will be removed from 6001 * mActiveViews if it is found. 6002 * 6003 * @param position The position to look up in mActiveViews 6004 * @return The view if it is found, null otherwise 6005 */ 6006 View getActiveView(int position) { 6007 int index = position - mFirstActivePosition; 6008 final View[] activeViews = mActiveViews; 6009 if (index >=0 && index < activeViews.length) { 6010 final View match = activeViews[index]; 6011 activeViews[index] = null; 6012 return match; 6013 } 6014 return null; 6015 } 6016 6017 View getTransientStateView(int position) { 6018 if (mTransientStateViews == null) { 6019 return null; 6020 } 6021 final int index = mTransientStateViews.indexOfKey(position); 6022 if (index < 0) { 6023 return null; 6024 } 6025 final View result = mTransientStateViews.valueAt(index); 6026 mTransientStateViews.removeAt(index); 6027 return result; 6028 } 6029 6030 /** 6031 * Dump any currently saved views with transient state. 6032 */ 6033 void clearTransientStateViews() { 6034 if (mTransientStateViews != null) { 6035 mTransientStateViews.clear(); 6036 } 6037 } 6038 6039 /** 6040 * @return A view from the ScrapViews collection. These are unordered. 6041 */ 6042 View getScrapView(int position) { 6043 if (mViewTypeCount == 1) { 6044 return retrieveFromScrap(mCurrentScrap, position); 6045 } else { 6046 int whichScrap = mAdapter.getItemViewType(position); 6047 if (whichScrap >= 0 && whichScrap < mScrapViews.length) { 6048 return retrieveFromScrap(mScrapViews[whichScrap], position); 6049 } 6050 } 6051 return null; 6052 } 6053 6054 /** 6055 * Put a view into the ScrapViews list. These views are unordered. 6056 * 6057 * @param scrap The view to add 6058 */ 6059 void addScrapView(View scrap, int position) { 6060 AbsListView.LayoutParams lp = (AbsListView.LayoutParams) scrap.getLayoutParams(); 6061 if (lp == null) { 6062 return; 6063 } 6064 6065 lp.scrappedFromPosition = position; 6066 6067 // Don't put header or footer views or views that should be ignored 6068 // into the scrap heap 6069 int viewType = lp.viewType; 6070 final boolean scrapHasTransientState = scrap.hasTransientState(); 6071 if (!shouldRecycleViewType(viewType) || scrapHasTransientState) { 6072 if (viewType != ITEM_VIEW_TYPE_HEADER_OR_FOOTER || scrapHasTransientState) { 6073 if (mSkippedScrap == null) { 6074 mSkippedScrap = new ArrayList<View>(); 6075 } 6076 mSkippedScrap.add(scrap); 6077 } 6078 if (scrapHasTransientState) { 6079 if (mTransientStateViews == null) { 6080 mTransientStateViews = new SparseArray<View>(); 6081 } 6082 mTransientStateViews.put(position, scrap); 6083 } 6084 return; 6085 } 6086 6087 scrap.dispatchStartTemporaryDetach(); 6088 if (mViewTypeCount == 1) { 6089 mCurrentScrap.add(scrap); 6090 } else { 6091 mScrapViews[viewType].add(scrap); 6092 } 6093 6094 if (mRecyclerListener != null) { 6095 mRecyclerListener.onMovedToScrapHeap(scrap); 6096 } 6097 } 6098 6099 /** 6100 * Finish the removal of any views that skipped the scrap heap. 6101 */ 6102 void removeSkippedScrap() { 6103 if (mSkippedScrap == null) { 6104 return; 6105 } 6106 final int count = mSkippedScrap.size(); 6107 for (int i = 0; i < count; i++) { 6108 removeDetachedView(mSkippedScrap.get(i), false); 6109 } 6110 mSkippedScrap.clear(); 6111 } 6112 6113 /** 6114 * Move all views remaining in mActiveViews to mScrapViews. 6115 */ 6116 void scrapActiveViews() { 6117 final View[] activeViews = mActiveViews; 6118 final boolean hasListener = mRecyclerListener != null; 6119 final boolean multipleScraps = mViewTypeCount > 1; 6120 6121 ArrayList<View> scrapViews = mCurrentScrap; 6122 final int count = activeViews.length; 6123 for (int i = count - 1; i >= 0; i--) { 6124 final View victim = activeViews[i]; 6125 if (victim != null) { 6126 final AbsListView.LayoutParams lp 6127 = (AbsListView.LayoutParams) victim.getLayoutParams(); 6128 int whichScrap = lp.viewType; 6129 6130 activeViews[i] = null; 6131 6132 final boolean scrapHasTransientState = victim.hasTransientState(); 6133 if (!shouldRecycleViewType(whichScrap) || scrapHasTransientState) { 6134 // Do not move views that should be ignored 6135 if (whichScrap != ITEM_VIEW_TYPE_HEADER_OR_FOOTER || 6136 scrapHasTransientState) { 6137 removeDetachedView(victim, false); 6138 } 6139 if (scrapHasTransientState) { 6140 if (mTransientStateViews == null) { 6141 mTransientStateViews = new SparseArray<View>(); 6142 } 6143 mTransientStateViews.put(mFirstActivePosition + i, victim); 6144 } 6145 continue; 6146 } 6147 6148 if (multipleScraps) { 6149 scrapViews = mScrapViews[whichScrap]; 6150 } 6151 victim.dispatchStartTemporaryDetach(); 6152 lp.scrappedFromPosition = mFirstActivePosition + i; 6153 scrapViews.add(victim); 6154 6155 if (hasListener) { 6156 mRecyclerListener.onMovedToScrapHeap(victim); 6157 } 6158 6159 if (ViewDebug.TRACE_RECYCLER) { 6160 ViewDebug.trace(victim, 6161 ViewDebug.RecyclerTraceType.MOVE_FROM_ACTIVE_TO_SCRAP_HEAP, 6162 mFirstActivePosition + i, -1); 6163 } 6164 } 6165 } 6166 6167 pruneScrapViews(); 6168 } 6169 6170 /** 6171 * Makes sure that the size of mScrapViews does not exceed the size of mActiveViews. 6172 * (This can happen if an adapter does not recycle its views). 6173 */ 6174 private void pruneScrapViews() { 6175 final int maxViews = mActiveViews.length; 6176 final int viewTypeCount = mViewTypeCount; 6177 final ArrayList<View>[] scrapViews = mScrapViews; 6178 for (int i = 0; i < viewTypeCount; ++i) { 6179 final ArrayList<View> scrapPile = scrapViews[i]; 6180 int size = scrapPile.size(); 6181 final int extras = size - maxViews; 6182 size--; 6183 for (int j = 0; j < extras; j++) { 6184 removeDetachedView(scrapPile.remove(size--), false); 6185 } 6186 } 6187 } 6188 6189 /** 6190 * Puts all views in the scrap heap into the supplied list. 6191 */ 6192 void reclaimScrapViews(List<View> views) { 6193 if (mViewTypeCount == 1) { 6194 views.addAll(mCurrentScrap); 6195 } else { 6196 final int viewTypeCount = mViewTypeCount; 6197 final ArrayList<View>[] scrapViews = mScrapViews; 6198 for (int i = 0; i < viewTypeCount; ++i) { 6199 final ArrayList<View> scrapPile = scrapViews[i]; 6200 views.addAll(scrapPile); 6201 } 6202 } 6203 } 6204 6205 /** 6206 * Updates the cache color hint of all known views. 6207 * 6208 * @param color The new cache color hint. 6209 */ 6210 void setCacheColorHint(int color) { 6211 if (mViewTypeCount == 1) { 6212 final ArrayList<View> scrap = mCurrentScrap; 6213 final int scrapCount = scrap.size(); 6214 for (int i = 0; i < scrapCount; i++) { 6215 scrap.get(i).setDrawingCacheBackgroundColor(color); 6216 } 6217 } else { 6218 final int typeCount = mViewTypeCount; 6219 for (int i = 0; i < typeCount; i++) { 6220 final ArrayList<View> scrap = mScrapViews[i]; 6221 final int scrapCount = scrap.size(); 6222 for (int j = 0; j < scrapCount; j++) { 6223 scrap.get(j).setDrawingCacheBackgroundColor(color); 6224 } 6225 } 6226 } 6227 // Just in case this is called during a layout pass 6228 final View[] activeViews = mActiveViews; 6229 final int count = activeViews.length; 6230 for (int i = 0; i < count; ++i) { 6231 final View victim = activeViews[i]; 6232 if (victim != null) { 6233 victim.setDrawingCacheBackgroundColor(color); 6234 } 6235 } 6236 } 6237 } 6238 6239 static View retrieveFromScrap(ArrayList<View> scrapViews, int position) { 6240 int size = scrapViews.size(); 6241 if (size > 0) { 6242 // See if we still have a view for this position. 6243 for (int i=0; i<size; i++) { 6244 View view = scrapViews.get(i); 6245 if (((AbsListView.LayoutParams)view.getLayoutParams()) 6246 .scrappedFromPosition == position) { 6247 scrapViews.remove(i); 6248 return view; 6249 } 6250 } 6251 return scrapViews.remove(size - 1); 6252 } else { 6253 return null; 6254 } 6255 } 6256} 6257