AbsListView.java revision 044a46bda5e2f6bc9f700e65d05ed17faae68f11
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.Resources; 24import android.content.res.TypedArray; 25import android.graphics.Canvas; 26import android.graphics.Rect; 27import android.graphics.drawable.Drawable; 28import android.graphics.drawable.TransitionDrawable; 29import android.os.Debug; 30import android.os.Handler; 31import android.os.Parcel; 32import android.os.Parcelable; 33import android.os.StrictMode; 34import android.text.Editable; 35import android.text.TextUtils; 36import android.text.TextWatcher; 37import android.util.AttributeSet; 38import android.util.Log; 39import android.util.LongSparseArray; 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.ViewTreeObserver; 58import android.view.accessibility.AccessibilityEvent; 59import android.view.accessibility.AccessibilityNodeInfo; 60import android.view.inputmethod.BaseInputConnection; 61import android.view.inputmethod.EditorInfo; 62import android.view.inputmethod.InputConnection; 63import android.view.inputmethod.InputConnectionWrapper; 64import android.view.inputmethod.InputMethodManager; 65 66import java.util.ArrayList; 67import java.util.List; 68 69/** 70 * Base class that can be used to implement virtualized lists of items. A list does 71 * not have a spatial definition here. For instance, subclases of this class can 72 * display the content of the list in a grid, in a carousel, as stack, etc. 73 * 74 * @attr ref android.R.styleable#AbsListView_listSelector 75 * @attr ref android.R.styleable#AbsListView_drawSelectorOnTop 76 * @attr ref android.R.styleable#AbsListView_stackFromBottom 77 * @attr ref android.R.styleable#AbsListView_scrollingCache 78 * @attr ref android.R.styleable#AbsListView_textFilterEnabled 79 * @attr ref android.R.styleable#AbsListView_transcriptMode 80 * @attr ref android.R.styleable#AbsListView_cacheColorHint 81 * @attr ref android.R.styleable#AbsListView_fastScrollEnabled 82 * @attr ref android.R.styleable#AbsListView_smoothScrollbar 83 * @attr ref android.R.styleable#AbsListView_choiceMode 84 */ 85public abstract class AbsListView extends AdapterView<ListAdapter> implements TextWatcher, 86 ViewTreeObserver.OnGlobalLayoutListener, Filter.FilterListener, 87 ViewTreeObserver.OnTouchModeChangeListener, 88 RemoteViewsAdapter.RemoteAdapterConnectionCallback { 89 90 /** 91 * Disables the transcript mode. 92 * 93 * @see #setTranscriptMode(int) 94 */ 95 public static final int TRANSCRIPT_MODE_DISABLED = 0; 96 /** 97 * The list will automatically scroll to the bottom when a data set change 98 * notification is received and only if the last item is already visible 99 * on screen. 100 * 101 * @see #setTranscriptMode(int) 102 */ 103 public static final int TRANSCRIPT_MODE_NORMAL = 1; 104 /** 105 * The list will automatically scroll to the bottom, no matter what items 106 * are currently visible. 107 * 108 * @see #setTranscriptMode(int) 109 */ 110 public static final int TRANSCRIPT_MODE_ALWAYS_SCROLL = 2; 111 112 /** 113 * Indicates that we are not in the middle of a touch gesture 114 */ 115 static final int TOUCH_MODE_REST = -1; 116 117 /** 118 * Indicates we just received the touch event and we are waiting to see if the it is a tap or a 119 * scroll gesture. 120 */ 121 static final int TOUCH_MODE_DOWN = 0; 122 123 /** 124 * Indicates the touch has been recognized as a tap and we are now waiting to see if the touch 125 * is a longpress 126 */ 127 static final int TOUCH_MODE_TAP = 1; 128 129 /** 130 * Indicates we have waited for everything we can wait for, but the user's finger is still down 131 */ 132 static final int TOUCH_MODE_DONE_WAITING = 2; 133 134 /** 135 * Indicates the touch gesture is a scroll 136 */ 137 static final int TOUCH_MODE_SCROLL = 3; 138 139 /** 140 * Indicates the view is in the process of being flung 141 */ 142 static final int TOUCH_MODE_FLING = 4; 143 144 /** 145 * Indicates the touch gesture is an overscroll - a scroll beyond the beginning or end. 146 */ 147 static final int TOUCH_MODE_OVERSCROLL = 5; 148 149 /** 150 * Indicates the view is being flung outside of normal content bounds 151 * and will spring back. 152 */ 153 static final int TOUCH_MODE_OVERFLING = 6; 154 155 /** 156 * Regular layout - usually an unsolicited layout from the view system 157 */ 158 static final int LAYOUT_NORMAL = 0; 159 160 /** 161 * Show the first item 162 */ 163 static final int LAYOUT_FORCE_TOP = 1; 164 165 /** 166 * Force the selected item to be on somewhere on the screen 167 */ 168 static final int LAYOUT_SET_SELECTION = 2; 169 170 /** 171 * Show the last item 172 */ 173 static final int LAYOUT_FORCE_BOTTOM = 3; 174 175 /** 176 * Make a mSelectedItem appear in a specific location and build the rest of 177 * the views from there. The top is specified by mSpecificTop. 178 */ 179 static final int LAYOUT_SPECIFIC = 4; 180 181 /** 182 * Layout to sync as a result of a data change. Restore mSyncPosition to have its top 183 * at mSpecificTop 184 */ 185 static final int LAYOUT_SYNC = 5; 186 187 /** 188 * Layout as a result of using the navigation keys 189 */ 190 static final int LAYOUT_MOVE_SELECTION = 6; 191 192 /** 193 * Normal list that does not indicate choices 194 */ 195 public static final int CHOICE_MODE_NONE = 0; 196 197 /** 198 * The list allows up to one choice 199 */ 200 public static final int CHOICE_MODE_SINGLE = 1; 201 202 /** 203 * The list allows multiple choices 204 */ 205 public static final int CHOICE_MODE_MULTIPLE = 2; 206 207 /** 208 * The list allows multiple choices in a modal selection mode 209 */ 210 public static final int CHOICE_MODE_MULTIPLE_MODAL = 3; 211 212 /** 213 * Controls if/how the user may choose/check items in the list 214 */ 215 int mChoiceMode = CHOICE_MODE_NONE; 216 217 /** 218 * Controls CHOICE_MODE_MULTIPLE_MODAL. null when inactive. 219 */ 220 ActionMode mChoiceActionMode; 221 222 /** 223 * Wrapper for the multiple choice mode callback; AbsListView needs to perform 224 * a few extra actions around what application code does. 225 */ 226 MultiChoiceModeWrapper mMultiChoiceModeCallback; 227 228 /** 229 * Running count of how many items are currently checked 230 */ 231 int mCheckedItemCount; 232 233 /** 234 * Running state of which positions are currently checked 235 */ 236 SparseBooleanArray mCheckStates; 237 238 /** 239 * Running state of which IDs are currently checked 240 */ 241 LongSparseArray<Boolean> mCheckedIdStates; 242 243 /** 244 * Controls how the next layout will happen 245 */ 246 int mLayoutMode = LAYOUT_NORMAL; 247 248 /** 249 * Should be used by subclasses to listen to changes in the dataset 250 */ 251 AdapterDataSetObserver mDataSetObserver; 252 253 /** 254 * The adapter containing the data to be displayed by this view 255 */ 256 ListAdapter mAdapter; 257 258 /** 259 * The remote adapter containing the data to be displayed by this view to be set 260 */ 261 private RemoteViewsAdapter mRemoteAdapter; 262 263 /** 264 * Indicates whether the list selector should be drawn on top of the children or behind 265 */ 266 boolean mDrawSelectorOnTop = false; 267 268 /** 269 * The drawable used to draw the selector 270 */ 271 Drawable mSelector; 272 273 /** 274 * The current position of the selector in the list. 275 */ 276 int mSelectorPosition = INVALID_POSITION; 277 278 /** 279 * Defines the selector's location and dimension at drawing time 280 */ 281 Rect mSelectorRect = new Rect(); 282 283 /** 284 * The data set used to store unused views that should be reused during the next layout 285 * to avoid creating new ones 286 */ 287 final RecycleBin mRecycler = new RecycleBin(); 288 289 /** 290 * The selection's left padding 291 */ 292 int mSelectionLeftPadding = 0; 293 294 /** 295 * The selection's top padding 296 */ 297 int mSelectionTopPadding = 0; 298 299 /** 300 * The selection's right padding 301 */ 302 int mSelectionRightPadding = 0; 303 304 /** 305 * The selection's bottom padding 306 */ 307 int mSelectionBottomPadding = 0; 308 309 /** 310 * This view's padding 311 */ 312 Rect mListPadding = new Rect(); 313 314 /** 315 * Subclasses must retain their measure spec from onMeasure() into this member 316 */ 317 int mWidthMeasureSpec = 0; 318 319 /** 320 * The top scroll indicator 321 */ 322 View mScrollUp; 323 324 /** 325 * The down scroll indicator 326 */ 327 View mScrollDown; 328 329 /** 330 * When the view is scrolling, this flag is set to true to indicate subclasses that 331 * the drawing cache was enabled on the children 332 */ 333 boolean mCachingStarted; 334 boolean mCachingActive; 335 336 /** 337 * The position of the view that received the down motion event 338 */ 339 int mMotionPosition; 340 341 /** 342 * The offset to the top of the mMotionPosition view when the down motion event was received 343 */ 344 int mMotionViewOriginalTop; 345 346 /** 347 * The desired offset to the top of the mMotionPosition view after a scroll 348 */ 349 int mMotionViewNewTop; 350 351 /** 352 * The X value associated with the the down motion event 353 */ 354 int mMotionX; 355 356 /** 357 * The Y value associated with the the down motion event 358 */ 359 int mMotionY; 360 361 /** 362 * One of TOUCH_MODE_REST, TOUCH_MODE_DOWN, TOUCH_MODE_TAP, TOUCH_MODE_SCROLL, or 363 * TOUCH_MODE_DONE_WAITING 364 */ 365 int mTouchMode = TOUCH_MODE_REST; 366 367 /** 368 * Y value from on the previous motion event (if any) 369 */ 370 int mLastY; 371 372 /** 373 * How far the finger moved before we started scrolling 374 */ 375 int mMotionCorrection; 376 377 /** 378 * Determines speed during touch scrolling 379 */ 380 private VelocityTracker mVelocityTracker; 381 382 /** 383 * Handles one frame of a fling 384 */ 385 private FlingRunnable mFlingRunnable; 386 387 /** 388 * Handles scrolling between positions within the list. 389 */ 390 private PositionScroller mPositionScroller; 391 392 /** 393 * The offset in pixels form the top of the AdapterView to the top 394 * of the currently selected view. Used to save and restore state. 395 */ 396 int mSelectedTop = 0; 397 398 /** 399 * Indicates whether the list is stacked from the bottom edge or 400 * the top edge. 401 */ 402 boolean mStackFromBottom; 403 404 /** 405 * When set to true, the list automatically discards the children's 406 * bitmap cache after scrolling. 407 */ 408 boolean mScrollingCacheEnabled; 409 410 /** 411 * Whether or not to enable the fast scroll feature on this list 412 */ 413 boolean mFastScrollEnabled; 414 415 /** 416 * Optional callback to notify client when scroll position has changed 417 */ 418 private OnScrollListener mOnScrollListener; 419 420 /** 421 * Keeps track of our accessory window 422 */ 423 PopupWindow mPopup; 424 425 /** 426 * Used with type filter window 427 */ 428 EditText mTextFilter; 429 430 /** 431 * Indicates whether to use pixels-based or position-based scrollbar 432 * properties. 433 */ 434 private boolean mSmoothScrollbarEnabled = true; 435 436 /** 437 * Indicates that this view supports filtering 438 */ 439 private boolean mTextFilterEnabled; 440 441 /** 442 * Indicates that this view is currently displaying a filtered view of the data 443 */ 444 private boolean mFiltered; 445 446 /** 447 * Rectangle used for hit testing children 448 */ 449 private Rect mTouchFrame; 450 451 /** 452 * The position to resurrect the selected position to. 453 */ 454 int mResurrectToPosition = INVALID_POSITION; 455 456 private ContextMenuInfo mContextMenuInfo = null; 457 458 /** 459 * Maximum distance to record overscroll 460 */ 461 int mOverscrollMax; 462 463 /** 464 * Content height divided by this is the overscroll limit. 465 */ 466 static final int OVERSCROLL_LIMIT_DIVISOR = 3; 467 468 /** 469 * Used to request a layout when we changed touch mode 470 */ 471 private static final int TOUCH_MODE_UNKNOWN = -1; 472 private static final int TOUCH_MODE_ON = 0; 473 private static final int TOUCH_MODE_OFF = 1; 474 475 private int mLastTouchMode = TOUCH_MODE_UNKNOWN; 476 477 private static final boolean PROFILE_SCROLLING = false; 478 private boolean mScrollProfilingStarted = false; 479 480 private static final boolean PROFILE_FLINGING = false; 481 private boolean mFlingProfilingStarted = false; 482 483 /** 484 * The StrictMode "critical time span" objects to catch animation 485 * stutters. Non-null when a time-sensitive animation is 486 * in-flight. Must call finish() on them when done animating. 487 * These are no-ops on user builds. 488 */ 489 private StrictMode.Span mScrollStrictSpan = null; 490 private StrictMode.Span mFlingStrictSpan = null; 491 492 /** 493 * The last CheckForLongPress runnable we posted, if any 494 */ 495 private CheckForLongPress mPendingCheckForLongPress; 496 497 /** 498 * The last CheckForTap runnable we posted, if any 499 */ 500 private Runnable mPendingCheckForTap; 501 502 /** 503 * The last CheckForKeyLongPress runnable we posted, if any 504 */ 505 private CheckForKeyLongPress mPendingCheckForKeyLongPress; 506 507 /** 508 * Acts upon click 509 */ 510 private AbsListView.PerformClick mPerformClick; 511 512 /** 513 * Delayed action for touch mode. 514 */ 515 private Runnable mTouchModeReset; 516 517 /** 518 * This view is in transcript mode -- it shows the bottom of the list when the data 519 * changes 520 */ 521 private int mTranscriptMode; 522 523 /** 524 * Indicates that this list is always drawn on top of a solid, single-color, opaque 525 * background 526 */ 527 private int mCacheColorHint; 528 529 /** 530 * The select child's view (from the adapter's getView) is enabled. 531 */ 532 private boolean mIsChildViewEnabled; 533 534 /** 535 * The last scroll state reported to clients through {@link OnScrollListener}. 536 */ 537 private int mLastScrollState = OnScrollListener.SCROLL_STATE_IDLE; 538 539 /** 540 * Helper object that renders and controls the fast scroll thumb. 541 */ 542 private FastScroller mFastScroller; 543 544 private boolean mGlobalLayoutListenerAddedFilter; 545 546 private int mTouchSlop; 547 private float mDensityScale; 548 549 private InputConnection mDefInputConnection; 550 private InputConnectionWrapper mPublicInputConnection; 551 552 private Runnable mClearScrollingCache; 553 private int mMinimumVelocity; 554 private int mMaximumVelocity; 555 private float mVelocityScale = 1.0f; 556 557 final boolean[] mIsScrap = new boolean[1]; 558 559 // True when the popup should be hidden because of a call to 560 // dispatchDisplayHint() 561 private boolean mPopupHidden; 562 563 /** 564 * ID of the active pointer. This is used to retain consistency during 565 * drags/flings if multiple pointers are used. 566 */ 567 private int mActivePointerId = INVALID_POINTER; 568 569 /** 570 * Sentinel value for no current active pointer. 571 * Used by {@link #mActivePointerId}. 572 */ 573 private static final int INVALID_POINTER = -1; 574 575 /** 576 * Maximum distance to overscroll by during edge effects 577 */ 578 int mOverscrollDistance; 579 580 /** 581 * Maximum distance to overfling during edge effects 582 */ 583 int mOverflingDistance; 584 585 // These two EdgeGlows are always set and used together. 586 // Checking one for null is as good as checking both. 587 588 /** 589 * Tracks the state of the top edge glow. 590 */ 591 private EdgeGlow mEdgeGlowTop; 592 593 /** 594 * Tracks the state of the bottom edge glow. 595 */ 596 private EdgeGlow mEdgeGlowBottom; 597 598 /** 599 * An estimate of how many pixels are between the top of the list and 600 * the top of the first position in the adapter, based on the last time 601 * we saw it. Used to hint where to draw edge glows. 602 */ 603 private int mFirstPositionDistanceGuess; 604 605 /** 606 * An estimate of how many pixels are between the bottom of the list and 607 * the bottom of the last position in the adapter, based on the last time 608 * we saw it. Used to hint where to draw edge glows. 609 */ 610 private int mLastPositionDistanceGuess; 611 612 /** 613 * Used for determining when to cancel out of overscroll. 614 */ 615 private int mDirection = 0; 616 617 /** 618 * Tracked on measurement in transcript mode. Makes sure that we can still pin to 619 * the bottom correctly on resizes. 620 */ 621 private boolean mForceTranscriptScroll; 622 623 private int mGlowPaddingLeft; 624 private int mGlowPaddingRight; 625 626 /** 627 * Interface definition for a callback to be invoked when the list or grid 628 * has been scrolled. 629 */ 630 public interface OnScrollListener { 631 632 /** 633 * The view is not scrolling. Note navigating the list using the trackball counts as 634 * being in the idle state since these transitions are not animated. 635 */ 636 public static int SCROLL_STATE_IDLE = 0; 637 638 /** 639 * The user is scrolling using touch, and their finger is still on the screen 640 */ 641 public static int SCROLL_STATE_TOUCH_SCROLL = 1; 642 643 /** 644 * The user had previously been scrolling using touch and had performed a fling. The 645 * animation is now coasting to a stop 646 */ 647 public static int SCROLL_STATE_FLING = 2; 648 649 /** 650 * Callback method to be invoked while the list view or grid view is being scrolled. If the 651 * view is being scrolled, this method will be called before the next frame of the scroll is 652 * rendered. In particular, it will be called before any calls to 653 * {@link Adapter#getView(int, View, ViewGroup)}. 654 * 655 * @param view The view whose scroll state is being reported 656 * 657 * @param scrollState The current scroll state. One of {@link #SCROLL_STATE_IDLE}, 658 * {@link #SCROLL_STATE_TOUCH_SCROLL} or {@link #SCROLL_STATE_IDLE}. 659 */ 660 public void onScrollStateChanged(AbsListView view, int scrollState); 661 662 /** 663 * Callback method to be invoked when the list or grid has been scrolled. This will be 664 * called after the scroll has completed 665 * @param view The view whose scroll state is being reported 666 * @param firstVisibleItem the index of the first visible cell (ignore if 667 * visibleItemCount == 0) 668 * @param visibleItemCount the number of visible cells 669 * @param totalItemCount the number of items in the list adaptor 670 */ 671 public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, 672 int totalItemCount); 673 } 674 675 /** 676 * The top-level view of a list item can implement this interface to allow 677 * itself to modify the bounds of the selection shown for that item. 678 */ 679 public interface SelectionBoundsAdjuster { 680 /** 681 * Called to allow the list item to adjust the bounds shown for 682 * its selection. 683 * 684 * @param bounds On call, this contains the bounds the list has 685 * selected for the item (that is the bounds of the entire view). The 686 * values can be modified as desired. 687 */ 688 public void adjustListItemSelectionBounds(Rect bounds); 689 } 690 691 public AbsListView(Context context) { 692 super(context); 693 initAbsListView(); 694 695 setVerticalScrollBarEnabled(true); 696 TypedArray a = context.obtainStyledAttributes(R.styleable.View); 697 initializeScrollbars(a); 698 a.recycle(); 699 } 700 701 public AbsListView(Context context, AttributeSet attrs) { 702 this(context, attrs, com.android.internal.R.attr.absListViewStyle); 703 } 704 705 public AbsListView(Context context, AttributeSet attrs, int defStyle) { 706 super(context, attrs, defStyle); 707 initAbsListView(); 708 709 TypedArray a = context.obtainStyledAttributes(attrs, 710 com.android.internal.R.styleable.AbsListView, defStyle, 0); 711 712 Drawable d = a.getDrawable(com.android.internal.R.styleable.AbsListView_listSelector); 713 if (d != null) { 714 setSelector(d); 715 } 716 717 mDrawSelectorOnTop = a.getBoolean( 718 com.android.internal.R.styleable.AbsListView_drawSelectorOnTop, false); 719 720 boolean stackFromBottom = a.getBoolean(R.styleable.AbsListView_stackFromBottom, false); 721 setStackFromBottom(stackFromBottom); 722 723 boolean scrollingCacheEnabled = a.getBoolean(R.styleable.AbsListView_scrollingCache, true); 724 setScrollingCacheEnabled(scrollingCacheEnabled); 725 726 boolean useTextFilter = a.getBoolean(R.styleable.AbsListView_textFilterEnabled, false); 727 setTextFilterEnabled(useTextFilter); 728 729 int transcriptMode = a.getInt(R.styleable.AbsListView_transcriptMode, 730 TRANSCRIPT_MODE_DISABLED); 731 setTranscriptMode(transcriptMode); 732 733 int color = a.getColor(R.styleable.AbsListView_cacheColorHint, 0); 734 setCacheColorHint(color); 735 736 boolean enableFastScroll = a.getBoolean(R.styleable.AbsListView_fastScrollEnabled, false); 737 setFastScrollEnabled(enableFastScroll); 738 739 boolean smoothScrollbar = a.getBoolean(R.styleable.AbsListView_smoothScrollbar, true); 740 setSmoothScrollbarEnabled(smoothScrollbar); 741 742 setChoiceMode(a.getInt(R.styleable.AbsListView_choiceMode, CHOICE_MODE_NONE)); 743 setFastScrollAlwaysVisible( 744 a.getBoolean(R.styleable.AbsListView_fastScrollAlwaysVisible, false)); 745 746 a.recycle(); 747 } 748 749 private void initAbsListView() { 750 // Setting focusable in touch mode will set the focusable property to true 751 setClickable(true); 752 setFocusableInTouchMode(true); 753 setWillNotDraw(false); 754 setAlwaysDrawnWithCacheEnabled(false); 755 setScrollingCacheEnabled(true); 756 757 final ViewConfiguration configuration = ViewConfiguration.get(mContext); 758 mTouchSlop = configuration.getScaledTouchSlop(); 759 mMinimumVelocity = configuration.getScaledMinimumFlingVelocity(); 760 mMaximumVelocity = configuration.getScaledMaximumFlingVelocity(); 761 mOverscrollDistance = configuration.getScaledOverscrollDistance(); 762 mOverflingDistance = configuration.getScaledOverflingDistance(); 763 764 mDensityScale = getContext().getResources().getDisplayMetrics().density; 765 } 766 767 @Override 768 public void setOverScrollMode(int mode) { 769 if (mode != OVER_SCROLL_NEVER) { 770 if (mEdgeGlowTop == null) { 771 Context context = getContext(); 772 final Resources res = context.getResources(); 773 final Drawable edge = res.getDrawable(R.drawable.overscroll_edge); 774 final Drawable glow = res.getDrawable(R.drawable.overscroll_glow); 775 mEdgeGlowTop = new EdgeGlow(context, edge, glow); 776 mEdgeGlowBottom = new EdgeGlow(context, edge, glow); 777 } 778 } else { 779 mEdgeGlowTop = null; 780 mEdgeGlowBottom = null; 781 } 782 super.setOverScrollMode(mode); 783 } 784 785 /** 786 * {@inheritDoc} 787 */ 788 @Override 789 public void setAdapter(ListAdapter adapter) { 790 if (adapter != null) { 791 if (mChoiceMode != CHOICE_MODE_NONE && mAdapter.hasStableIds() && 792 mCheckedIdStates == null) { 793 mCheckedIdStates = new LongSparseArray<Boolean>(); 794 } 795 } 796 797 if (mCheckStates != null) { 798 mCheckStates.clear(); 799 } 800 801 if (mCheckedIdStates != null) { 802 mCheckedIdStates.clear(); 803 } 804 } 805 806 /** 807 * Returns the number of items currently selected. This will only be valid 808 * if the choice mode is not {@link #CHOICE_MODE_NONE} (default). 809 * 810 * <p>To determine the specific items that are currently selected, use one of 811 * the <code>getChecked*</code> methods. 812 * 813 * @return The number of items currently selected 814 * 815 * @see #getCheckedItemPosition() 816 * @see #getCheckedItemPositions() 817 * @see #getCheckedItemIds() 818 */ 819 public int getCheckedItemCount() { 820 return mCheckedItemCount; 821 } 822 823 /** 824 * Returns the checked state of the specified position. The result is only 825 * valid if the choice mode has been set to {@link #CHOICE_MODE_SINGLE} 826 * or {@link #CHOICE_MODE_MULTIPLE}. 827 * 828 * @param position The item whose checked state to return 829 * @return The item's checked state or <code>false</code> if choice mode 830 * is invalid 831 * 832 * @see #setChoiceMode(int) 833 */ 834 public boolean isItemChecked(int position) { 835 if (mChoiceMode != CHOICE_MODE_NONE && mCheckStates != null) { 836 return mCheckStates.get(position); 837 } 838 839 return false; 840 } 841 842 /** 843 * Returns the currently checked item. The result is only valid if the choice 844 * mode has been set to {@link #CHOICE_MODE_SINGLE}. 845 * 846 * @return The position of the currently checked item or 847 * {@link #INVALID_POSITION} if nothing is selected 848 * 849 * @see #setChoiceMode(int) 850 */ 851 public int getCheckedItemPosition() { 852 if (mChoiceMode == CHOICE_MODE_SINGLE && mCheckStates != null && mCheckStates.size() == 1) { 853 return mCheckStates.keyAt(0); 854 } 855 856 return INVALID_POSITION; 857 } 858 859 /** 860 * Returns the set of checked items in the list. The result is only valid if 861 * the choice mode has not been set to {@link #CHOICE_MODE_NONE}. 862 * 863 * @return A SparseBooleanArray which will return true for each call to 864 * get(int position) where position is a position in the list, 865 * or <code>null</code> if the choice mode is set to 866 * {@link #CHOICE_MODE_NONE}. 867 */ 868 public SparseBooleanArray getCheckedItemPositions() { 869 if (mChoiceMode != CHOICE_MODE_NONE) { 870 return mCheckStates; 871 } 872 return null; 873 } 874 875 /** 876 * Returns the set of checked items ids. The result is only valid if the 877 * choice mode has not been set to {@link #CHOICE_MODE_NONE} and the adapter 878 * has stable IDs. ({@link ListAdapter#hasStableIds()} == {@code true}) 879 * 880 * @return A new array which contains the id of each checked item in the 881 * list. 882 */ 883 public long[] getCheckedItemIds() { 884 if (mChoiceMode == CHOICE_MODE_NONE || mCheckedIdStates == null || mAdapter == null) { 885 return new long[0]; 886 } 887 888 final LongSparseArray<Boolean> idStates = mCheckedIdStates; 889 final int count = idStates.size(); 890 final long[] ids = new long[count]; 891 892 for (int i = 0; i < count; i++) { 893 ids[i] = idStates.keyAt(i); 894 } 895 896 return ids; 897 } 898 899 /** 900 * Clear any choices previously set 901 */ 902 public void clearChoices() { 903 if (mCheckStates != null) { 904 mCheckStates.clear(); 905 } 906 if (mCheckedIdStates != null) { 907 mCheckedIdStates.clear(); 908 } 909 mCheckedItemCount = 0; 910 } 911 912 /** 913 * Sets the checked state of the specified position. The is only valid if 914 * the choice mode has been set to {@link #CHOICE_MODE_SINGLE} or 915 * {@link #CHOICE_MODE_MULTIPLE}. 916 * 917 * @param position The item whose checked state is to be checked 918 * @param value The new checked state for the item 919 */ 920 public void setItemChecked(int position, boolean value) { 921 if (mChoiceMode == CHOICE_MODE_NONE) { 922 return; 923 } 924 925 // Start selection mode if needed. We don't need to if we're unchecking something. 926 if (value && mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL && mChoiceActionMode == null) { 927 mChoiceActionMode = startActionMode(mMultiChoiceModeCallback); 928 } 929 930 if (mChoiceMode == CHOICE_MODE_MULTIPLE || mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL) { 931 boolean oldValue = mCheckStates.get(position); 932 mCheckStates.put(position, value); 933 if (mCheckedIdStates != null && mAdapter.hasStableIds()) { 934 if (value) { 935 mCheckedIdStates.put(mAdapter.getItemId(position), Boolean.TRUE); 936 } else { 937 mCheckedIdStates.delete(mAdapter.getItemId(position)); 938 } 939 } 940 if (oldValue != value) { 941 if (value) { 942 mCheckedItemCount++; 943 } else { 944 mCheckedItemCount--; 945 } 946 } 947 if (mChoiceActionMode != null) { 948 final long id = mAdapter.getItemId(position); 949 mMultiChoiceModeCallback.onItemCheckedStateChanged(mChoiceActionMode, 950 position, id, value); 951 } 952 } else { 953 boolean updateIds = mCheckedIdStates != null && mAdapter.hasStableIds(); 954 // Clear all values if we're checking something, or unchecking the currently 955 // selected item 956 if (value || isItemChecked(position)) { 957 mCheckStates.clear(); 958 if (updateIds) { 959 mCheckedIdStates.clear(); 960 } 961 } 962 // this may end up selecting the value we just cleared but this way 963 // we ensure length of mCheckStates is 1, a fact getCheckedItemPosition relies on 964 if (value) { 965 mCheckStates.put(position, true); 966 if (updateIds) { 967 mCheckedIdStates.put(mAdapter.getItemId(position), Boolean.TRUE); 968 } 969 mCheckedItemCount = 1; 970 } else if (mCheckStates.size() == 0 || !mCheckStates.valueAt(0)) { 971 mCheckedItemCount = 0; 972 } 973 } 974 975 // Do not generate a data change while we are in the layout phase 976 if (!mInLayout && !mBlockLayoutRequests) { 977 mDataChanged = true; 978 rememberSyncState(); 979 requestLayout(); 980 } 981 } 982 983 @Override 984 public boolean performItemClick(View view, int position, long id) { 985 boolean handled = false; 986 boolean dispatchItemClick = true; 987 988 if (mChoiceMode != CHOICE_MODE_NONE) { 989 handled = true; 990 991 if (mChoiceMode == CHOICE_MODE_MULTIPLE || 992 (mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL && mChoiceActionMode != null)) { 993 boolean newValue = !mCheckStates.get(position, false); 994 mCheckStates.put(position, newValue); 995 if (mCheckedIdStates != null && mAdapter.hasStableIds()) { 996 if (newValue) { 997 mCheckedIdStates.put(mAdapter.getItemId(position), Boolean.TRUE); 998 } else { 999 mCheckedIdStates.delete(mAdapter.getItemId(position)); 1000 } 1001 } 1002 if (newValue) { 1003 mCheckedItemCount++; 1004 } else { 1005 mCheckedItemCount--; 1006 } 1007 if (mChoiceActionMode != null) { 1008 mMultiChoiceModeCallback.onItemCheckedStateChanged(mChoiceActionMode, 1009 position, id, newValue); 1010 dispatchItemClick = false; 1011 } 1012 } else if (mChoiceMode == CHOICE_MODE_SINGLE) { 1013 boolean newValue = !mCheckStates.get(position, false); 1014 if (newValue) { 1015 mCheckStates.clear(); 1016 mCheckStates.put(position, true); 1017 if (mCheckedIdStates != null && mAdapter.hasStableIds()) { 1018 mCheckedIdStates.clear(); 1019 mCheckedIdStates.put(mAdapter.getItemId(position), Boolean.TRUE); 1020 } 1021 mCheckedItemCount = 1; 1022 } else if (mCheckStates.size() == 0 || !mCheckStates.valueAt(0)) { 1023 mCheckedItemCount = 0; 1024 } 1025 } 1026 1027 mDataChanged = true; 1028 rememberSyncState(); 1029 requestLayout(); 1030 } 1031 1032 if (dispatchItemClick) { 1033 handled |= super.performItemClick(view, position, id); 1034 } 1035 1036 return handled; 1037 } 1038 1039 /** 1040 * @see #setChoiceMode(int) 1041 * 1042 * @return The current choice mode 1043 */ 1044 public int getChoiceMode() { 1045 return mChoiceMode; 1046 } 1047 1048 /** 1049 * Defines the choice behavior for the List. By default, Lists do not have any choice behavior 1050 * ({@link #CHOICE_MODE_NONE}). By setting the choiceMode to {@link #CHOICE_MODE_SINGLE}, the 1051 * List allows up to one item to be in a chosen state. By setting the choiceMode to 1052 * {@link #CHOICE_MODE_MULTIPLE}, the list allows any number of items to be chosen. 1053 * 1054 * @param choiceMode One of {@link #CHOICE_MODE_NONE}, {@link #CHOICE_MODE_SINGLE}, or 1055 * {@link #CHOICE_MODE_MULTIPLE} 1056 */ 1057 public void setChoiceMode(int choiceMode) { 1058 mChoiceMode = choiceMode; 1059 if (mChoiceActionMode != null) { 1060 mChoiceActionMode.finish(); 1061 mChoiceActionMode = null; 1062 } 1063 if (mChoiceMode != CHOICE_MODE_NONE) { 1064 if (mCheckStates == null) { 1065 mCheckStates = new SparseBooleanArray(); 1066 } 1067 if (mCheckedIdStates == null && mAdapter != null && mAdapter.hasStableIds()) { 1068 mCheckedIdStates = new LongSparseArray<Boolean>(); 1069 } 1070 // Modal multi-choice mode only has choices when the mode is active. Clear them. 1071 if (mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL) { 1072 clearChoices(); 1073 setLongClickable(true); 1074 } 1075 } 1076 } 1077 1078 /** 1079 * Set a {@link MultiChoiceModeListener} that will manage the lifecycle of the 1080 * selection {@link ActionMode}. Only used when the choice mode is set to 1081 * {@link #CHOICE_MODE_MULTIPLE_MODAL}. 1082 * 1083 * @param listener Listener that will manage the selection mode 1084 * 1085 * @see #setChoiceMode(int) 1086 */ 1087 public void setMultiChoiceModeListener(MultiChoiceModeListener listener) { 1088 if (mMultiChoiceModeCallback == null) { 1089 mMultiChoiceModeCallback = new MultiChoiceModeWrapper(); 1090 } 1091 mMultiChoiceModeCallback.setWrapped(listener); 1092 } 1093 1094 /** 1095 * @return true if all list content currently fits within the view boundaries 1096 */ 1097 private boolean contentFits() { 1098 final int childCount = getChildCount(); 1099 if (childCount == 0) return true; 1100 if (childCount != mItemCount) return false; 1101 1102 return getChildAt(0).getTop() >= mListPadding.top && 1103 getChildAt(childCount - 1).getBottom() <= getHeight() - mListPadding.bottom; 1104 } 1105 1106 /** 1107 * Enables fast scrolling by letting the user quickly scroll through lists by 1108 * dragging the fast scroll thumb. The adapter attached to the list may want 1109 * to implement {@link SectionIndexer} if it wishes to display alphabet preview and 1110 * jump between sections of the list. 1111 * @see SectionIndexer 1112 * @see #isFastScrollEnabled() 1113 * @param enabled whether or not to enable fast scrolling 1114 */ 1115 public void setFastScrollEnabled(boolean enabled) { 1116 mFastScrollEnabled = enabled; 1117 if (enabled) { 1118 if (mFastScroller == null) { 1119 mFastScroller = new FastScroller(getContext(), this); 1120 } 1121 } else { 1122 if (mFastScroller != null) { 1123 mFastScroller.stop(); 1124 mFastScroller = null; 1125 } 1126 } 1127 } 1128 1129 /** 1130 * Set whether or not the fast scroller should always be shown in place of the 1131 * standard scrollbars. Fast scrollers shown in this way will not fade out and will 1132 * be a permanent fixture within the list. Best combined with an inset scroll bar style 1133 * that will ensure enough padding. This will enable fast scrolling if it is not 1134 * already enabled. 1135 * 1136 * @param alwaysShow true if the fast scroller should always be displayed. 1137 * @see #setScrollBarStyle(int) 1138 * @see #setFastScrollEnabled(boolean) 1139 */ 1140 public void setFastScrollAlwaysVisible(boolean alwaysShow) { 1141 if (alwaysShow && !mFastScrollEnabled) { 1142 setFastScrollEnabled(true); 1143 } 1144 1145 if (mFastScroller != null) { 1146 mFastScroller.setAlwaysShow(alwaysShow); 1147 } 1148 1149 computeOpaqueFlags(); 1150 recomputePadding(); 1151 } 1152 1153 /** 1154 * Returns true if the fast scroller is set to always show on this view rather than 1155 * fade out when not in use. 1156 * 1157 * @return true if the fast scroller will always show. 1158 * @see #setFastScrollAlwaysVisible(boolean) 1159 */ 1160 public boolean isFastScrollAlwaysVisible() { 1161 return mFastScrollEnabled && mFastScroller.isAlwaysShowEnabled(); 1162 } 1163 1164 @Override 1165 public int getVerticalScrollbarWidth() { 1166 if (isFastScrollAlwaysVisible()) { 1167 return Math.max(super.getVerticalScrollbarWidth(), mFastScroller.getWidth()); 1168 } 1169 return super.getVerticalScrollbarWidth(); 1170 } 1171 1172 /** 1173 * Returns the current state of the fast scroll feature. 1174 * @see #setFastScrollEnabled(boolean) 1175 * @return true if fast scroll is enabled, false otherwise 1176 */ 1177 @ViewDebug.ExportedProperty 1178 public boolean isFastScrollEnabled() { 1179 return mFastScrollEnabled; 1180 } 1181 1182 @Override 1183 public void setVerticalScrollbarPosition(int position) { 1184 super.setVerticalScrollbarPosition(position); 1185 if (mFastScroller != null) { 1186 mFastScroller.setScrollbarPosition(position); 1187 } 1188 } 1189 1190 /** 1191 * If fast scroll is visible, then don't draw the vertical scrollbar. 1192 * @hide 1193 */ 1194 @Override 1195 protected boolean isVerticalScrollBarHidden() { 1196 return mFastScroller != null && mFastScroller.isVisible(); 1197 } 1198 1199 /** 1200 * When smooth scrollbar is enabled, the position and size of the scrollbar thumb 1201 * is computed based on the number of visible pixels in the visible items. This 1202 * however assumes that all list items have the same height. If you use a list in 1203 * which items have different heights, the scrollbar will change appearance as the 1204 * user scrolls through the list. To avoid this issue, you need to disable this 1205 * property. 1206 * 1207 * When smooth scrollbar is disabled, the position and size of the scrollbar thumb 1208 * is based solely on the number of items in the adapter and the position of the 1209 * visible items inside the adapter. This provides a stable scrollbar as the user 1210 * navigates through a list of items with varying heights. 1211 * 1212 * @param enabled Whether or not to enable smooth scrollbar. 1213 * 1214 * @see #setSmoothScrollbarEnabled(boolean) 1215 * @attr ref android.R.styleable#AbsListView_smoothScrollbar 1216 */ 1217 public void setSmoothScrollbarEnabled(boolean enabled) { 1218 mSmoothScrollbarEnabled = enabled; 1219 } 1220 1221 /** 1222 * Returns the current state of the fast scroll feature. 1223 * 1224 * @return True if smooth scrollbar is enabled is enabled, false otherwise. 1225 * 1226 * @see #setSmoothScrollbarEnabled(boolean) 1227 */ 1228 @ViewDebug.ExportedProperty 1229 public boolean isSmoothScrollbarEnabled() { 1230 return mSmoothScrollbarEnabled; 1231 } 1232 1233 /** 1234 * Set the listener that will receive notifications every time the list scrolls. 1235 * 1236 * @param l the scroll listener 1237 */ 1238 public void setOnScrollListener(OnScrollListener l) { 1239 mOnScrollListener = l; 1240 invokeOnItemScrollListener(); 1241 } 1242 1243 /** 1244 * Notify our scroll listener (if there is one) of a change in scroll state 1245 */ 1246 void invokeOnItemScrollListener() { 1247 if (mFastScroller != null) { 1248 mFastScroller.onScroll(this, mFirstPosition, getChildCount(), mItemCount); 1249 } 1250 if (mOnScrollListener != null) { 1251 mOnScrollListener.onScroll(this, mFirstPosition, getChildCount(), mItemCount); 1252 } 1253 onScrollChanged(0, 0, 0, 0); // dummy values, View's implementation does not use these. 1254 } 1255 1256 @Override 1257 public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) { 1258 super.onInitializeAccessibilityNodeInfo(info); 1259 info.setScrollable(true); 1260 } 1261 1262 @Override 1263 public void onInitializeAccessibilityEvent(AccessibilityEvent event) { 1264 super.onInitializeAccessibilityEvent(event); 1265 event.setScrollable(true); 1266 if (event.getEventType() == AccessibilityEvent.TYPE_VIEW_SCROLLED) { 1267 event.setFromIndex(mFirstPosition); 1268 event.setToIndex(mFirstPosition + getChildCount()); 1269 event.setItemCount(mItemCount); 1270 } 1271 } 1272 1273 @Override 1274 public boolean dispatchPopulateAccessibilityEvent(AccessibilityEvent event) { 1275 // Do not append text content to scroll events they are fired frequently 1276 // and the client has already received another event type with the text. 1277 if (event.getEventType() != AccessibilityEvent.TYPE_VIEW_SCROLLED) { 1278 super.dispatchPopulateAccessibilityEvent(event); 1279 } 1280 return false; 1281 } 1282 1283 /** 1284 * Indicates whether the children's drawing cache is used during a scroll. 1285 * By default, the drawing cache is enabled but this will consume more memory. 1286 * 1287 * @return true if the scrolling cache is enabled, false otherwise 1288 * 1289 * @see #setScrollingCacheEnabled(boolean) 1290 * @see View#setDrawingCacheEnabled(boolean) 1291 */ 1292 @ViewDebug.ExportedProperty 1293 public boolean isScrollingCacheEnabled() { 1294 return mScrollingCacheEnabled; 1295 } 1296 1297 /** 1298 * Enables or disables the children's drawing cache during a scroll. 1299 * By default, the drawing cache is enabled but this will use more memory. 1300 * 1301 * When the scrolling cache is enabled, the caches are kept after the 1302 * first scrolling. You can manually clear the cache by calling 1303 * {@link android.view.ViewGroup#setChildrenDrawingCacheEnabled(boolean)}. 1304 * 1305 * @param enabled true to enable the scroll cache, false otherwise 1306 * 1307 * @see #isScrollingCacheEnabled() 1308 * @see View#setDrawingCacheEnabled(boolean) 1309 */ 1310 public void setScrollingCacheEnabled(boolean enabled) { 1311 if (mScrollingCacheEnabled && !enabled) { 1312 clearScrollingCache(); 1313 } 1314 mScrollingCacheEnabled = enabled; 1315 } 1316 1317 /** 1318 * Enables or disables the type filter window. If enabled, typing when 1319 * this view has focus will filter the children to match the users input. 1320 * Note that the {@link Adapter} used by this view must implement the 1321 * {@link Filterable} interface. 1322 * 1323 * @param textFilterEnabled true to enable type filtering, false otherwise 1324 * 1325 * @see Filterable 1326 */ 1327 public void setTextFilterEnabled(boolean textFilterEnabled) { 1328 mTextFilterEnabled = textFilterEnabled; 1329 } 1330 1331 /** 1332 * Indicates whether type filtering is enabled for this view 1333 * 1334 * @return true if type filtering is enabled, false otherwise 1335 * 1336 * @see #setTextFilterEnabled(boolean) 1337 * @see Filterable 1338 */ 1339 @ViewDebug.ExportedProperty 1340 public boolean isTextFilterEnabled() { 1341 return mTextFilterEnabled; 1342 } 1343 1344 @Override 1345 public void getFocusedRect(Rect r) { 1346 View view = getSelectedView(); 1347 if (view != null && view.getParent() == this) { 1348 // the focused rectangle of the selected view offset into the 1349 // coordinate space of this view. 1350 view.getFocusedRect(r); 1351 offsetDescendantRectToMyCoords(view, r); 1352 } else { 1353 // otherwise, just the norm 1354 super.getFocusedRect(r); 1355 } 1356 } 1357 1358 private void useDefaultSelector() { 1359 setSelector(getResources().getDrawable( 1360 com.android.internal.R.drawable.list_selector_background)); 1361 } 1362 1363 /** 1364 * Indicates whether the content of this view is pinned to, or stacked from, 1365 * the bottom edge. 1366 * 1367 * @return true if the content is stacked from the bottom edge, false otherwise 1368 */ 1369 @ViewDebug.ExportedProperty 1370 public boolean isStackFromBottom() { 1371 return mStackFromBottom; 1372 } 1373 1374 /** 1375 * When stack from bottom is set to true, the list fills its content starting from 1376 * the bottom of the view. 1377 * 1378 * @param stackFromBottom true to pin the view's content to the bottom edge, 1379 * false to pin the view's content to the top edge 1380 */ 1381 public void setStackFromBottom(boolean stackFromBottom) { 1382 if (mStackFromBottom != stackFromBottom) { 1383 mStackFromBottom = stackFromBottom; 1384 requestLayoutIfNecessary(); 1385 } 1386 } 1387 1388 void requestLayoutIfNecessary() { 1389 if (getChildCount() > 0) { 1390 resetList(); 1391 requestLayout(); 1392 invalidate(); 1393 } 1394 } 1395 1396 static class SavedState extends BaseSavedState { 1397 long selectedId; 1398 long firstId; 1399 int viewTop; 1400 int position; 1401 int height; 1402 String filter; 1403 boolean inActionMode; 1404 int checkedItemCount; 1405 SparseBooleanArray checkState; 1406 LongSparseArray<Boolean> checkIdState; 1407 1408 /** 1409 * Constructor called from {@link AbsListView#onSaveInstanceState()} 1410 */ 1411 SavedState(Parcelable superState) { 1412 super(superState); 1413 } 1414 1415 /** 1416 * Constructor called from {@link #CREATOR} 1417 */ 1418 private SavedState(Parcel in) { 1419 super(in); 1420 selectedId = in.readLong(); 1421 firstId = in.readLong(); 1422 viewTop = in.readInt(); 1423 position = in.readInt(); 1424 height = in.readInt(); 1425 filter = in.readString(); 1426 inActionMode = in.readByte() != 0; 1427 checkedItemCount = in.readInt(); 1428 checkState = in.readSparseBooleanArray(); 1429 long[] idState = in.createLongArray(); 1430 1431 if (idState.length > 0) { 1432 checkIdState = new LongSparseArray<Boolean>(); 1433 checkIdState.setValues(idState, Boolean.TRUE); 1434 } 1435 } 1436 1437 @Override 1438 public void writeToParcel(Parcel out, int flags) { 1439 super.writeToParcel(out, flags); 1440 out.writeLong(selectedId); 1441 out.writeLong(firstId); 1442 out.writeInt(viewTop); 1443 out.writeInt(position); 1444 out.writeInt(height); 1445 out.writeString(filter); 1446 out.writeByte((byte) (inActionMode ? 1 : 0)); 1447 out.writeInt(checkedItemCount); 1448 out.writeSparseBooleanArray(checkState); 1449 out.writeLongArray(checkIdState != null ? checkIdState.getKeys() : new long[0]); 1450 } 1451 1452 @Override 1453 public String toString() { 1454 return "AbsListView.SavedState{" 1455 + Integer.toHexString(System.identityHashCode(this)) 1456 + " selectedId=" + selectedId 1457 + " firstId=" + firstId 1458 + " viewTop=" + viewTop 1459 + " position=" + position 1460 + " height=" + height 1461 + " filter=" + filter 1462 + " checkState=" + checkState + "}"; 1463 } 1464 1465 public static final Parcelable.Creator<SavedState> CREATOR 1466 = new Parcelable.Creator<SavedState>() { 1467 public SavedState createFromParcel(Parcel in) { 1468 return new SavedState(in); 1469 } 1470 1471 public SavedState[] newArray(int size) { 1472 return new SavedState[size]; 1473 } 1474 }; 1475 } 1476 1477 @Override 1478 public Parcelable onSaveInstanceState() { 1479 /* 1480 * This doesn't really make sense as the place to dismiss the 1481 * popups, but there don't seem to be any other useful hooks 1482 * that happen early enough to keep from getting complaints 1483 * about having leaked the window. 1484 */ 1485 dismissPopup(); 1486 1487 Parcelable superState = super.onSaveInstanceState(); 1488 1489 SavedState ss = new SavedState(superState); 1490 1491 boolean haveChildren = getChildCount() > 0 && mItemCount > 0; 1492 long selectedId = getSelectedItemId(); 1493 ss.selectedId = selectedId; 1494 ss.height = getHeight(); 1495 1496 if (selectedId >= 0) { 1497 // Remember the selection 1498 ss.viewTop = mSelectedTop; 1499 ss.position = getSelectedItemPosition(); 1500 ss.firstId = INVALID_POSITION; 1501 } else { 1502 if (haveChildren && mFirstPosition > 0) { 1503 // Remember the position of the first child. 1504 // We only do this if we are not currently at the top of 1505 // the list, for two reasons: 1506 // (1) The list may be in the process of becoming empty, in 1507 // which case mItemCount may not be 0, but if we try to 1508 // ask for any information about position 0 we will crash. 1509 // (2) Being "at the top" seems like a special case, anyway, 1510 // and the user wouldn't expect to end up somewhere else when 1511 // they revisit the list even if its content has changed. 1512 View v = getChildAt(0); 1513 ss.viewTop = v.getTop(); 1514 int firstPos = mFirstPosition; 1515 if (firstPos >= mItemCount) { 1516 firstPos = mItemCount - 1; 1517 } 1518 ss.position = firstPos; 1519 ss.firstId = mAdapter.getItemId(firstPos); 1520 } else { 1521 ss.viewTop = 0; 1522 ss.firstId = INVALID_POSITION; 1523 ss.position = 0; 1524 } 1525 } 1526 1527 ss.filter = null; 1528 if (mFiltered) { 1529 final EditText textFilter = mTextFilter; 1530 if (textFilter != null) { 1531 Editable filterText = textFilter.getText(); 1532 if (filterText != null) { 1533 ss.filter = filterText.toString(); 1534 } 1535 } 1536 } 1537 1538 ss.inActionMode = mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL && mChoiceActionMode != null; 1539 1540 ss.checkState = mCheckStates; 1541 ss.checkIdState = mCheckedIdStates; 1542 ss.checkedItemCount = mCheckedItemCount; 1543 1544 return ss; 1545 } 1546 1547 @Override 1548 public void onRestoreInstanceState(Parcelable state) { 1549 SavedState ss = (SavedState) state; 1550 1551 super.onRestoreInstanceState(ss.getSuperState()); 1552 mDataChanged = true; 1553 1554 mSyncHeight = ss.height; 1555 1556 if (ss.selectedId >= 0) { 1557 mNeedSync = true; 1558 mSyncRowId = ss.selectedId; 1559 mSyncPosition = ss.position; 1560 mSpecificTop = ss.viewTop; 1561 mSyncMode = SYNC_SELECTED_POSITION; 1562 } else if (ss.firstId >= 0) { 1563 setSelectedPositionInt(INVALID_POSITION); 1564 // Do this before setting mNeedSync since setNextSelectedPosition looks at mNeedSync 1565 setNextSelectedPositionInt(INVALID_POSITION); 1566 mSelectorPosition = INVALID_POSITION; 1567 mNeedSync = true; 1568 mSyncRowId = ss.firstId; 1569 mSyncPosition = ss.position; 1570 mSpecificTop = ss.viewTop; 1571 mSyncMode = SYNC_FIRST_POSITION; 1572 } 1573 1574 setFilterText(ss.filter); 1575 1576 if (ss.checkState != null) { 1577 mCheckStates = ss.checkState; 1578 } 1579 1580 if (ss.checkIdState != null) { 1581 mCheckedIdStates = ss.checkIdState; 1582 } 1583 1584 mCheckedItemCount = ss.checkedItemCount; 1585 1586 if (ss.inActionMode && mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL && 1587 mMultiChoiceModeCallback != null) { 1588 mChoiceActionMode = startActionMode(mMultiChoiceModeCallback); 1589 } 1590 1591 requestLayout(); 1592 } 1593 1594 private boolean acceptFilter() { 1595 return mTextFilterEnabled && getAdapter() instanceof Filterable && 1596 ((Filterable) getAdapter()).getFilter() != null; 1597 } 1598 1599 /** 1600 * Sets the initial value for the text filter. 1601 * @param filterText The text to use for the filter. 1602 * 1603 * @see #setTextFilterEnabled 1604 */ 1605 public void setFilterText(String filterText) { 1606 // TODO: Should we check for acceptFilter()? 1607 if (mTextFilterEnabled && !TextUtils.isEmpty(filterText)) { 1608 createTextFilter(false); 1609 // This is going to call our listener onTextChanged, but we might not 1610 // be ready to bring up a window yet 1611 mTextFilter.setText(filterText); 1612 mTextFilter.setSelection(filterText.length()); 1613 if (mAdapter instanceof Filterable) { 1614 // if mPopup is non-null, then onTextChanged will do the filtering 1615 if (mPopup == null) { 1616 Filter f = ((Filterable) mAdapter).getFilter(); 1617 f.filter(filterText); 1618 } 1619 // Set filtered to true so we will display the filter window when our main 1620 // window is ready 1621 mFiltered = true; 1622 mDataSetObserver.clearSavedState(); 1623 } 1624 } 1625 } 1626 1627 /** 1628 * Returns the list's text filter, if available. 1629 * @return the list's text filter or null if filtering isn't enabled 1630 */ 1631 public CharSequence getTextFilter() { 1632 if (mTextFilterEnabled && mTextFilter != null) { 1633 return mTextFilter.getText(); 1634 } 1635 return null; 1636 } 1637 1638 @Override 1639 protected void onFocusChanged(boolean gainFocus, int direction, Rect previouslyFocusedRect) { 1640 super.onFocusChanged(gainFocus, direction, previouslyFocusedRect); 1641 if (gainFocus && mSelectedPosition < 0 && !isInTouchMode()) { 1642 resurrectSelection(); 1643 } 1644 } 1645 1646 @Override 1647 public void requestLayout() { 1648 if (!mBlockLayoutRequests && !mInLayout) { 1649 super.requestLayout(); 1650 } 1651 } 1652 1653 /** 1654 * The list is empty. Clear everything out. 1655 */ 1656 void resetList() { 1657 removeAllViewsInLayout(); 1658 mFirstPosition = 0; 1659 mDataChanged = false; 1660 mNeedSync = false; 1661 mOldSelectedPosition = INVALID_POSITION; 1662 mOldSelectedRowId = INVALID_ROW_ID; 1663 setSelectedPositionInt(INVALID_POSITION); 1664 setNextSelectedPositionInt(INVALID_POSITION); 1665 mSelectedTop = 0; 1666 mSelectorPosition = INVALID_POSITION; 1667 mSelectorRect.setEmpty(); 1668 invalidate(); 1669 } 1670 1671 @Override 1672 protected int computeVerticalScrollExtent() { 1673 final int count = getChildCount(); 1674 if (count > 0) { 1675 if (mSmoothScrollbarEnabled) { 1676 int extent = count * 100; 1677 1678 View view = getChildAt(0); 1679 final int top = view.getTop(); 1680 int height = view.getHeight(); 1681 if (height > 0) { 1682 extent += (top * 100) / height; 1683 } 1684 1685 view = getChildAt(count - 1); 1686 final int bottom = view.getBottom(); 1687 height = view.getHeight(); 1688 if (height > 0) { 1689 extent -= ((bottom - getHeight()) * 100) / height; 1690 } 1691 1692 return extent; 1693 } else { 1694 return 1; 1695 } 1696 } 1697 return 0; 1698 } 1699 1700 @Override 1701 protected int computeVerticalScrollOffset() { 1702 final int firstPosition = mFirstPosition; 1703 final int childCount = getChildCount(); 1704 if (firstPosition >= 0 && childCount > 0) { 1705 if (mSmoothScrollbarEnabled) { 1706 final View view = getChildAt(0); 1707 final int top = view.getTop(); 1708 int height = view.getHeight(); 1709 if (height > 0) { 1710 return Math.max(firstPosition * 100 - (top * 100) / height + 1711 (int)((float)mScrollY / getHeight() * mItemCount * 100), 0); 1712 } 1713 } else { 1714 int index; 1715 final int count = mItemCount; 1716 if (firstPosition == 0) { 1717 index = 0; 1718 } else if (firstPosition + childCount == count) { 1719 index = count; 1720 } else { 1721 index = firstPosition + childCount / 2; 1722 } 1723 return (int) (firstPosition + childCount * (index / (float) count)); 1724 } 1725 } 1726 return 0; 1727 } 1728 1729 @Override 1730 protected int computeVerticalScrollRange() { 1731 int result; 1732 if (mSmoothScrollbarEnabled) { 1733 result = Math.max(mItemCount * 100, 0); 1734 if (mScrollY != 0) { 1735 // Compensate for overscroll 1736 result += Math.abs((int) ((float) mScrollY / getHeight() * mItemCount * 100)); 1737 } 1738 } else { 1739 result = mItemCount; 1740 } 1741 return result; 1742 } 1743 1744 @Override 1745 protected float getTopFadingEdgeStrength() { 1746 final int count = getChildCount(); 1747 final float fadeEdge = super.getTopFadingEdgeStrength(); 1748 if (count == 0) { 1749 return fadeEdge; 1750 } else { 1751 if (mFirstPosition > 0) { 1752 return 1.0f; 1753 } 1754 1755 final int top = getChildAt(0).getTop(); 1756 final float fadeLength = (float) getVerticalFadingEdgeLength(); 1757 return top < mPaddingTop ? (float) -(top - mPaddingTop) / fadeLength : fadeEdge; 1758 } 1759 } 1760 1761 @Override 1762 protected float getBottomFadingEdgeStrength() { 1763 final int count = getChildCount(); 1764 final float fadeEdge = super.getBottomFadingEdgeStrength(); 1765 if (count == 0) { 1766 return fadeEdge; 1767 } else { 1768 if (mFirstPosition + count - 1 < mItemCount - 1) { 1769 return 1.0f; 1770 } 1771 1772 final int bottom = getChildAt(count - 1).getBottom(); 1773 final int height = getHeight(); 1774 final float fadeLength = (float) getVerticalFadingEdgeLength(); 1775 return bottom > height - mPaddingBottom ? 1776 (float) (bottom - height + mPaddingBottom) / fadeLength : fadeEdge; 1777 } 1778 } 1779 1780 @Override 1781 protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { 1782 if (mSelector == null) { 1783 useDefaultSelector(); 1784 } 1785 final Rect listPadding = mListPadding; 1786 listPadding.left = mSelectionLeftPadding + mPaddingLeft; 1787 listPadding.top = mSelectionTopPadding + mPaddingTop; 1788 listPadding.right = mSelectionRightPadding + mPaddingRight; 1789 listPadding.bottom = mSelectionBottomPadding + mPaddingBottom; 1790 1791 // Check if our previous measured size was at a point where we should scroll later. 1792 if (mTranscriptMode == TRANSCRIPT_MODE_NORMAL) { 1793 final int childCount = getChildCount(); 1794 final int listBottom = getBottom() - getPaddingBottom(); 1795 final View lastChild = getChildAt(childCount - 1); 1796 final int lastBottom = lastChild != null ? lastChild.getBottom() : listBottom; 1797 mForceTranscriptScroll = mFirstPosition + childCount >= mOldItemCount && 1798 lastBottom <= listBottom; 1799 } 1800 } 1801 1802 /** 1803 * Subclasses should NOT override this method but 1804 * {@link #layoutChildren()} instead. 1805 */ 1806 @Override 1807 protected void onLayout(boolean changed, int l, int t, int r, int b) { 1808 super.onLayout(changed, l, t, r, b); 1809 mInLayout = true; 1810 if (changed) { 1811 int childCount = getChildCount(); 1812 for (int i = 0; i < childCount; i++) { 1813 getChildAt(i).forceLayout(); 1814 } 1815 mRecycler.markChildrenDirty(); 1816 } 1817 1818 if (mFastScroller != null && mItemCount != mOldItemCount) { 1819 mFastScroller.onItemCountChanged(mOldItemCount, mItemCount); 1820 } 1821 1822 layoutChildren(); 1823 mInLayout = false; 1824 1825 mOverscrollMax = (b - t) / OVERSCROLL_LIMIT_DIVISOR; 1826 } 1827 1828 /** 1829 * @hide 1830 */ 1831 @Override 1832 protected boolean setFrame(int left, int top, int right, int bottom) { 1833 final boolean changed = super.setFrame(left, top, right, bottom); 1834 1835 if (changed) { 1836 // Reposition the popup when the frame has changed. This includes 1837 // translating the widget, not just changing its dimension. The 1838 // filter popup needs to follow the widget. 1839 final boolean visible = getWindowVisibility() == View.VISIBLE; 1840 if (mFiltered && visible && mPopup != null && mPopup.isShowing()) { 1841 positionPopup(); 1842 } 1843 } 1844 1845 return changed; 1846 } 1847 1848 /** 1849 * Subclasses must override this method to layout their children. 1850 */ 1851 protected void layoutChildren() { 1852 } 1853 1854 void updateScrollIndicators() { 1855 if (mScrollUp != null) { 1856 boolean canScrollUp; 1857 // 0th element is not visible 1858 canScrollUp = mFirstPosition > 0; 1859 1860 // ... Or top of 0th element is not visible 1861 if (!canScrollUp) { 1862 if (getChildCount() > 0) { 1863 View child = getChildAt(0); 1864 canScrollUp = child.getTop() < mListPadding.top; 1865 } 1866 } 1867 1868 mScrollUp.setVisibility(canScrollUp ? View.VISIBLE : View.INVISIBLE); 1869 } 1870 1871 if (mScrollDown != null) { 1872 boolean canScrollDown; 1873 int count = getChildCount(); 1874 1875 // Last item is not visible 1876 canScrollDown = (mFirstPosition + count) < mItemCount; 1877 1878 // ... Or bottom of the last element is not visible 1879 if (!canScrollDown && count > 0) { 1880 View child = getChildAt(count - 1); 1881 canScrollDown = child.getBottom() > mBottom - mListPadding.bottom; 1882 } 1883 1884 mScrollDown.setVisibility(canScrollDown ? View.VISIBLE : View.INVISIBLE); 1885 } 1886 } 1887 1888 @Override 1889 @ViewDebug.ExportedProperty 1890 public View getSelectedView() { 1891 if (mItemCount > 0 && mSelectedPosition >= 0) { 1892 return getChildAt(mSelectedPosition - mFirstPosition); 1893 } else { 1894 return null; 1895 } 1896 } 1897 1898 /** 1899 * List padding is the maximum of the normal view's padding and the padding of the selector. 1900 * 1901 * @see android.view.View#getPaddingTop() 1902 * @see #getSelector() 1903 * 1904 * @return The top list padding. 1905 */ 1906 public int getListPaddingTop() { 1907 return mListPadding.top; 1908 } 1909 1910 /** 1911 * List padding is the maximum of the normal view's padding and the padding of the selector. 1912 * 1913 * @see android.view.View#getPaddingBottom() 1914 * @see #getSelector() 1915 * 1916 * @return The bottom list padding. 1917 */ 1918 public int getListPaddingBottom() { 1919 return mListPadding.bottom; 1920 } 1921 1922 /** 1923 * List padding is the maximum of the normal view's padding and the padding of the selector. 1924 * 1925 * @see android.view.View#getPaddingLeft() 1926 * @see #getSelector() 1927 * 1928 * @return The left list padding. 1929 */ 1930 public int getListPaddingLeft() { 1931 return mListPadding.left; 1932 } 1933 1934 /** 1935 * List padding is the maximum of the normal view's padding and the padding of the selector. 1936 * 1937 * @see android.view.View#getPaddingRight() 1938 * @see #getSelector() 1939 * 1940 * @return The right list padding. 1941 */ 1942 public int getListPaddingRight() { 1943 return mListPadding.right; 1944 } 1945 1946 /** 1947 * Get a view and have it show the data associated with the specified 1948 * position. This is called when we have already discovered that the view is 1949 * not available for reuse in the recycle bin. The only choices left are 1950 * converting an old view or making a new one. 1951 * 1952 * @param position The position to display 1953 * @param isScrap Array of at least 1 boolean, the first entry will become true if 1954 * the returned view was taken from the scrap heap, false if otherwise. 1955 * 1956 * @return A view displaying the data associated with the specified position 1957 */ 1958 View obtainView(int position, boolean[] isScrap) { 1959 isScrap[0] = false; 1960 View scrapView; 1961 1962 scrapView = mRecycler.getScrapView(position); 1963 1964 View child; 1965 if (scrapView != null) { 1966 if (ViewDebug.TRACE_RECYCLER) { 1967 ViewDebug.trace(scrapView, ViewDebug.RecyclerTraceType.RECYCLE_FROM_SCRAP_HEAP, 1968 position, -1); 1969 } 1970 1971 child = mAdapter.getView(position, scrapView, this); 1972 1973 if (ViewDebug.TRACE_RECYCLER) { 1974 ViewDebug.trace(child, ViewDebug.RecyclerTraceType.BIND_VIEW, 1975 position, getChildCount()); 1976 } 1977 1978 if (child != scrapView) { 1979 mRecycler.addScrapView(scrapView, position); 1980 if (mCacheColorHint != 0) { 1981 child.setDrawingCacheBackgroundColor(mCacheColorHint); 1982 } 1983 if (ViewDebug.TRACE_RECYCLER) { 1984 ViewDebug.trace(scrapView, ViewDebug.RecyclerTraceType.MOVE_TO_SCRAP_HEAP, 1985 position, -1); 1986 } 1987 } else { 1988 isScrap[0] = true; 1989 child.dispatchFinishTemporaryDetach(); 1990 } 1991 } else { 1992 child = mAdapter.getView(position, null, this); 1993 if (mCacheColorHint != 0) { 1994 child.setDrawingCacheBackgroundColor(mCacheColorHint); 1995 } 1996 if (ViewDebug.TRACE_RECYCLER) { 1997 ViewDebug.trace(child, ViewDebug.RecyclerTraceType.NEW_VIEW, 1998 position, getChildCount()); 1999 } 2000 } 2001 2002 return child; 2003 } 2004 2005 void positionSelector(int position, View sel) { 2006 if (position != INVALID_POSITION) { 2007 mSelectorPosition = position; 2008 } 2009 2010 final Rect selectorRect = mSelectorRect; 2011 selectorRect.set(sel.getLeft(), sel.getTop(), sel.getRight(), sel.getBottom()); 2012 if (sel instanceof SelectionBoundsAdjuster) { 2013 ((SelectionBoundsAdjuster)sel).adjustListItemSelectionBounds(selectorRect); 2014 } 2015 positionSelector(selectorRect.left, selectorRect.top, selectorRect.right, 2016 selectorRect.bottom); 2017 2018 final boolean isChildViewEnabled = mIsChildViewEnabled; 2019 if (sel.isEnabled() != isChildViewEnabled) { 2020 mIsChildViewEnabled = !isChildViewEnabled; 2021 if (getSelectedItemPosition() != INVALID_POSITION) { 2022 refreshDrawableState(); 2023 } 2024 } 2025 } 2026 2027 private void positionSelector(int l, int t, int r, int b) { 2028 mSelectorRect.set(l - mSelectionLeftPadding, t - mSelectionTopPadding, r 2029 + mSelectionRightPadding, b + mSelectionBottomPadding); 2030 } 2031 2032 @Override 2033 protected void dispatchDraw(Canvas canvas) { 2034 int saveCount = 0; 2035 final boolean clipToPadding = (mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK; 2036 if (clipToPadding) { 2037 saveCount = canvas.save(); 2038 final int scrollX = mScrollX; 2039 final int scrollY = mScrollY; 2040 canvas.clipRect(scrollX + mPaddingLeft, scrollY + mPaddingTop, 2041 scrollX + mRight - mLeft - mPaddingRight, 2042 scrollY + mBottom - mTop - mPaddingBottom); 2043 mGroupFlags &= ~CLIP_TO_PADDING_MASK; 2044 } 2045 2046 final boolean drawSelectorOnTop = mDrawSelectorOnTop; 2047 if (!drawSelectorOnTop) { 2048 drawSelector(canvas); 2049 } 2050 2051 super.dispatchDraw(canvas); 2052 2053 if (drawSelectorOnTop) { 2054 drawSelector(canvas); 2055 } 2056 2057 if (clipToPadding) { 2058 canvas.restoreToCount(saveCount); 2059 mGroupFlags |= CLIP_TO_PADDING_MASK; 2060 } 2061 } 2062 2063 @Override 2064 protected boolean isPaddingOffsetRequired() { 2065 return (mGroupFlags & CLIP_TO_PADDING_MASK) != CLIP_TO_PADDING_MASK; 2066 } 2067 2068 @Override 2069 protected int getLeftPaddingOffset() { 2070 return (mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK ? 0 : -mPaddingLeft; 2071 } 2072 2073 @Override 2074 protected int getTopPaddingOffset() { 2075 return (mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK ? 0 : -mPaddingTop; 2076 } 2077 2078 @Override 2079 protected int getRightPaddingOffset() { 2080 return (mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK ? 0 : mPaddingRight; 2081 } 2082 2083 @Override 2084 protected int getBottomPaddingOffset() { 2085 return (mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK ? 0 : mPaddingBottom; 2086 } 2087 2088 @Override 2089 protected void onSizeChanged(int w, int h, int oldw, int oldh) { 2090 if (getChildCount() > 0) { 2091 mDataChanged = true; 2092 rememberSyncState(); 2093 } 2094 2095 if (mFastScroller != null) { 2096 mFastScroller.onSizeChanged(w, h, oldw, oldh); 2097 } 2098 } 2099 2100 /** 2101 * @return True if the current touch mode requires that we draw the selector in the pressed 2102 * state. 2103 */ 2104 boolean touchModeDrawsInPressedState() { 2105 // FIXME use isPressed for this 2106 switch (mTouchMode) { 2107 case TOUCH_MODE_TAP: 2108 case TOUCH_MODE_DONE_WAITING: 2109 return true; 2110 default: 2111 return false; 2112 } 2113 } 2114 2115 /** 2116 * Indicates whether this view is in a state where the selector should be drawn. This will 2117 * happen if we have focus but are not in touch mode, or we are in the middle of displaying 2118 * the pressed state for an item. 2119 * 2120 * @return True if the selector should be shown 2121 */ 2122 boolean shouldShowSelector() { 2123 return (hasFocus() && !isInTouchMode()) || touchModeDrawsInPressedState(); 2124 } 2125 2126 private void drawSelector(Canvas canvas) { 2127 if (!mSelectorRect.isEmpty()) { 2128 final Drawable selector = mSelector; 2129 selector.setBounds(mSelectorRect); 2130 selector.draw(canvas); 2131 } 2132 } 2133 2134 /** 2135 * Controls whether the selection highlight drawable should be drawn on top of the item or 2136 * behind it. 2137 * 2138 * @param onTop If true, the selector will be drawn on the item it is highlighting. The default 2139 * is false. 2140 * 2141 * @attr ref android.R.styleable#AbsListView_drawSelectorOnTop 2142 */ 2143 public void setDrawSelectorOnTop(boolean onTop) { 2144 mDrawSelectorOnTop = onTop; 2145 } 2146 2147 /** 2148 * Set a Drawable that should be used to highlight the currently selected item. 2149 * 2150 * @param resID A Drawable resource to use as the selection highlight. 2151 * 2152 * @attr ref android.R.styleable#AbsListView_listSelector 2153 */ 2154 public void setSelector(int resID) { 2155 setSelector(getResources().getDrawable(resID)); 2156 } 2157 2158 public void setSelector(Drawable sel) { 2159 if (mSelector != null) { 2160 mSelector.setCallback(null); 2161 unscheduleDrawable(mSelector); 2162 } 2163 mSelector = sel; 2164 Rect padding = new Rect(); 2165 sel.getPadding(padding); 2166 mSelectionLeftPadding = padding.left; 2167 mSelectionTopPadding = padding.top; 2168 mSelectionRightPadding = padding.right; 2169 mSelectionBottomPadding = padding.bottom; 2170 sel.setCallback(this); 2171 updateSelectorState(); 2172 } 2173 2174 /** 2175 * Returns the selector {@link android.graphics.drawable.Drawable} that is used to draw the 2176 * selection in the list. 2177 * 2178 * @return the drawable used to display the selector 2179 */ 2180 public Drawable getSelector() { 2181 return mSelector; 2182 } 2183 2184 /** 2185 * Sets the selector state to "pressed" and posts a CheckForKeyLongPress to see if 2186 * this is a long press. 2187 */ 2188 void keyPressed() { 2189 if (!isEnabled() || !isClickable()) { 2190 return; 2191 } 2192 2193 Drawable selector = mSelector; 2194 Rect selectorRect = mSelectorRect; 2195 if (selector != null && (isFocused() || touchModeDrawsInPressedState()) 2196 && !selectorRect.isEmpty()) { 2197 2198 final View v = getChildAt(mSelectedPosition - mFirstPosition); 2199 2200 if (v != null) { 2201 if (v.hasFocusable()) return; 2202 v.setPressed(true); 2203 } 2204 setPressed(true); 2205 2206 final boolean longClickable = isLongClickable(); 2207 Drawable d = selector.getCurrent(); 2208 if (d != null && d instanceof TransitionDrawable) { 2209 if (longClickable) { 2210 ((TransitionDrawable) d).startTransition( 2211 ViewConfiguration.getLongPressTimeout()); 2212 } else { 2213 ((TransitionDrawable) d).resetTransition(); 2214 } 2215 } 2216 if (longClickable && !mDataChanged) { 2217 if (mPendingCheckForKeyLongPress == null) { 2218 mPendingCheckForKeyLongPress = new CheckForKeyLongPress(); 2219 } 2220 mPendingCheckForKeyLongPress.rememberWindowAttachCount(); 2221 postDelayed(mPendingCheckForKeyLongPress, ViewConfiguration.getLongPressTimeout()); 2222 } 2223 } 2224 } 2225 2226 public void setScrollIndicators(View up, View down) { 2227 mScrollUp = up; 2228 mScrollDown = down; 2229 } 2230 2231 void updateSelectorState() { 2232 if (mSelector != null) { 2233 if (shouldShowSelector()) { 2234 mSelector.setState(getDrawableState()); 2235 } else { 2236 mSelector.setState(StateSet.NOTHING); 2237 } 2238 } 2239 } 2240 2241 @Override 2242 protected void drawableStateChanged() { 2243 super.drawableStateChanged(); 2244 updateSelectorState(); 2245 } 2246 2247 @Override 2248 protected int[] onCreateDrawableState(int extraSpace) { 2249 // If the child view is enabled then do the default behavior. 2250 if (mIsChildViewEnabled) { 2251 // Common case 2252 return super.onCreateDrawableState(extraSpace); 2253 } 2254 2255 // The selector uses this View's drawable state. The selected child view 2256 // is disabled, so we need to remove the enabled state from the drawable 2257 // states. 2258 final int enabledState = ENABLED_STATE_SET[0]; 2259 2260 // If we don't have any extra space, it will return one of the static state arrays, 2261 // and clearing the enabled state on those arrays is a bad thing! If we specify 2262 // we need extra space, it will create+copy into a new array that safely mutable. 2263 int[] state = super.onCreateDrawableState(extraSpace + 1); 2264 int enabledPos = -1; 2265 for (int i = state.length - 1; i >= 0; i--) { 2266 if (state[i] == enabledState) { 2267 enabledPos = i; 2268 break; 2269 } 2270 } 2271 2272 // Remove the enabled state 2273 if (enabledPos >= 0) { 2274 System.arraycopy(state, enabledPos + 1, state, enabledPos, 2275 state.length - enabledPos - 1); 2276 } 2277 2278 return state; 2279 } 2280 2281 @Override 2282 public boolean verifyDrawable(Drawable dr) { 2283 return mSelector == dr || super.verifyDrawable(dr); 2284 } 2285 2286 @Override 2287 public void jumpDrawablesToCurrentState() { 2288 super.jumpDrawablesToCurrentState(); 2289 if (mSelector != null) mSelector.jumpToCurrentState(); 2290 } 2291 2292 @Override 2293 protected void onAttachedToWindow() { 2294 super.onAttachedToWindow(); 2295 2296 final ViewTreeObserver treeObserver = getViewTreeObserver(); 2297 treeObserver.addOnTouchModeChangeListener(this); 2298 if (mTextFilterEnabled && mPopup != null && !mGlobalLayoutListenerAddedFilter) { 2299 treeObserver.addOnGlobalLayoutListener(this); 2300 } 2301 2302 if (mAdapter != null && mDataSetObserver == null) { 2303 mDataSetObserver = new AdapterDataSetObserver(); 2304 mAdapter.registerDataSetObserver(mDataSetObserver); 2305 2306 // Data may have changed while we were detached. Refresh. 2307 mDataChanged = true; 2308 mOldItemCount = mItemCount; 2309 mItemCount = mAdapter.getCount(); 2310 } 2311 } 2312 2313 @Override 2314 protected void onDetachedFromWindow() { 2315 super.onDetachedFromWindow(); 2316 2317 // Dismiss the popup in case onSaveInstanceState() was not invoked 2318 dismissPopup(); 2319 2320 // Detach any view left in the scrap heap 2321 mRecycler.clear(); 2322 2323 final ViewTreeObserver treeObserver = getViewTreeObserver(); 2324 treeObserver.removeOnTouchModeChangeListener(this); 2325 if (mTextFilterEnabled && mPopup != null) { 2326 treeObserver.removeGlobalOnLayoutListener(this); 2327 mGlobalLayoutListenerAddedFilter = false; 2328 } 2329 2330 if (mAdapter != null) { 2331 mAdapter.unregisterDataSetObserver(mDataSetObserver); 2332 mDataSetObserver = null; 2333 } 2334 2335 if (mScrollStrictSpan != null) { 2336 mScrollStrictSpan.finish(); 2337 mScrollStrictSpan = null; 2338 } 2339 2340 if (mFlingStrictSpan != null) { 2341 mFlingStrictSpan.finish(); 2342 mFlingStrictSpan = null; 2343 } 2344 2345 if (mFlingRunnable != null) { 2346 removeCallbacks(mFlingRunnable); 2347 } 2348 2349 if (mPositionScroller != null) { 2350 mPositionScroller.stop(); 2351 } 2352 2353 if (mClearScrollingCache != null) { 2354 removeCallbacks(mClearScrollingCache); 2355 } 2356 2357 if (mPerformClick != null) { 2358 removeCallbacks(mPerformClick); 2359 } 2360 2361 if (mTouchModeReset != null) { 2362 removeCallbacks(mTouchModeReset); 2363 mTouchModeReset = null; 2364 } 2365 } 2366 2367 @Override 2368 public void onWindowFocusChanged(boolean hasWindowFocus) { 2369 super.onWindowFocusChanged(hasWindowFocus); 2370 2371 final int touchMode = isInTouchMode() ? TOUCH_MODE_ON : TOUCH_MODE_OFF; 2372 2373 if (!hasWindowFocus) { 2374 setChildrenDrawingCacheEnabled(false); 2375 if (mFlingRunnable != null) { 2376 removeCallbacks(mFlingRunnable); 2377 // let the fling runnable report it's new state which 2378 // should be idle 2379 mFlingRunnable.endFling(); 2380 if (mPositionScroller != null) { 2381 mPositionScroller.stop(); 2382 } 2383 if (mScrollY != 0) { 2384 mScrollY = 0; 2385 invalidateParentCaches(); 2386 finishGlows(); 2387 invalidate(); 2388 } 2389 } 2390 // Always hide the type filter 2391 dismissPopup(); 2392 2393 if (touchMode == TOUCH_MODE_OFF) { 2394 // Remember the last selected element 2395 mResurrectToPosition = mSelectedPosition; 2396 } 2397 } else { 2398 if (mFiltered && !mPopupHidden) { 2399 // Show the type filter only if a filter is in effect 2400 showPopup(); 2401 } 2402 2403 // If we changed touch mode since the last time we had focus 2404 if (touchMode != mLastTouchMode && mLastTouchMode != TOUCH_MODE_UNKNOWN) { 2405 // If we come back in trackball mode, we bring the selection back 2406 if (touchMode == TOUCH_MODE_OFF) { 2407 // This will trigger a layout 2408 resurrectSelection(); 2409 2410 // If we come back in touch mode, then we want to hide the selector 2411 } else { 2412 hideSelector(); 2413 mLayoutMode = LAYOUT_NORMAL; 2414 layoutChildren(); 2415 } 2416 } 2417 } 2418 2419 mLastTouchMode = touchMode; 2420 } 2421 2422 /** 2423 * Creates the ContextMenuInfo returned from {@link #getContextMenuInfo()}. This 2424 * methods knows the view, position and ID of the item that received the 2425 * long press. 2426 * 2427 * @param view The view that received the long press. 2428 * @param position The position of the item that received the long press. 2429 * @param id The ID of the item that received the long press. 2430 * @return The extra information that should be returned by 2431 * {@link #getContextMenuInfo()}. 2432 */ 2433 ContextMenuInfo createContextMenuInfo(View view, int position, long id) { 2434 return new AdapterContextMenuInfo(view, position, id); 2435 } 2436 2437 /** 2438 * A base class for Runnables that will check that their view is still attached to 2439 * the original window as when the Runnable was created. 2440 * 2441 */ 2442 private class WindowRunnnable { 2443 private int mOriginalAttachCount; 2444 2445 public void rememberWindowAttachCount() { 2446 mOriginalAttachCount = getWindowAttachCount(); 2447 } 2448 2449 public boolean sameWindow() { 2450 return hasWindowFocus() && getWindowAttachCount() == mOriginalAttachCount; 2451 } 2452 } 2453 2454 private class PerformClick extends WindowRunnnable implements Runnable { 2455 int mClickMotionPosition; 2456 2457 public void run() { 2458 // The data has changed since we posted this action in the event queue, 2459 // bail out before bad things happen 2460 if (mDataChanged) return; 2461 2462 final ListAdapter adapter = mAdapter; 2463 final int motionPosition = mClickMotionPosition; 2464 if (adapter != null && mItemCount > 0 && 2465 motionPosition != INVALID_POSITION && 2466 motionPosition < adapter.getCount() && sameWindow()) { 2467 final View view = getChildAt(motionPosition - mFirstPosition); 2468 // If there is no view, something bad happened (the view scrolled off the 2469 // screen, etc.) and we should cancel the click 2470 if (view != null) { 2471 performItemClick(view, motionPosition, adapter.getItemId(motionPosition)); 2472 } 2473 } 2474 } 2475 } 2476 2477 private class CheckForLongPress extends WindowRunnnable implements Runnable { 2478 public void run() { 2479 final int motionPosition = mMotionPosition; 2480 final View child = getChildAt(motionPosition - mFirstPosition); 2481 if (child != null) { 2482 final int longPressPosition = mMotionPosition; 2483 final long longPressId = mAdapter.getItemId(mMotionPosition); 2484 2485 boolean handled = false; 2486 if (sameWindow() && !mDataChanged) { 2487 handled = performLongPress(child, longPressPosition, longPressId); 2488 } 2489 if (handled) { 2490 mTouchMode = TOUCH_MODE_REST; 2491 setPressed(false); 2492 child.setPressed(false); 2493 } else { 2494 mTouchMode = TOUCH_MODE_DONE_WAITING; 2495 } 2496 } 2497 } 2498 } 2499 2500 private class CheckForKeyLongPress extends WindowRunnnable implements Runnable { 2501 public void run() { 2502 if (isPressed() && mSelectedPosition >= 0) { 2503 int index = mSelectedPosition - mFirstPosition; 2504 View v = getChildAt(index); 2505 2506 if (!mDataChanged) { 2507 boolean handled = false; 2508 if (sameWindow()) { 2509 handled = performLongPress(v, mSelectedPosition, mSelectedRowId); 2510 } 2511 if (handled) { 2512 setPressed(false); 2513 v.setPressed(false); 2514 } 2515 } else { 2516 setPressed(false); 2517 if (v != null) v.setPressed(false); 2518 } 2519 } 2520 } 2521 } 2522 2523 boolean performLongPress(final View child, 2524 final int longPressPosition, final long longPressId) { 2525 // CHOICE_MODE_MULTIPLE_MODAL takes over long press. 2526 if (mChoiceMode == CHOICE_MODE_MULTIPLE_MODAL) { 2527 if (mChoiceActionMode == null) { 2528 mChoiceActionMode = startActionMode(mMultiChoiceModeCallback); 2529 setItemChecked(longPressPosition, true); 2530 } 2531 // TODO Should we select the long pressed item if we were already in 2532 // selection mode? (i.e. treat it like an item click?) 2533 performHapticFeedback(HapticFeedbackConstants.LONG_PRESS); 2534 return true; 2535 } 2536 2537 boolean handled = false; 2538 if (mOnItemLongClickListener != null) { 2539 handled = mOnItemLongClickListener.onItemLongClick(AbsListView.this, child, 2540 longPressPosition, longPressId); 2541 } 2542 if (!handled) { 2543 mContextMenuInfo = createContextMenuInfo(child, longPressPosition, longPressId); 2544 handled = super.showContextMenuForChild(AbsListView.this); 2545 } 2546 if (handled) { 2547 performHapticFeedback(HapticFeedbackConstants.LONG_PRESS); 2548 } 2549 return handled; 2550 } 2551 2552 @Override 2553 protected ContextMenuInfo getContextMenuInfo() { 2554 return mContextMenuInfo; 2555 } 2556 2557 /** @hide */ 2558 @Override 2559 public boolean showContextMenu(float x, float y, int metaState) { 2560 final int position = pointToPosition((int)x, (int)y); 2561 if (position != INVALID_POSITION) { 2562 final long id = mAdapter.getItemId(position); 2563 View child = getChildAt(position - mFirstPosition); 2564 if (child != null) { 2565 mContextMenuInfo = createContextMenuInfo(child, position, id); 2566 return super.showContextMenuForChild(AbsListView.this); 2567 } 2568 } 2569 return super.showContextMenu(x, y, metaState); 2570 } 2571 2572 @Override 2573 public boolean showContextMenuForChild(View originalView) { 2574 final int longPressPosition = getPositionForView(originalView); 2575 if (longPressPosition >= 0) { 2576 final long longPressId = mAdapter.getItemId(longPressPosition); 2577 boolean handled = false; 2578 2579 if (mOnItemLongClickListener != null) { 2580 handled = mOnItemLongClickListener.onItemLongClick(AbsListView.this, originalView, 2581 longPressPosition, longPressId); 2582 } 2583 if (!handled) { 2584 mContextMenuInfo = createContextMenuInfo( 2585 getChildAt(longPressPosition - mFirstPosition), 2586 longPressPosition, longPressId); 2587 handled = super.showContextMenuForChild(originalView); 2588 } 2589 2590 return handled; 2591 } 2592 return false; 2593 } 2594 2595 @Override 2596 public boolean onKeyDown(int keyCode, KeyEvent event) { 2597 return false; 2598 } 2599 2600 @Override 2601 public boolean onKeyUp(int keyCode, KeyEvent event) { 2602 switch (keyCode) { 2603 case KeyEvent.KEYCODE_DPAD_CENTER: 2604 case KeyEvent.KEYCODE_ENTER: 2605 if (!isEnabled()) { 2606 return true; 2607 } 2608 if (isClickable() && isPressed() && 2609 mSelectedPosition >= 0 && mAdapter != null && 2610 mSelectedPosition < mAdapter.getCount()) { 2611 2612 final View view = getChildAt(mSelectedPosition - mFirstPosition); 2613 if (view != null) { 2614 performItemClick(view, mSelectedPosition, mSelectedRowId); 2615 view.setPressed(false); 2616 } 2617 setPressed(false); 2618 return true; 2619 } 2620 break; 2621 } 2622 return super.onKeyUp(keyCode, event); 2623 } 2624 2625 @Override 2626 protected void dispatchSetPressed(boolean pressed) { 2627 // Don't dispatch setPressed to our children. We call setPressed on ourselves to 2628 // get the selector in the right state, but we don't want to press each child. 2629 } 2630 2631 /** 2632 * Maps a point to a position in the list. 2633 * 2634 * @param x X in local coordinate 2635 * @param y Y in local coordinate 2636 * @return The position of the item which contains the specified point, or 2637 * {@link #INVALID_POSITION} if the point does not intersect an item. 2638 */ 2639 public int pointToPosition(int x, int y) { 2640 Rect frame = mTouchFrame; 2641 if (frame == null) { 2642 mTouchFrame = new Rect(); 2643 frame = mTouchFrame; 2644 } 2645 2646 final int count = getChildCount(); 2647 for (int i = count - 1; i >= 0; i--) { 2648 final View child = getChildAt(i); 2649 if (child.getVisibility() == View.VISIBLE) { 2650 child.getHitRect(frame); 2651 if (frame.contains(x, y)) { 2652 return mFirstPosition + i; 2653 } 2654 } 2655 } 2656 return INVALID_POSITION; 2657 } 2658 2659 2660 /** 2661 * Maps a point to a the rowId of the item which intersects that point. 2662 * 2663 * @param x X in local coordinate 2664 * @param y Y in local coordinate 2665 * @return The rowId of the item which contains the specified point, or {@link #INVALID_ROW_ID} 2666 * if the point does not intersect an item. 2667 */ 2668 public long pointToRowId(int x, int y) { 2669 int position = pointToPosition(x, y); 2670 if (position >= 0) { 2671 return mAdapter.getItemId(position); 2672 } 2673 return INVALID_ROW_ID; 2674 } 2675 2676 final class CheckForTap implements Runnable { 2677 public void run() { 2678 if (mTouchMode == TOUCH_MODE_DOWN) { 2679 mTouchMode = TOUCH_MODE_TAP; 2680 final View child = getChildAt(mMotionPosition - mFirstPosition); 2681 if (child != null && !child.hasFocusable()) { 2682 mLayoutMode = LAYOUT_NORMAL; 2683 2684 if (!mDataChanged) { 2685 child.setPressed(true); 2686 setPressed(true); 2687 layoutChildren(); 2688 positionSelector(mMotionPosition, child); 2689 refreshDrawableState(); 2690 2691 final int longPressTimeout = ViewConfiguration.getLongPressTimeout(); 2692 final boolean longClickable = isLongClickable(); 2693 2694 if (mSelector != null) { 2695 Drawable d = mSelector.getCurrent(); 2696 if (d != null && d instanceof TransitionDrawable) { 2697 if (longClickable) { 2698 ((TransitionDrawable) d).startTransition(longPressTimeout); 2699 } else { 2700 ((TransitionDrawable) d).resetTransition(); 2701 } 2702 } 2703 } 2704 2705 if (longClickable) { 2706 if (mPendingCheckForLongPress == null) { 2707 mPendingCheckForLongPress = new CheckForLongPress(); 2708 } 2709 mPendingCheckForLongPress.rememberWindowAttachCount(); 2710 postDelayed(mPendingCheckForLongPress, longPressTimeout); 2711 } else { 2712 mTouchMode = TOUCH_MODE_DONE_WAITING; 2713 } 2714 } else { 2715 mTouchMode = TOUCH_MODE_DONE_WAITING; 2716 } 2717 } 2718 } 2719 } 2720 } 2721 2722 private boolean startScrollIfNeeded(int deltaY) { 2723 // Check if we have moved far enough that it looks more like a 2724 // scroll than a tap 2725 final int distance = Math.abs(deltaY); 2726 final boolean overscroll = mScrollY != 0; 2727 if (overscroll || distance > mTouchSlop) { 2728 createScrollingCache(); 2729 mTouchMode = overscroll ? TOUCH_MODE_OVERSCROLL : TOUCH_MODE_SCROLL; 2730 mMotionCorrection = deltaY; 2731 final Handler handler = getHandler(); 2732 // Handler should not be null unless the AbsListView is not attached to a 2733 // window, which would make it very hard to scroll it... but the monkeys 2734 // say it's possible. 2735 if (handler != null) { 2736 handler.removeCallbacks(mPendingCheckForLongPress); 2737 } 2738 setPressed(false); 2739 View motionView = getChildAt(mMotionPosition - mFirstPosition); 2740 if (motionView != null) { 2741 motionView.setPressed(false); 2742 } 2743 reportScrollStateChange(OnScrollListener.SCROLL_STATE_TOUCH_SCROLL); 2744 // Time to start stealing events! Once we've stolen them, don't let anyone 2745 // steal from us 2746 requestDisallowInterceptTouchEvent(true); 2747 return true; 2748 } 2749 2750 return false; 2751 } 2752 2753 public void onTouchModeChanged(boolean isInTouchMode) { 2754 if (isInTouchMode) { 2755 // Get rid of the selection when we enter touch mode 2756 hideSelector(); 2757 // Layout, but only if we already have done so previously. 2758 // (Otherwise may clobber a LAYOUT_SYNC layout that was requested to restore 2759 // state.) 2760 if (getHeight() > 0 && getChildCount() > 0) { 2761 // We do not lose focus initiating a touch (since AbsListView is focusable in 2762 // touch mode). Force an initial layout to get rid of the selection. 2763 layoutChildren(); 2764 } 2765 updateSelectorState(); 2766 } else { 2767 int touchMode = mTouchMode; 2768 if (touchMode == TOUCH_MODE_OVERSCROLL || touchMode == TOUCH_MODE_OVERFLING) { 2769 if (mFlingRunnable != null) { 2770 mFlingRunnable.endFling(); 2771 } 2772 if (mPositionScroller != null) { 2773 mPositionScroller.stop(); 2774 } 2775 2776 if (mScrollY != 0) { 2777 mScrollY = 0; 2778 invalidateParentCaches(); 2779 finishGlows(); 2780 invalidate(); 2781 } 2782 } 2783 } 2784 } 2785 2786 @Override 2787 public boolean onTouchEvent(MotionEvent ev) { 2788 if (!isEnabled()) { 2789 // A disabled view that is clickable still consumes the touch 2790 // events, it just doesn't respond to them. 2791 return isClickable() || isLongClickable(); 2792 } 2793 2794 if (mFastScroller != null) { 2795 boolean intercepted = mFastScroller.onTouchEvent(ev); 2796 if (intercepted) { 2797 return true; 2798 } 2799 } 2800 2801 final int action = ev.getAction(); 2802 2803 View v; 2804 int deltaY; 2805 2806 if (mVelocityTracker == null) { 2807 mVelocityTracker = VelocityTracker.obtain(); 2808 } 2809 mVelocityTracker.addMovement(ev); 2810 2811 switch (action & MotionEvent.ACTION_MASK) { 2812 case MotionEvent.ACTION_DOWN: { 2813 switch (mTouchMode) { 2814 case TOUCH_MODE_OVERFLING: { 2815 mFlingRunnable.endFling(); 2816 if (mPositionScroller != null) { 2817 mPositionScroller.stop(); 2818 } 2819 mTouchMode = TOUCH_MODE_OVERSCROLL; 2820 mMotionX = (int) ev.getX(); 2821 mMotionY = mLastY = (int) ev.getY(); 2822 mMotionCorrection = 0; 2823 mActivePointerId = ev.getPointerId(0); 2824 mDirection = 0; 2825 break; 2826 } 2827 2828 default: { 2829 mActivePointerId = ev.getPointerId(0); 2830 final int x = (int) ev.getX(); 2831 final int y = (int) ev.getY(); 2832 int motionPosition = pointToPosition(x, y); 2833 if (!mDataChanged) { 2834 if ((mTouchMode != TOUCH_MODE_FLING) && (motionPosition >= 0) 2835 && (getAdapter().isEnabled(motionPosition))) { 2836 // User clicked on an actual view (and was not stopping a fling). 2837 // It might be a click or a scroll. Assume it is a click until 2838 // proven otherwise 2839 mTouchMode = TOUCH_MODE_DOWN; 2840 // FIXME Debounce 2841 if (mPendingCheckForTap == null) { 2842 mPendingCheckForTap = new CheckForTap(); 2843 } 2844 postDelayed(mPendingCheckForTap, ViewConfiguration.getTapTimeout()); 2845 } else { 2846 if (mTouchMode == TOUCH_MODE_FLING) { 2847 // Stopped a fling. It is a scroll. 2848 createScrollingCache(); 2849 mTouchMode = TOUCH_MODE_SCROLL; 2850 mMotionCorrection = 0; 2851 motionPosition = findMotionRow(y); 2852 mFlingRunnable.flywheelTouch(); 2853 } 2854 } 2855 } 2856 2857 if (motionPosition >= 0) { 2858 // Remember where the motion event started 2859 v = getChildAt(motionPosition - mFirstPosition); 2860 mMotionViewOriginalTop = v.getTop(); 2861 } 2862 mMotionX = x; 2863 mMotionY = y; 2864 mMotionPosition = motionPosition; 2865 mLastY = Integer.MIN_VALUE; 2866 break; 2867 } 2868 } 2869 2870 if (performButtonActionOnTouchDown(ev)) { 2871 if (mTouchMode == TOUCH_MODE_DOWN) { 2872 removeCallbacks(mPendingCheckForTap); 2873 } 2874 } 2875 break; 2876 } 2877 2878 case MotionEvent.ACTION_MOVE: { 2879 int pointerIndex = ev.findPointerIndex(mActivePointerId); 2880 if (pointerIndex == -1) { 2881 pointerIndex = 0; 2882 mActivePointerId = ev.getPointerId(pointerIndex); 2883 } 2884 final int y = (int) ev.getY(pointerIndex); 2885 deltaY = y - mMotionY; 2886 switch (mTouchMode) { 2887 case TOUCH_MODE_DOWN: 2888 case TOUCH_MODE_TAP: 2889 case TOUCH_MODE_DONE_WAITING: 2890 // Check if we have moved far enough that it looks more like a 2891 // scroll than a tap 2892 startScrollIfNeeded(deltaY); 2893 break; 2894 case TOUCH_MODE_SCROLL: 2895 if (PROFILE_SCROLLING) { 2896 if (!mScrollProfilingStarted) { 2897 Debug.startMethodTracing("AbsListViewScroll"); 2898 mScrollProfilingStarted = true; 2899 } 2900 } 2901 2902 if (mScrollStrictSpan == null) { 2903 // If it's non-null, we're already in a scroll. 2904 mScrollStrictSpan = StrictMode.enterCriticalSpan("AbsListView-scroll"); 2905 } 2906 2907 if (y != mLastY) { 2908 // We may be here after stopping a fling and continuing to scroll. 2909 // If so, we haven't disallowed intercepting touch events yet. 2910 // Make sure that we do so in case we're in a parent that can intercept. 2911 if ((mGroupFlags & FLAG_DISALLOW_INTERCEPT) == 0 && 2912 Math.abs(deltaY) > mTouchSlop) { 2913 requestDisallowInterceptTouchEvent(true); 2914 } 2915 2916 final int rawDeltaY = deltaY; 2917 deltaY -= mMotionCorrection; 2918 int incrementalDeltaY = mLastY != Integer.MIN_VALUE ? y - mLastY : deltaY; 2919 2920 final int motionIndex; 2921 if (mMotionPosition >= 0) { 2922 motionIndex = mMotionPosition - mFirstPosition; 2923 } else { 2924 // If we don't have a motion position that we can reliably track, 2925 // pick something in the middle to make a best guess at things below. 2926 motionIndex = getChildCount() / 2; 2927 } 2928 2929 int motionViewPrevTop = 0; 2930 View motionView = this.getChildAt(motionIndex); 2931 if (motionView != null) { 2932 motionViewPrevTop = motionView.getTop(); 2933 } 2934 2935 // No need to do all this work if we're not going to move anyway 2936 boolean atEdge = false; 2937 if (incrementalDeltaY != 0) { 2938 atEdge = trackMotionScroll(deltaY, incrementalDeltaY); 2939 } 2940 2941 // Check to see if we have bumped into the scroll limit 2942 motionView = this.getChildAt(motionIndex); 2943 if (motionView != null) { 2944 // Check if the top of the motion view is where it is 2945 // supposed to be 2946 final int motionViewRealTop = motionView.getTop(); 2947 if (atEdge) { 2948 // Apply overscroll 2949 2950 int overscroll = -incrementalDeltaY - 2951 (motionViewRealTop - motionViewPrevTop); 2952 overScrollBy(0, overscroll, 0, mScrollY, 0, 0, 2953 0, mOverscrollDistance, true); 2954 if (Math.abs(mOverscrollDistance) == Math.abs(mScrollY)) { 2955 // Don't allow overfling if we're at the edge. 2956 mVelocityTracker.clear(); 2957 } 2958 2959 final int overscrollMode = getOverScrollMode(); 2960 if (overscrollMode == OVER_SCROLL_ALWAYS || 2961 (overscrollMode == OVER_SCROLL_IF_CONTENT_SCROLLS && 2962 !contentFits())) { 2963 mDirection = 0; // Reset when entering overscroll. 2964 mTouchMode = TOUCH_MODE_OVERSCROLL; 2965 if (rawDeltaY > 0) { 2966 mEdgeGlowTop.onPull((float) overscroll / getHeight()); 2967 if (!mEdgeGlowBottom.isFinished()) { 2968 mEdgeGlowBottom.onRelease(); 2969 } 2970 } else if (rawDeltaY < 0) { 2971 mEdgeGlowBottom.onPull((float) overscroll / getHeight()); 2972 if (!mEdgeGlowTop.isFinished()) { 2973 mEdgeGlowTop.onRelease(); 2974 } 2975 } 2976 } 2977 } 2978 mMotionY = y; 2979 invalidate(); 2980 } 2981 mLastY = y; 2982 } 2983 break; 2984 2985 case TOUCH_MODE_OVERSCROLL: 2986 if (y != mLastY) { 2987 final int rawDeltaY = deltaY; 2988 deltaY -= mMotionCorrection; 2989 int incrementalDeltaY = mLastY != Integer.MIN_VALUE ? y - mLastY : deltaY; 2990 2991 final int oldScroll = mScrollY; 2992 final int newScroll = oldScroll - incrementalDeltaY; 2993 int newDirection = y > mLastY ? 1 : -1; 2994 2995 if (mDirection == 0) { 2996 mDirection = newDirection; 2997 } 2998 2999 int overScrollDistance = -incrementalDeltaY; 3000 if ((newScroll < 0 && oldScroll >= 0) || (newScroll > 0 && oldScroll <= 0)) { 3001 overScrollDistance = -oldScroll; 3002 incrementalDeltaY += overScrollDistance; 3003 } else { 3004 incrementalDeltaY = 0; 3005 } 3006 3007 if (overScrollDistance != 0) { 3008 overScrollBy(0, overScrollDistance, 0, mScrollY, 0, 0, 3009 0, mOverscrollDistance, true); 3010 final int overscrollMode = getOverScrollMode(); 3011 if (overscrollMode == OVER_SCROLL_ALWAYS || 3012 (overscrollMode == OVER_SCROLL_IF_CONTENT_SCROLLS && 3013 !contentFits())) { 3014 if (rawDeltaY > 0) { 3015 mEdgeGlowTop.onPull((float) overScrollDistance / getHeight()); 3016 if (!mEdgeGlowBottom.isFinished()) { 3017 mEdgeGlowBottom.onRelease(); 3018 } 3019 } else if (rawDeltaY < 0) { 3020 mEdgeGlowBottom.onPull((float) overScrollDistance / getHeight()); 3021 if (!mEdgeGlowTop.isFinished()) { 3022 mEdgeGlowTop.onRelease(); 3023 } 3024 } 3025 invalidate(); 3026 } 3027 } 3028 3029 if (incrementalDeltaY != 0) { 3030 // Coming back to 'real' list scrolling 3031 mScrollY = 0; 3032 invalidateParentIfNeeded(); 3033 3034 // No need to do all this work if we're not going to move anyway 3035 if (incrementalDeltaY != 0) { 3036 trackMotionScroll(incrementalDeltaY, incrementalDeltaY); 3037 } 3038 3039 mTouchMode = TOUCH_MODE_SCROLL; 3040 3041 // We did not scroll the full amount. Treat this essentially like the 3042 // start of a new touch scroll 3043 final int motionPosition = findClosestMotionRow(y); 3044 3045 mMotionCorrection = 0; 3046 View motionView = getChildAt(motionPosition - mFirstPosition); 3047 mMotionViewOriginalTop = motionView != null ? motionView.getTop() : 0; 3048 mMotionY = y; 3049 mMotionPosition = motionPosition; 3050 } 3051 mLastY = y; 3052 mDirection = newDirection; 3053 } 3054 break; 3055 } 3056 3057 break; 3058 } 3059 3060 case MotionEvent.ACTION_UP: { 3061 switch (mTouchMode) { 3062 case TOUCH_MODE_DOWN: 3063 case TOUCH_MODE_TAP: 3064 case TOUCH_MODE_DONE_WAITING: 3065 final int motionPosition = mMotionPosition; 3066 final View child = getChildAt(motionPosition - mFirstPosition); 3067 3068 final float x = ev.getX(); 3069 final boolean inList = x > mListPadding.left && x < getWidth() - mListPadding.right; 3070 3071 if (child != null && !child.hasFocusable() && inList) { 3072 if (mTouchMode != TOUCH_MODE_DOWN) { 3073 child.setPressed(false); 3074 } 3075 3076 if (mPerformClick == null) { 3077 mPerformClick = new PerformClick(); 3078 } 3079 3080 final AbsListView.PerformClick performClick = mPerformClick; 3081 performClick.mClickMotionPosition = motionPosition; 3082 performClick.rememberWindowAttachCount(); 3083 3084 mResurrectToPosition = motionPosition; 3085 3086 if (mTouchMode == TOUCH_MODE_DOWN || mTouchMode == TOUCH_MODE_TAP) { 3087 final Handler handler = getHandler(); 3088 if (handler != null) { 3089 handler.removeCallbacks(mTouchMode == TOUCH_MODE_DOWN ? 3090 mPendingCheckForTap : mPendingCheckForLongPress); 3091 } 3092 mLayoutMode = LAYOUT_NORMAL; 3093 if (!mDataChanged && mAdapter.isEnabled(motionPosition)) { 3094 mTouchMode = TOUCH_MODE_TAP; 3095 setSelectedPositionInt(mMotionPosition); 3096 layoutChildren(); 3097 child.setPressed(true); 3098 positionSelector(mMotionPosition, child); 3099 setPressed(true); 3100 if (mSelector != null) { 3101 Drawable d = mSelector.getCurrent(); 3102 if (d != null && d instanceof TransitionDrawable) { 3103 ((TransitionDrawable) d).resetTransition(); 3104 } 3105 } 3106 if (mTouchModeReset != null) { 3107 removeCallbacks(mTouchModeReset); 3108 } 3109 mTouchModeReset = new Runnable() { 3110 @Override 3111 public void run() { 3112 mTouchMode = TOUCH_MODE_REST; 3113 child.setPressed(false); 3114 setPressed(false); 3115 if (!mDataChanged) { 3116 performClick.run(); 3117 } 3118 } 3119 }; 3120 postDelayed(mTouchModeReset, 3121 ViewConfiguration.getPressedStateDuration()); 3122 } else { 3123 mTouchMode = TOUCH_MODE_REST; 3124 updateSelectorState(); 3125 } 3126 return true; 3127 } else if (!mDataChanged && mAdapter.isEnabled(motionPosition)) { 3128 performClick.run(); 3129 } 3130 } 3131 mTouchMode = TOUCH_MODE_REST; 3132 updateSelectorState(); 3133 break; 3134 case TOUCH_MODE_SCROLL: 3135 final int childCount = getChildCount(); 3136 if (childCount > 0) { 3137 final int firstChildTop = getChildAt(0).getTop(); 3138 final int lastChildBottom = getChildAt(childCount - 1).getBottom(); 3139 final int contentTop = mListPadding.top; 3140 final int contentBottom = getHeight() - mListPadding.bottom; 3141 if (mFirstPosition == 0 && firstChildTop >= contentTop && 3142 mFirstPosition + childCount < mItemCount && 3143 lastChildBottom <= getHeight() - contentBottom) { 3144 mTouchMode = TOUCH_MODE_REST; 3145 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 3146 } else { 3147 final VelocityTracker velocityTracker = mVelocityTracker; 3148 velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity); 3149 3150 final int initialVelocity = (int) 3151 (velocityTracker.getYVelocity(mActivePointerId) * mVelocityScale); 3152 // Fling if we have enough velocity and we aren't at a boundary. 3153 // Since we can potentially overfling more than we can overscroll, don't 3154 // allow the weird behavior where you can scroll to a boundary then 3155 // fling further. 3156 if (Math.abs(initialVelocity) > mMinimumVelocity && 3157 !((mFirstPosition == 0 && 3158 firstChildTop == contentTop - mOverscrollDistance) || 3159 (mFirstPosition + childCount == mItemCount && 3160 lastChildBottom == contentBottom + mOverscrollDistance))) { 3161 if (mFlingRunnable == null) { 3162 mFlingRunnable = new FlingRunnable(); 3163 } 3164 reportScrollStateChange(OnScrollListener.SCROLL_STATE_FLING); 3165 3166 mFlingRunnable.start(-initialVelocity); 3167 } else { 3168 mTouchMode = TOUCH_MODE_REST; 3169 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 3170 if (mFlingRunnable != null) { 3171 mFlingRunnable.endFling(); 3172 } 3173 if (mPositionScroller != null) { 3174 mPositionScroller.stop(); 3175 } 3176 } 3177 } 3178 } else { 3179 mTouchMode = TOUCH_MODE_REST; 3180 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 3181 } 3182 break; 3183 3184 case TOUCH_MODE_OVERSCROLL: 3185 if (mFlingRunnable == null) { 3186 mFlingRunnable = new FlingRunnable(); 3187 } 3188 final VelocityTracker velocityTracker = mVelocityTracker; 3189 velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity); 3190 final int initialVelocity = (int) velocityTracker.getYVelocity(mActivePointerId); 3191 3192 reportScrollStateChange(OnScrollListener.SCROLL_STATE_FLING); 3193 if (Math.abs(initialVelocity) > mMinimumVelocity) { 3194 mFlingRunnable.startOverfling(-initialVelocity); 3195 } else { 3196 mFlingRunnable.startSpringback(); 3197 } 3198 3199 break; 3200 } 3201 3202 setPressed(false); 3203 3204 if (mEdgeGlowTop != null) { 3205 mEdgeGlowTop.onRelease(); 3206 mEdgeGlowBottom.onRelease(); 3207 } 3208 3209 // Need to redraw since we probably aren't drawing the selector anymore 3210 invalidate(); 3211 3212 final Handler handler = getHandler(); 3213 if (handler != null) { 3214 handler.removeCallbacks(mPendingCheckForLongPress); 3215 } 3216 3217 if (mVelocityTracker != null) { 3218 mVelocityTracker.recycle(); 3219 mVelocityTracker = null; 3220 } 3221 3222 mActivePointerId = INVALID_POINTER; 3223 3224 if (PROFILE_SCROLLING) { 3225 if (mScrollProfilingStarted) { 3226 Debug.stopMethodTracing(); 3227 mScrollProfilingStarted = false; 3228 } 3229 } 3230 3231 if (mScrollStrictSpan != null) { 3232 mScrollStrictSpan.finish(); 3233 mScrollStrictSpan = null; 3234 } 3235 break; 3236 } 3237 3238 case MotionEvent.ACTION_CANCEL: { 3239 switch (mTouchMode) { 3240 case TOUCH_MODE_OVERSCROLL: 3241 if (mFlingRunnable == null) { 3242 mFlingRunnable = new FlingRunnable(); 3243 } 3244 mFlingRunnable.startSpringback(); 3245 break; 3246 3247 case TOUCH_MODE_OVERFLING: 3248 // Do nothing - let it play out. 3249 break; 3250 3251 default: 3252 mTouchMode = TOUCH_MODE_REST; 3253 setPressed(false); 3254 View motionView = this.getChildAt(mMotionPosition - mFirstPosition); 3255 if (motionView != null) { 3256 motionView.setPressed(false); 3257 } 3258 clearScrollingCache(); 3259 3260 final Handler handler = getHandler(); 3261 if (handler != null) { 3262 handler.removeCallbacks(mPendingCheckForLongPress); 3263 } 3264 3265 if (mVelocityTracker != null) { 3266 mVelocityTracker.recycle(); 3267 mVelocityTracker = null; 3268 } 3269 } 3270 3271 if (mEdgeGlowTop != null) { 3272 mEdgeGlowTop.onRelease(); 3273 mEdgeGlowBottom.onRelease(); 3274 } 3275 mActivePointerId = INVALID_POINTER; 3276 break; 3277 } 3278 3279 case MotionEvent.ACTION_POINTER_UP: { 3280 onSecondaryPointerUp(ev); 3281 final int x = mMotionX; 3282 final int y = mMotionY; 3283 final int motionPosition = pointToPosition(x, y); 3284 if (motionPosition >= 0) { 3285 // Remember where the motion event started 3286 v = getChildAt(motionPosition - mFirstPosition); 3287 mMotionViewOriginalTop = v.getTop(); 3288 mMotionPosition = motionPosition; 3289 } 3290 mLastY = y; 3291 break; 3292 } 3293 3294 case MotionEvent.ACTION_POINTER_DOWN: { 3295 // New pointers take over dragging duties 3296 final int index = ev.getActionIndex(); 3297 final int id = ev.getPointerId(index); 3298 final int x = (int) ev.getX(index); 3299 final int y = (int) ev.getY(index); 3300 mMotionCorrection = 0; 3301 mActivePointerId = id; 3302 mMotionX = x; 3303 mMotionY = y; 3304 final int motionPosition = pointToPosition(x, y); 3305 if (motionPosition >= 0) { 3306 // Remember where the motion event started 3307 v = getChildAt(motionPosition - mFirstPosition); 3308 mMotionViewOriginalTop = v.getTop(); 3309 mMotionPosition = motionPosition; 3310 } 3311 mLastY = y; 3312 break; 3313 } 3314 } 3315 3316 return true; 3317 } 3318 3319 @Override 3320 protected void onOverScrolled(int scrollX, int scrollY, boolean clampedX, boolean clampedY) { 3321 if (mScrollY != scrollY) { 3322 onScrollChanged(mScrollX, scrollY, mScrollX, mScrollY); 3323 mScrollY = scrollY; 3324 invalidateParentIfNeeded(); 3325 3326 awakenScrollBars(); 3327 } 3328 } 3329 3330 @Override 3331 public boolean onGenericMotionEvent(MotionEvent event) { 3332 if ((event.getSource() & InputDevice.SOURCE_CLASS_POINTER) != 0) { 3333 switch (event.getAction()) { 3334 case MotionEvent.ACTION_SCROLL: { 3335 if (mTouchMode == TOUCH_MODE_REST) { 3336 final float vscroll = event.getAxisValue(MotionEvent.AXIS_VSCROLL); 3337 if (vscroll != 0) { 3338 final int delta = (int) (vscroll * getVerticalScrollFactor()); 3339 if (!trackMotionScroll(delta, delta)) { 3340 return true; 3341 } 3342 } 3343 } 3344 } 3345 } 3346 } 3347 return super.onGenericMotionEvent(event); 3348 } 3349 3350 @Override 3351 public void draw(Canvas canvas) { 3352 super.draw(canvas); 3353 if (mEdgeGlowTop != null) { 3354 final int scrollY = mScrollY; 3355 if (!mEdgeGlowTop.isFinished()) { 3356 final int restoreCount = canvas.save(); 3357 final int leftPadding = mListPadding.left + mGlowPaddingLeft; 3358 final int rightPadding = mListPadding.right + mGlowPaddingRight; 3359 final int width = getWidth() - leftPadding - rightPadding; 3360 3361 canvas.translate(leftPadding, 3362 Math.min(0, scrollY + mFirstPositionDistanceGuess)); 3363 mEdgeGlowTop.setSize(width, getHeight()); 3364 if (mEdgeGlowTop.draw(canvas)) { 3365 invalidate(); 3366 } 3367 canvas.restoreToCount(restoreCount); 3368 } 3369 if (!mEdgeGlowBottom.isFinished()) { 3370 final int restoreCount = canvas.save(); 3371 final int leftPadding = mListPadding.left + mGlowPaddingLeft; 3372 final int rightPadding = mListPadding.right + mGlowPaddingRight; 3373 final int width = getWidth() - leftPadding - rightPadding; 3374 final int height = getHeight(); 3375 3376 canvas.translate(-width + leftPadding, 3377 Math.max(height, scrollY + mLastPositionDistanceGuess)); 3378 canvas.rotate(180, width, 0); 3379 mEdgeGlowBottom.setSize(width, height); 3380 if (mEdgeGlowBottom.draw(canvas)) { 3381 invalidate(); 3382 } 3383 canvas.restoreToCount(restoreCount); 3384 } 3385 } 3386 if (mFastScroller != null) { 3387 final int scrollY = mScrollY; 3388 if (scrollY != 0) { 3389 // Pin to the top/bottom during overscroll 3390 int restoreCount = canvas.save(); 3391 canvas.translate(0, (float) scrollY); 3392 mFastScroller.draw(canvas); 3393 canvas.restoreToCount(restoreCount); 3394 } else { 3395 mFastScroller.draw(canvas); 3396 } 3397 } 3398 } 3399 3400 /** 3401 * @hide 3402 */ 3403 public void setOverScrollEffectPadding(int leftPadding, int rightPadding) { 3404 mGlowPaddingLeft = leftPadding; 3405 mGlowPaddingRight = rightPadding; 3406 } 3407 3408 @Override 3409 public boolean onInterceptTouchEvent(MotionEvent ev) { 3410 int action = ev.getAction(); 3411 View v; 3412 3413 if (mFastScroller != null) { 3414 boolean intercepted = mFastScroller.onInterceptTouchEvent(ev); 3415 if (intercepted) { 3416 return true; 3417 } 3418 } 3419 3420 switch (action & MotionEvent.ACTION_MASK) { 3421 case MotionEvent.ACTION_DOWN: { 3422 int touchMode = mTouchMode; 3423 if (touchMode == TOUCH_MODE_OVERFLING || touchMode == TOUCH_MODE_OVERSCROLL) { 3424 mMotionCorrection = 0; 3425 return true; 3426 } 3427 3428 final int x = (int) ev.getX(); 3429 final int y = (int) ev.getY(); 3430 mActivePointerId = ev.getPointerId(0); 3431 3432 int motionPosition = findMotionRow(y); 3433 if (touchMode != TOUCH_MODE_FLING && motionPosition >= 0) { 3434 // User clicked on an actual view (and was not stopping a fling). 3435 // Remember where the motion event started 3436 v = getChildAt(motionPosition - mFirstPosition); 3437 mMotionViewOriginalTop = v.getTop(); 3438 mMotionX = x; 3439 mMotionY = y; 3440 mMotionPosition = motionPosition; 3441 mTouchMode = TOUCH_MODE_DOWN; 3442 clearScrollingCache(); 3443 } 3444 mLastY = Integer.MIN_VALUE; 3445 if (touchMode == TOUCH_MODE_FLING) { 3446 return true; 3447 } 3448 break; 3449 } 3450 3451 case MotionEvent.ACTION_MOVE: { 3452 switch (mTouchMode) { 3453 case TOUCH_MODE_DOWN: 3454 int pointerIndex = ev.findPointerIndex(mActivePointerId); 3455 if (pointerIndex == -1) { 3456 pointerIndex = 0; 3457 mActivePointerId = ev.getPointerId(pointerIndex); 3458 } 3459 final int y = (int) ev.getY(pointerIndex); 3460 if (startScrollIfNeeded(y - mMotionY)) { 3461 return true; 3462 } 3463 break; 3464 } 3465 break; 3466 } 3467 3468 case MotionEvent.ACTION_UP: { 3469 mTouchMode = TOUCH_MODE_REST; 3470 mActivePointerId = INVALID_POINTER; 3471 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 3472 break; 3473 } 3474 3475 case MotionEvent.ACTION_POINTER_UP: { 3476 onSecondaryPointerUp(ev); 3477 break; 3478 } 3479 } 3480 3481 return false; 3482 } 3483 3484 private void onSecondaryPointerUp(MotionEvent ev) { 3485 final int pointerIndex = (ev.getAction() & MotionEvent.ACTION_POINTER_INDEX_MASK) >> 3486 MotionEvent.ACTION_POINTER_INDEX_SHIFT; 3487 final int pointerId = ev.getPointerId(pointerIndex); 3488 if (pointerId == mActivePointerId) { 3489 // This was our active pointer going up. Choose a new 3490 // active pointer and adjust accordingly. 3491 // TODO: Make this decision more intelligent. 3492 final int newPointerIndex = pointerIndex == 0 ? 1 : 0; 3493 mMotionX = (int) ev.getX(newPointerIndex); 3494 mMotionY = (int) ev.getY(newPointerIndex); 3495 mMotionCorrection = 0; 3496 mActivePointerId = ev.getPointerId(newPointerIndex); 3497 } 3498 } 3499 3500 /** 3501 * {@inheritDoc} 3502 */ 3503 @Override 3504 public void addTouchables(ArrayList<View> views) { 3505 final int count = getChildCount(); 3506 final int firstPosition = mFirstPosition; 3507 final ListAdapter adapter = mAdapter; 3508 3509 if (adapter == null) { 3510 return; 3511 } 3512 3513 for (int i = 0; i < count; i++) { 3514 final View child = getChildAt(i); 3515 if (adapter.isEnabled(firstPosition + i)) { 3516 views.add(child); 3517 } 3518 child.addTouchables(views); 3519 } 3520 } 3521 3522 /** 3523 * Fires an "on scroll state changed" event to the registered 3524 * {@link android.widget.AbsListView.OnScrollListener}, if any. The state change 3525 * is fired only if the specified state is different from the previously known state. 3526 * 3527 * @param newState The new scroll state. 3528 */ 3529 void reportScrollStateChange(int newState) { 3530 if (newState != mLastScrollState) { 3531 if (mOnScrollListener != null) { 3532 mLastScrollState = newState; 3533 mOnScrollListener.onScrollStateChanged(this, newState); 3534 } 3535 } 3536 } 3537 3538 /** 3539 * Responsible for fling behavior. Use {@link #start(int)} to 3540 * initiate a fling. Each frame of the fling is handled in {@link #run()}. 3541 * A FlingRunnable will keep re-posting itself until the fling is done. 3542 * 3543 */ 3544 private class FlingRunnable implements Runnable { 3545 /** 3546 * Tracks the decay of a fling scroll 3547 */ 3548 private final OverScroller mScroller; 3549 3550 /** 3551 * Y value reported by mScroller on the previous fling 3552 */ 3553 private int mLastFlingY; 3554 3555 private final Runnable mCheckFlywheel = new Runnable() { 3556 public void run() { 3557 final int activeId = mActivePointerId; 3558 final VelocityTracker vt = mVelocityTracker; 3559 final OverScroller scroller = mScroller; 3560 if (vt == null || activeId == INVALID_POINTER) { 3561 return; 3562 } 3563 3564 vt.computeCurrentVelocity(1000, mMaximumVelocity); 3565 final float yvel = -vt.getYVelocity(activeId); 3566 3567 if (scroller.isScrollingInDirection(0, yvel)) { 3568 // Keep the fling alive a little longer 3569 postDelayed(this, FLYWHEEL_TIMEOUT); 3570 } else { 3571 endFling(); 3572 mTouchMode = TOUCH_MODE_SCROLL; 3573 reportScrollStateChange(OnScrollListener.SCROLL_STATE_TOUCH_SCROLL); 3574 } 3575 } 3576 }; 3577 3578 private static final int FLYWHEEL_TIMEOUT = 40; // milliseconds 3579 3580 FlingRunnable() { 3581 mScroller = new OverScroller(getContext()); 3582 } 3583 3584 void start(int initialVelocity) { 3585 int initialY = initialVelocity < 0 ? Integer.MAX_VALUE : 0; 3586 mLastFlingY = initialY; 3587 mScroller.fling(0, initialY, 0, initialVelocity, 3588 0, Integer.MAX_VALUE, 0, Integer.MAX_VALUE); 3589 mTouchMode = TOUCH_MODE_FLING; 3590 post(this); 3591 3592 if (PROFILE_FLINGING) { 3593 if (!mFlingProfilingStarted) { 3594 Debug.startMethodTracing("AbsListViewFling"); 3595 mFlingProfilingStarted = true; 3596 } 3597 } 3598 3599 if (mFlingStrictSpan == null) { 3600 mFlingStrictSpan = StrictMode.enterCriticalSpan("AbsListView-fling"); 3601 } 3602 } 3603 3604 void startSpringback() { 3605 if (mScroller.springBack(0, mScrollY, 0, 0, 0, 0)) { 3606 mTouchMode = TOUCH_MODE_OVERFLING; 3607 invalidate(); 3608 post(this); 3609 } else { 3610 mTouchMode = TOUCH_MODE_REST; 3611 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 3612 } 3613 } 3614 3615 void startOverfling(int initialVelocity) { 3616 mScroller.fling(0, mScrollY, 0, initialVelocity, 0, 0, 3617 Integer.MIN_VALUE, Integer.MAX_VALUE, 0, getHeight()); 3618 mTouchMode = TOUCH_MODE_OVERFLING; 3619 invalidate(); 3620 post(this); 3621 } 3622 3623 void edgeReached(int delta) { 3624 mScroller.notifyVerticalEdgeReached(mScrollY, 0, mOverflingDistance); 3625 final int overscrollMode = getOverScrollMode(); 3626 if (overscrollMode == OVER_SCROLL_ALWAYS || 3627 (overscrollMode == OVER_SCROLL_IF_CONTENT_SCROLLS && !contentFits())) { 3628 mTouchMode = TOUCH_MODE_OVERFLING; 3629 final int vel = (int) mScroller.getCurrVelocity(); 3630 if (delta > 0) { 3631 mEdgeGlowTop.onAbsorb(vel); 3632 } else { 3633 mEdgeGlowBottom.onAbsorb(vel); 3634 } 3635 } else { 3636 mTouchMode = TOUCH_MODE_REST; 3637 if (mPositionScroller != null) { 3638 mPositionScroller.stop(); 3639 } 3640 } 3641 invalidate(); 3642 post(this); 3643 } 3644 3645 void startScroll(int distance, int duration) { 3646 int initialY = distance < 0 ? Integer.MAX_VALUE : 0; 3647 mLastFlingY = initialY; 3648 mScroller.startScroll(0, initialY, 0, distance, duration); 3649 mTouchMode = TOUCH_MODE_FLING; 3650 post(this); 3651 } 3652 3653 void endFling() { 3654 mTouchMode = TOUCH_MODE_REST; 3655 3656 removeCallbacks(this); 3657 removeCallbacks(mCheckFlywheel); 3658 3659 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 3660 clearScrollingCache(); 3661 mScroller.abortAnimation(); 3662 3663 if (mFlingStrictSpan != null) { 3664 mFlingStrictSpan.finish(); 3665 mFlingStrictSpan = null; 3666 } 3667 } 3668 3669 void flywheelTouch() { 3670 postDelayed(mCheckFlywheel, FLYWHEEL_TIMEOUT); 3671 } 3672 3673 public void run() { 3674 switch (mTouchMode) { 3675 default: 3676 endFling(); 3677 return; 3678 3679 case TOUCH_MODE_SCROLL: 3680 if (mScroller.isFinished()) { 3681 return; 3682 } 3683 // Fall through 3684 case TOUCH_MODE_FLING: { 3685 if (mItemCount == 0 || getChildCount() == 0) { 3686 endFling(); 3687 return; 3688 } 3689 3690 final OverScroller scroller = mScroller; 3691 boolean more = scroller.computeScrollOffset(); 3692 final int y = scroller.getCurrY(); 3693 3694 // Flip sign to convert finger direction to list items direction 3695 // (e.g. finger moving down means list is moving towards the top) 3696 int delta = mLastFlingY - y; 3697 3698 // Pretend that each frame of a fling scroll is a touch scroll 3699 if (delta > 0) { 3700 // List is moving towards the top. Use first view as mMotionPosition 3701 mMotionPosition = mFirstPosition; 3702 final View firstView = getChildAt(0); 3703 mMotionViewOriginalTop = firstView.getTop(); 3704 3705 // Don't fling more than 1 screen 3706 delta = Math.min(getHeight() - mPaddingBottom - mPaddingTop - 1, delta); 3707 } else { 3708 // List is moving towards the bottom. Use last view as mMotionPosition 3709 int offsetToLast = getChildCount() - 1; 3710 mMotionPosition = mFirstPosition + offsetToLast; 3711 3712 final View lastView = getChildAt(offsetToLast); 3713 mMotionViewOriginalTop = lastView.getTop(); 3714 3715 // Don't fling more than 1 screen 3716 delta = Math.max(-(getHeight() - mPaddingBottom - mPaddingTop - 1), delta); 3717 } 3718 3719 // Check to see if we have bumped into the scroll limit 3720 View motionView = getChildAt(mMotionPosition - mFirstPosition); 3721 int oldTop = 0; 3722 if (motionView != null) { 3723 oldTop = motionView.getTop(); 3724 } 3725 3726 // Don't stop just because delta is zero (it could have been rounded) 3727 final boolean atEnd = trackMotionScroll(delta, delta) && (delta != 0); 3728 if (atEnd) { 3729 if (motionView != null) { 3730 // Tweak the scroll for how far we overshot 3731 int overshoot = -(delta - (motionView.getTop() - oldTop)); 3732 overScrollBy(0, overshoot, 0, mScrollY, 0, 0, 3733 0, mOverflingDistance, false); 3734 } 3735 if (more) { 3736 edgeReached(delta); 3737 } 3738 break; 3739 } 3740 3741 if (more && !atEnd) { 3742 invalidate(); 3743 mLastFlingY = y; 3744 post(this); 3745 } else { 3746 endFling(); 3747 3748 if (PROFILE_FLINGING) { 3749 if (mFlingProfilingStarted) { 3750 Debug.stopMethodTracing(); 3751 mFlingProfilingStarted = false; 3752 } 3753 3754 if (mFlingStrictSpan != null) { 3755 mFlingStrictSpan.finish(); 3756 mFlingStrictSpan = null; 3757 } 3758 } 3759 } 3760 break; 3761 } 3762 3763 case TOUCH_MODE_OVERFLING: { 3764 final OverScroller scroller = mScroller; 3765 if (scroller.computeScrollOffset()) { 3766 final int scrollY = mScrollY; 3767 final int currY = scroller.getCurrY(); 3768 final int deltaY = currY - scrollY; 3769 if (overScrollBy(0, deltaY, 0, scrollY, 0, 0, 3770 0, mOverflingDistance, false)) { 3771 final boolean crossDown = scrollY <= 0 && currY > 0; 3772 final boolean crossUp = scrollY >= 0 && currY < 0; 3773 if (crossDown || crossUp) { 3774 int velocity = (int) scroller.getCurrVelocity(); 3775 if (crossUp) velocity = -velocity; 3776 3777 // Don't flywheel from this; we're just continuing things. 3778 scroller.abortAnimation(); 3779 start(velocity); 3780 } else { 3781 startSpringback(); 3782 } 3783 } else { 3784 invalidate(); 3785 post(this); 3786 } 3787 } else { 3788 endFling(); 3789 } 3790 break; 3791 } 3792 } 3793 } 3794 } 3795 3796 3797 class PositionScroller implements Runnable { 3798 private static final int SCROLL_DURATION = 400; 3799 3800 private static final int MOVE_DOWN_POS = 1; 3801 private static final int MOVE_UP_POS = 2; 3802 private static final int MOVE_DOWN_BOUND = 3; 3803 private static final int MOVE_UP_BOUND = 4; 3804 private static final int MOVE_OFFSET = 5; 3805 3806 private int mMode; 3807 private int mTargetPos; 3808 private int mBoundPos; 3809 private int mLastSeenPos; 3810 private int mScrollDuration; 3811 private final int mExtraScroll; 3812 3813 private int mOffsetFromTop; 3814 3815 PositionScroller() { 3816 mExtraScroll = ViewConfiguration.get(mContext).getScaledFadingEdgeLength(); 3817 } 3818 3819 void start(int position) { 3820 stop(); 3821 3822 final int firstPos = mFirstPosition; 3823 final int lastPos = firstPos + getChildCount() - 1; 3824 3825 int viewTravelCount; 3826 if (position <= firstPos) { 3827 viewTravelCount = firstPos - position + 1; 3828 mMode = MOVE_UP_POS; 3829 } else if (position >= lastPos) { 3830 viewTravelCount = position - lastPos + 1; 3831 mMode = MOVE_DOWN_POS; 3832 } else { 3833 // Already on screen, nothing to do 3834 return; 3835 } 3836 3837 if (viewTravelCount > 0) { 3838 mScrollDuration = SCROLL_DURATION / viewTravelCount; 3839 } else { 3840 mScrollDuration = SCROLL_DURATION; 3841 } 3842 mTargetPos = position; 3843 mBoundPos = INVALID_POSITION; 3844 mLastSeenPos = INVALID_POSITION; 3845 3846 post(this); 3847 } 3848 3849 void start(int position, int boundPosition) { 3850 stop(); 3851 3852 if (boundPosition == INVALID_POSITION) { 3853 start(position); 3854 return; 3855 } 3856 3857 final int firstPos = mFirstPosition; 3858 final int lastPos = firstPos + getChildCount() - 1; 3859 3860 int viewTravelCount; 3861 if (position <= firstPos) { 3862 final int boundPosFromLast = lastPos - boundPosition; 3863 if (boundPosFromLast < 1) { 3864 // Moving would shift our bound position off the screen. Abort. 3865 return; 3866 } 3867 3868 final int posTravel = firstPos - position + 1; 3869 final int boundTravel = boundPosFromLast - 1; 3870 if (boundTravel < posTravel) { 3871 viewTravelCount = boundTravel; 3872 mMode = MOVE_UP_BOUND; 3873 } else { 3874 viewTravelCount = posTravel; 3875 mMode = MOVE_UP_POS; 3876 } 3877 } else if (position >= lastPos) { 3878 final int boundPosFromFirst = boundPosition - firstPos; 3879 if (boundPosFromFirst < 1) { 3880 // Moving would shift our bound position off the screen. Abort. 3881 return; 3882 } 3883 3884 final int posTravel = position - lastPos + 1; 3885 final int boundTravel = boundPosFromFirst - 1; 3886 if (boundTravel < posTravel) { 3887 viewTravelCount = boundTravel; 3888 mMode = MOVE_DOWN_BOUND; 3889 } else { 3890 viewTravelCount = posTravel; 3891 mMode = MOVE_DOWN_POS; 3892 } 3893 } else { 3894 // Already on screen, nothing to do 3895 return; 3896 } 3897 3898 if (viewTravelCount > 0) { 3899 mScrollDuration = SCROLL_DURATION / viewTravelCount; 3900 } else { 3901 mScrollDuration = SCROLL_DURATION; 3902 } 3903 mTargetPos = position; 3904 mBoundPos = boundPosition; 3905 mLastSeenPos = INVALID_POSITION; 3906 3907 post(this); 3908 } 3909 3910 void startWithOffset(int position, int offset) { 3911 startWithOffset(position, offset, SCROLL_DURATION); 3912 } 3913 3914 void startWithOffset(int position, int offset, int duration) { 3915 stop(); 3916 3917 mTargetPos = position; 3918 mOffsetFromTop = offset; 3919 mBoundPos = INVALID_POSITION; 3920 mLastSeenPos = INVALID_POSITION; 3921 mMode = MOVE_OFFSET; 3922 3923 final int firstPos = mFirstPosition; 3924 final int childCount = getChildCount(); 3925 final int lastPos = firstPos + childCount - 1; 3926 3927 int viewTravelCount; 3928 if (position < firstPos) { 3929 viewTravelCount = firstPos - position; 3930 } else if (position > lastPos) { 3931 viewTravelCount = position - lastPos; 3932 } else { 3933 // On-screen, just scroll. 3934 final int targetTop = getChildAt(position - firstPos).getTop(); 3935 smoothScrollBy(targetTop - offset, duration); 3936 return; 3937 } 3938 3939 // Estimate how many screens we should travel 3940 final float screenTravelCount = (float) viewTravelCount / childCount; 3941 mScrollDuration = screenTravelCount < 1 ? (int) (screenTravelCount * duration) : 3942 (int) (duration / screenTravelCount); 3943 mLastSeenPos = INVALID_POSITION; 3944 3945 post(this); 3946 } 3947 3948 void stop() { 3949 removeCallbacks(this); 3950 } 3951 3952 public void run() { 3953 if (mTouchMode != TOUCH_MODE_FLING && mLastSeenPos != INVALID_POSITION) { 3954 return; 3955 } 3956 3957 final int listHeight = getHeight(); 3958 final int firstPos = mFirstPosition; 3959 3960 switch (mMode) { 3961 case MOVE_DOWN_POS: { 3962 final int lastViewIndex = getChildCount() - 1; 3963 final int lastPos = firstPos + lastViewIndex; 3964 3965 if (lastViewIndex < 0) { 3966 return; 3967 } 3968 3969 if (lastPos == mLastSeenPos) { 3970 // No new views, let things keep going. 3971 post(this); 3972 return; 3973 } 3974 3975 final View lastView = getChildAt(lastViewIndex); 3976 final int lastViewHeight = lastView.getHeight(); 3977 final int lastViewTop = lastView.getTop(); 3978 final int lastViewPixelsShowing = listHeight - lastViewTop; 3979 final int extraScroll = lastPos < mItemCount - 1 ? mExtraScroll : mListPadding.bottom; 3980 3981 smoothScrollBy(lastViewHeight - lastViewPixelsShowing + extraScroll, 3982 mScrollDuration); 3983 3984 mLastSeenPos = lastPos; 3985 if (lastPos < mTargetPos) { 3986 post(this); 3987 } 3988 break; 3989 } 3990 3991 case MOVE_DOWN_BOUND: { 3992 final int nextViewIndex = 1; 3993 final int childCount = getChildCount(); 3994 3995 if (firstPos == mBoundPos || childCount <= nextViewIndex 3996 || firstPos + childCount >= mItemCount) { 3997 return; 3998 } 3999 final int nextPos = firstPos + nextViewIndex; 4000 4001 if (nextPos == mLastSeenPos) { 4002 // No new views, let things keep going. 4003 post(this); 4004 return; 4005 } 4006 4007 final View nextView = getChildAt(nextViewIndex); 4008 final int nextViewHeight = nextView.getHeight(); 4009 final int nextViewTop = nextView.getTop(); 4010 final int extraScroll = mExtraScroll; 4011 if (nextPos < mBoundPos) { 4012 smoothScrollBy(Math.max(0, nextViewHeight + nextViewTop - extraScroll), 4013 mScrollDuration); 4014 4015 mLastSeenPos = nextPos; 4016 4017 post(this); 4018 } else { 4019 if (nextViewTop > extraScroll) { 4020 smoothScrollBy(nextViewTop - extraScroll, mScrollDuration); 4021 } 4022 } 4023 break; 4024 } 4025 4026 case MOVE_UP_POS: { 4027 if (firstPos == mLastSeenPos) { 4028 // No new views, let things keep going. 4029 post(this); 4030 return; 4031 } 4032 4033 final View firstView = getChildAt(0); 4034 if (firstView == null) { 4035 return; 4036 } 4037 final int firstViewTop = firstView.getTop(); 4038 final int extraScroll = firstPos > 0 ? mExtraScroll : mListPadding.top; 4039 4040 smoothScrollBy(firstViewTop - extraScroll, mScrollDuration); 4041 4042 mLastSeenPos = firstPos; 4043 4044 if (firstPos > mTargetPos) { 4045 post(this); 4046 } 4047 break; 4048 } 4049 4050 case MOVE_UP_BOUND: { 4051 final int lastViewIndex = getChildCount() - 2; 4052 if (lastViewIndex < 0) { 4053 return; 4054 } 4055 final int lastPos = firstPos + lastViewIndex; 4056 4057 if (lastPos == mLastSeenPos) { 4058 // No new views, let things keep going. 4059 post(this); 4060 return; 4061 } 4062 4063 final View lastView = getChildAt(lastViewIndex); 4064 final int lastViewHeight = lastView.getHeight(); 4065 final int lastViewTop = lastView.getTop(); 4066 final int lastViewPixelsShowing = listHeight - lastViewTop; 4067 mLastSeenPos = lastPos; 4068 if (lastPos > mBoundPos) { 4069 smoothScrollBy(-(lastViewPixelsShowing - mExtraScroll), mScrollDuration); 4070 post(this); 4071 } else { 4072 final int bottom = listHeight - mExtraScroll; 4073 final int lastViewBottom = lastViewTop + lastViewHeight; 4074 if (bottom > lastViewBottom) { 4075 smoothScrollBy(-(bottom - lastViewBottom), mScrollDuration); 4076 } 4077 } 4078 break; 4079 } 4080 4081 case MOVE_OFFSET: { 4082 if (mLastSeenPos == firstPos) { 4083 // No new views, let things keep going. 4084 post(this); 4085 return; 4086 } 4087 4088 mLastSeenPos = firstPos; 4089 4090 final int childCount = getChildCount(); 4091 final int position = mTargetPos; 4092 final int lastPos = firstPos + childCount - 1; 4093 4094 int viewTravelCount = 0; 4095 if (position < firstPos) { 4096 viewTravelCount = firstPos - position + 1; 4097 } else if (position > lastPos) { 4098 viewTravelCount = position - lastPos; 4099 } 4100 4101 // Estimate how many screens we should travel 4102 final float screenTravelCount = (float) viewTravelCount / childCount; 4103 4104 final float modifier = Math.min(Math.abs(screenTravelCount), 1.f); 4105 if (position < firstPos) { 4106 smoothScrollBy((int) (-getHeight() * modifier), mScrollDuration); 4107 post(this); 4108 } else if (position > lastPos) { 4109 smoothScrollBy((int) (getHeight() * modifier), mScrollDuration); 4110 post(this); 4111 } else { 4112 // On-screen, just scroll. 4113 final int targetTop = getChildAt(position - firstPos).getTop(); 4114 final int distance = targetTop - mOffsetFromTop; 4115 smoothScrollBy(distance, 4116 (int) (mScrollDuration * ((float) distance / getHeight()))); 4117 } 4118 break; 4119 } 4120 4121 default: 4122 break; 4123 } 4124 } 4125 } 4126 4127 /** 4128 * The amount of friction applied to flings. The default value 4129 * is {@link ViewConfiguration#getScrollFriction}. 4130 * 4131 * @return A scalar dimensionless value representing the coefficient of 4132 * friction. 4133 */ 4134 public void setFriction(float friction) { 4135 if (mFlingRunnable == null) { 4136 mFlingRunnable = new FlingRunnable(); 4137 } 4138 mFlingRunnable.mScroller.setFriction(friction); 4139 } 4140 4141 /** 4142 * Sets a scale factor for the fling velocity. The initial scale 4143 * factor is 1.0. 4144 * 4145 * @param scale The scale factor to multiply the velocity by. 4146 */ 4147 public void setVelocityScale(float scale) { 4148 mVelocityScale = scale; 4149 } 4150 4151 /** 4152 * Smoothly scroll to the specified adapter position. The view will 4153 * scroll such that the indicated position is displayed. 4154 * @param position Scroll to this adapter position. 4155 */ 4156 public void smoothScrollToPosition(int position) { 4157 if (mPositionScroller == null) { 4158 mPositionScroller = new PositionScroller(); 4159 } 4160 mPositionScroller.start(position); 4161 } 4162 4163 /** 4164 * Smoothly scroll to the specified adapter position. The view will scroll 4165 * such that the indicated position is displayed <code>offset</code> pixels from 4166 * the top edge of the view. If this is impossible, (e.g. the offset would scroll 4167 * the first or last item beyond the boundaries of the list) it will get as close 4168 * as possible. The scroll will take <code>duration</code> milliseconds to complete. 4169 * 4170 * @param position Position to scroll to 4171 * @param offset Desired distance in pixels of <code>position</code> from the top 4172 * of the view when scrolling is finished 4173 * @param duration Number of milliseconds to use for the scroll 4174 */ 4175 public void smoothScrollToPositionFromTop(int position, int offset, int duration) { 4176 if (mPositionScroller == null) { 4177 mPositionScroller = new PositionScroller(); 4178 } 4179 mPositionScroller.startWithOffset(position, offset, duration); 4180 } 4181 4182 /** 4183 * Smoothly scroll to the specified adapter position. The view will scroll 4184 * such that the indicated position is displayed <code>offset</code> pixels from 4185 * the top edge of the view. If this is impossible, (e.g. the offset would scroll 4186 * the first or last item beyond the boundaries of the list) it will get as close 4187 * as possible. 4188 * 4189 * @param position Position to scroll to 4190 * @param offset Desired distance in pixels of <code>position</code> from the top 4191 * of the view when scrolling is finished 4192 */ 4193 public void smoothScrollToPositionFromTop(int position, int offset) { 4194 if (mPositionScroller == null) { 4195 mPositionScroller = new PositionScroller(); 4196 } 4197 mPositionScroller.startWithOffset(position, offset); 4198 } 4199 4200 /** 4201 * Smoothly scroll to the specified adapter position. The view will 4202 * scroll such that the indicated position is displayed, but it will 4203 * stop early if scrolling further would scroll boundPosition out of 4204 * view. 4205 * @param position Scroll to this adapter position. 4206 * @param boundPosition Do not scroll if it would move this adapter 4207 * position out of view. 4208 */ 4209 public void smoothScrollToPosition(int position, int boundPosition) { 4210 if (mPositionScroller == null) { 4211 mPositionScroller = new PositionScroller(); 4212 } 4213 mPositionScroller.start(position, boundPosition); 4214 } 4215 4216 /** 4217 * Smoothly scroll by distance pixels over duration milliseconds. 4218 * @param distance Distance to scroll in pixels. 4219 * @param duration Duration of the scroll animation in milliseconds. 4220 */ 4221 public void smoothScrollBy(int distance, int duration) { 4222 if (mFlingRunnable == null) { 4223 mFlingRunnable = new FlingRunnable(); 4224 } 4225 4226 // No sense starting to scroll if we're not going anywhere 4227 final int firstPos = mFirstPosition; 4228 final int childCount = getChildCount(); 4229 final int lastPos = firstPos + childCount; 4230 final int topLimit = getPaddingTop(); 4231 final int bottomLimit = getHeight() - getPaddingBottom(); 4232 4233 if (distance == 0 || mItemCount == 0 || childCount == 0 || 4234 (firstPos == 0 && getChildAt(0).getTop() == topLimit && distance < 0) || 4235 (lastPos == mItemCount - 1 && 4236 getChildAt(childCount - 1).getBottom() == bottomLimit && distance > 0)) { 4237 mFlingRunnable.endFling(); 4238 if (mPositionScroller != null) { 4239 mPositionScroller.stop(); 4240 } 4241 } else { 4242 reportScrollStateChange(OnScrollListener.SCROLL_STATE_FLING); 4243 mFlingRunnable.startScroll(distance, duration); 4244 } 4245 } 4246 4247 /** 4248 * Allows RemoteViews to scroll relatively to a position. 4249 */ 4250 void smoothScrollByOffset(int position) { 4251 int index = -1; 4252 if (position < 0) { 4253 index = getFirstVisiblePosition(); 4254 } else if (position > 0) { 4255 index = getLastVisiblePosition(); 4256 } 4257 4258 if (index > -1) { 4259 View child = getChildAt(index - getFirstVisiblePosition()); 4260 if (child != null) { 4261 Rect visibleRect = new Rect(); 4262 if (child.getGlobalVisibleRect(visibleRect)) { 4263 // the child is partially visible 4264 int childRectArea = child.getWidth() * child.getHeight(); 4265 int visibleRectArea = visibleRect.width() * visibleRect.height(); 4266 float visibleArea = (visibleRectArea / (float) childRectArea); 4267 final float visibleThreshold = 0.75f; 4268 if ((position < 0) && (visibleArea < visibleThreshold)) { 4269 // the top index is not perceivably visible so offset 4270 // to account for showing that top index as well 4271 ++index; 4272 } else if ((position > 0) && (visibleArea < visibleThreshold)) { 4273 // the bottom index is not perceivably visible so offset 4274 // to account for showing that bottom index as well 4275 --index; 4276 } 4277 } 4278 smoothScrollToPosition(Math.max(0, Math.min(getCount(), index + position))); 4279 } 4280 } 4281 } 4282 4283 private void createScrollingCache() { 4284 if (mScrollingCacheEnabled && !mCachingStarted) { 4285 setChildrenDrawnWithCacheEnabled(true); 4286 setChildrenDrawingCacheEnabled(true); 4287 mCachingStarted = mCachingActive = true; 4288 } 4289 } 4290 4291 private void clearScrollingCache() { 4292 if (mClearScrollingCache == null) { 4293 mClearScrollingCache = new Runnable() { 4294 public void run() { 4295 if (mCachingStarted) { 4296 mCachingStarted = mCachingActive = false; 4297 setChildrenDrawnWithCacheEnabled(false); 4298 if ((mPersistentDrawingCache & PERSISTENT_SCROLLING_CACHE) == 0) { 4299 setChildrenDrawingCacheEnabled(false); 4300 } 4301 if (!isAlwaysDrawnWithCacheEnabled()) { 4302 invalidate(); 4303 } 4304 } 4305 } 4306 }; 4307 } 4308 post(mClearScrollingCache); 4309 } 4310 4311 /** 4312 * Track a motion scroll 4313 * 4314 * @param deltaY Amount to offset mMotionView. This is the accumulated delta since the motion 4315 * began. Positive numbers mean the user's finger is moving down the screen. 4316 * @param incrementalDeltaY Change in deltaY from the previous event. 4317 * @return true if we're already at the beginning/end of the list and have nothing to do. 4318 */ 4319 boolean trackMotionScroll(int deltaY, int incrementalDeltaY) { 4320 final int childCount = getChildCount(); 4321 if (childCount == 0) { 4322 return true; 4323 } 4324 4325 final int firstTop = getChildAt(0).getTop(); 4326 final int lastBottom = getChildAt(childCount - 1).getBottom(); 4327 4328 final Rect listPadding = mListPadding; 4329 4330 // "effective padding" In this case is the amount of padding that affects 4331 // how much space should not be filled by items. If we don't clip to padding 4332 // there is no effective padding. 4333 int effectivePaddingTop = 0; 4334 int effectivePaddingBottom = 0; 4335 if ((mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK) { 4336 effectivePaddingTop = listPadding.top; 4337 effectivePaddingBottom = listPadding.bottom; 4338 } 4339 4340 // FIXME account for grid vertical spacing too? 4341 final int spaceAbove = effectivePaddingTop - firstTop; 4342 final int end = getHeight() - effectivePaddingBottom; 4343 final int spaceBelow = lastBottom - end; 4344 4345 final int height = getHeight() - mPaddingBottom - mPaddingTop; 4346 if (deltaY < 0) { 4347 deltaY = Math.max(-(height - 1), deltaY); 4348 } else { 4349 deltaY = Math.min(height - 1, deltaY); 4350 } 4351 4352 if (incrementalDeltaY < 0) { 4353 incrementalDeltaY = Math.max(-(height - 1), incrementalDeltaY); 4354 } else { 4355 incrementalDeltaY = Math.min(height - 1, incrementalDeltaY); 4356 } 4357 4358 final int firstPosition = mFirstPosition; 4359 4360 // Update our guesses for where the first and last views are 4361 if (firstPosition == 0) { 4362 mFirstPositionDistanceGuess = firstTop - listPadding.top; 4363 } else { 4364 mFirstPositionDistanceGuess += incrementalDeltaY; 4365 } 4366 if (firstPosition + childCount == mItemCount) { 4367 mLastPositionDistanceGuess = lastBottom + listPadding.bottom; 4368 } else { 4369 mLastPositionDistanceGuess += incrementalDeltaY; 4370 } 4371 4372 final boolean cannotScrollDown = (firstPosition == 0 && 4373 firstTop >= listPadding.top && incrementalDeltaY >= 0); 4374 final boolean cannotScrollUp = (firstPosition + childCount == mItemCount && 4375 lastBottom <= getHeight() - listPadding.bottom && incrementalDeltaY <= 0); 4376 4377 if (cannotScrollDown || cannotScrollUp) { 4378 return incrementalDeltaY != 0; 4379 } 4380 4381 final boolean down = incrementalDeltaY < 0; 4382 4383 final boolean inTouchMode = isInTouchMode(); 4384 if (inTouchMode) { 4385 hideSelector(); 4386 } 4387 4388 final int headerViewsCount = getHeaderViewsCount(); 4389 final int footerViewsStart = mItemCount - getFooterViewsCount(); 4390 4391 int start = 0; 4392 int count = 0; 4393 4394 if (down) { 4395 int top = -incrementalDeltaY; 4396 if ((mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK) { 4397 top += listPadding.top; 4398 } 4399 for (int i = 0; i < childCount; i++) { 4400 final View child = getChildAt(i); 4401 if (child.getBottom() >= top) { 4402 break; 4403 } else { 4404 count++; 4405 int position = firstPosition + i; 4406 if (position >= headerViewsCount && position < footerViewsStart) { 4407 mRecycler.addScrapView(child, position); 4408 4409 if (ViewDebug.TRACE_RECYCLER) { 4410 ViewDebug.trace(child, 4411 ViewDebug.RecyclerTraceType.MOVE_TO_SCRAP_HEAP, 4412 firstPosition + i, -1); 4413 } 4414 } 4415 } 4416 } 4417 } else { 4418 int bottom = getHeight() - incrementalDeltaY; 4419 if ((mGroupFlags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK) { 4420 bottom -= listPadding.bottom; 4421 } 4422 for (int i = childCount - 1; i >= 0; i--) { 4423 final View child = getChildAt(i); 4424 if (child.getTop() <= bottom) { 4425 break; 4426 } else { 4427 start = i; 4428 count++; 4429 int position = firstPosition + i; 4430 if (position >= headerViewsCount && position < footerViewsStart) { 4431 mRecycler.addScrapView(child, position); 4432 4433 if (ViewDebug.TRACE_RECYCLER) { 4434 ViewDebug.trace(child, 4435 ViewDebug.RecyclerTraceType.MOVE_TO_SCRAP_HEAP, 4436 firstPosition + i, -1); 4437 } 4438 } 4439 } 4440 } 4441 } 4442 4443 mMotionViewNewTop = mMotionViewOriginalTop + deltaY; 4444 4445 mBlockLayoutRequests = true; 4446 4447 if (count > 0) { 4448 detachViewsFromParent(start, count); 4449 } 4450 offsetChildrenTopAndBottom(incrementalDeltaY); 4451 4452 if (down) { 4453 mFirstPosition += count; 4454 } 4455 4456 invalidate(); 4457 4458 final int absIncrementalDeltaY = Math.abs(incrementalDeltaY); 4459 if (spaceAbove < absIncrementalDeltaY || spaceBelow < absIncrementalDeltaY) { 4460 fillGap(down); 4461 } 4462 4463 if (!inTouchMode && mSelectedPosition != INVALID_POSITION) { 4464 final int childIndex = mSelectedPosition - mFirstPosition; 4465 if (childIndex >= 0 && childIndex < getChildCount()) { 4466 positionSelector(mSelectedPosition, getChildAt(childIndex)); 4467 } 4468 } else if (mSelectorPosition != INVALID_POSITION) { 4469 final int childIndex = mSelectorPosition - mFirstPosition; 4470 if (childIndex >= 0 && childIndex < getChildCount()) { 4471 positionSelector(INVALID_POSITION, getChildAt(childIndex)); 4472 } 4473 } else { 4474 mSelectorRect.setEmpty(); 4475 } 4476 4477 mBlockLayoutRequests = false; 4478 4479 invokeOnItemScrollListener(); 4480 awakenScrollBars(); 4481 4482 return false; 4483 } 4484 4485 /** 4486 * Returns the number of header views in the list. Header views are special views 4487 * at the top of the list that should not be recycled during a layout. 4488 * 4489 * @return The number of header views, 0 in the default implementation. 4490 */ 4491 int getHeaderViewsCount() { 4492 return 0; 4493 } 4494 4495 /** 4496 * Returns the number of footer views in the list. Footer views are special views 4497 * at the bottom of the list that should not be recycled during a layout. 4498 * 4499 * @return The number of footer views, 0 in the default implementation. 4500 */ 4501 int getFooterViewsCount() { 4502 return 0; 4503 } 4504 4505 /** 4506 * Fills the gap left open by a touch-scroll. During a touch scroll, children that 4507 * remain on screen are shifted and the other ones are discarded. The role of this 4508 * method is to fill the gap thus created by performing a partial layout in the 4509 * empty space. 4510 * 4511 * @param down true if the scroll is going down, false if it is going up 4512 */ 4513 abstract void fillGap(boolean down); 4514 4515 void hideSelector() { 4516 if (mSelectedPosition != INVALID_POSITION) { 4517 if (mLayoutMode != LAYOUT_SPECIFIC) { 4518 mResurrectToPosition = mSelectedPosition; 4519 } 4520 if (mNextSelectedPosition >= 0 && mNextSelectedPosition != mSelectedPosition) { 4521 mResurrectToPosition = mNextSelectedPosition; 4522 } 4523 setSelectedPositionInt(INVALID_POSITION); 4524 setNextSelectedPositionInt(INVALID_POSITION); 4525 mSelectedTop = 0; 4526 } 4527 } 4528 4529 /** 4530 * @return A position to select. First we try mSelectedPosition. If that has been clobbered by 4531 * entering touch mode, we then try mResurrectToPosition. Values are pinned to the range 4532 * of items available in the adapter 4533 */ 4534 int reconcileSelectedPosition() { 4535 int position = mSelectedPosition; 4536 if (position < 0) { 4537 position = mResurrectToPosition; 4538 } 4539 position = Math.max(0, position); 4540 position = Math.min(position, mItemCount - 1); 4541 return position; 4542 } 4543 4544 /** 4545 * Find the row closest to y. This row will be used as the motion row when scrolling 4546 * 4547 * @param y Where the user touched 4548 * @return The position of the first (or only) item in the row containing y 4549 */ 4550 abstract int findMotionRow(int y); 4551 4552 /** 4553 * Find the row closest to y. This row will be used as the motion row when scrolling. 4554 * 4555 * @param y Where the user touched 4556 * @return The position of the first (or only) item in the row closest to y 4557 */ 4558 int findClosestMotionRow(int y) { 4559 final int childCount = getChildCount(); 4560 if (childCount == 0) { 4561 return INVALID_POSITION; 4562 } 4563 4564 final int motionRow = findMotionRow(y); 4565 return motionRow != INVALID_POSITION ? motionRow : mFirstPosition + childCount - 1; 4566 } 4567 4568 /** 4569 * Causes all the views to be rebuilt and redrawn. 4570 */ 4571 public void invalidateViews() { 4572 mDataChanged = true; 4573 rememberSyncState(); 4574 requestLayout(); 4575 invalidate(); 4576 } 4577 4578 /** 4579 * If there is a selection returns false. 4580 * Otherwise resurrects the selection and returns true if resurrected. 4581 */ 4582 boolean resurrectSelectionIfNeeded() { 4583 if (mSelectedPosition < 0 && resurrectSelection()) { 4584 updateSelectorState(); 4585 return true; 4586 } 4587 return false; 4588 } 4589 4590 /** 4591 * Makes the item at the supplied position selected. 4592 * 4593 * @param position the position of the new selection 4594 */ 4595 abstract void setSelectionInt(int position); 4596 4597 /** 4598 * Attempt to bring the selection back if the user is switching from touch 4599 * to trackball mode 4600 * @return Whether selection was set to something. 4601 */ 4602 boolean resurrectSelection() { 4603 final int childCount = getChildCount(); 4604 4605 if (childCount <= 0) { 4606 return false; 4607 } 4608 4609 int selectedTop = 0; 4610 int selectedPos; 4611 int childrenTop = mListPadding.top; 4612 int childrenBottom = mBottom - mTop - mListPadding.bottom; 4613 final int firstPosition = mFirstPosition; 4614 final int toPosition = mResurrectToPosition; 4615 boolean down = true; 4616 4617 if (toPosition >= firstPosition && toPosition < firstPosition + childCount) { 4618 selectedPos = toPosition; 4619 4620 final View selected = getChildAt(selectedPos - mFirstPosition); 4621 selectedTop = selected.getTop(); 4622 int selectedBottom = selected.getBottom(); 4623 4624 // We are scrolled, don't get in the fade 4625 if (selectedTop < childrenTop) { 4626 selectedTop = childrenTop + getVerticalFadingEdgeLength(); 4627 } else if (selectedBottom > childrenBottom) { 4628 selectedTop = childrenBottom - selected.getMeasuredHeight() 4629 - getVerticalFadingEdgeLength(); 4630 } 4631 } else { 4632 if (toPosition < firstPosition) { 4633 // Default to selecting whatever is first 4634 selectedPos = firstPosition; 4635 for (int i = 0; i < childCount; i++) { 4636 final View v = getChildAt(i); 4637 final int top = v.getTop(); 4638 4639 if (i == 0) { 4640 // Remember the position of the first item 4641 selectedTop = top; 4642 // See if we are scrolled at all 4643 if (firstPosition > 0 || top < childrenTop) { 4644 // If we are scrolled, don't select anything that is 4645 // in the fade region 4646 childrenTop += getVerticalFadingEdgeLength(); 4647 } 4648 } 4649 if (top >= childrenTop) { 4650 // Found a view whose top is fully visisble 4651 selectedPos = firstPosition + i; 4652 selectedTop = top; 4653 break; 4654 } 4655 } 4656 } else { 4657 final int itemCount = mItemCount; 4658 down = false; 4659 selectedPos = firstPosition + childCount - 1; 4660 4661 for (int i = childCount - 1; i >= 0; i--) { 4662 final View v = getChildAt(i); 4663 final int top = v.getTop(); 4664 final int bottom = v.getBottom(); 4665 4666 if (i == childCount - 1) { 4667 selectedTop = top; 4668 if (firstPosition + childCount < itemCount || bottom > childrenBottom) { 4669 childrenBottom -= getVerticalFadingEdgeLength(); 4670 } 4671 } 4672 4673 if (bottom <= childrenBottom) { 4674 selectedPos = firstPosition + i; 4675 selectedTop = top; 4676 break; 4677 } 4678 } 4679 } 4680 } 4681 4682 mResurrectToPosition = INVALID_POSITION; 4683 removeCallbacks(mFlingRunnable); 4684 if (mPositionScroller != null) { 4685 mPositionScroller.stop(); 4686 } 4687 mTouchMode = TOUCH_MODE_REST; 4688 clearScrollingCache(); 4689 mSpecificTop = selectedTop; 4690 selectedPos = lookForSelectablePosition(selectedPos, down); 4691 if (selectedPos >= firstPosition && selectedPos <= getLastVisiblePosition()) { 4692 mLayoutMode = LAYOUT_SPECIFIC; 4693 updateSelectorState(); 4694 setSelectionInt(selectedPos); 4695 invokeOnItemScrollListener(); 4696 } else { 4697 selectedPos = INVALID_POSITION; 4698 } 4699 reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE); 4700 4701 return selectedPos >= 0; 4702 } 4703 4704 @Override 4705 protected void handleDataChanged() { 4706 int count = mItemCount; 4707 if (count > 0) { 4708 4709 int newPos; 4710 4711 int selectablePos; 4712 4713 // Find the row we are supposed to sync to 4714 if (mNeedSync) { 4715 // Update this first, since setNextSelectedPositionInt inspects it 4716 mNeedSync = false; 4717 4718 if (mTranscriptMode == TRANSCRIPT_MODE_ALWAYS_SCROLL) { 4719 mLayoutMode = LAYOUT_FORCE_BOTTOM; 4720 return; 4721 } else if (mTranscriptMode == TRANSCRIPT_MODE_NORMAL) { 4722 if (mForceTranscriptScroll) { 4723 mForceTranscriptScroll = false; 4724 mLayoutMode = LAYOUT_FORCE_BOTTOM; 4725 return; 4726 } 4727 final int childCount = getChildCount(); 4728 final int listBottom = getBottom() - getPaddingBottom(); 4729 final View lastChild = getChildAt(childCount - 1); 4730 final int lastBottom = lastChild != null ? lastChild.getBottom() : listBottom; 4731 if (mFirstPosition + childCount >= mOldItemCount && lastBottom <= listBottom) { 4732 mLayoutMode = LAYOUT_FORCE_BOTTOM; 4733 return; 4734 } 4735 // Something new came in and we didn't scroll; give the user a clue that 4736 // there's something new. 4737 awakenScrollBars(); 4738 } 4739 4740 switch (mSyncMode) { 4741 case SYNC_SELECTED_POSITION: 4742 if (isInTouchMode()) { 4743 // We saved our state when not in touch mode. (We know this because 4744 // mSyncMode is SYNC_SELECTED_POSITION.) Now we are trying to 4745 // restore in touch mode. Just leave mSyncPosition as it is (possibly 4746 // adjusting if the available range changed) and return. 4747 mLayoutMode = LAYOUT_SYNC; 4748 mSyncPosition = Math.min(Math.max(0, mSyncPosition), count - 1); 4749 4750 return; 4751 } else { 4752 // See if we can find a position in the new data with the same 4753 // id as the old selection. This will change mSyncPosition. 4754 newPos = findSyncPosition(); 4755 if (newPos >= 0) { 4756 // Found it. Now verify that new selection is still selectable 4757 selectablePos = lookForSelectablePosition(newPos, true); 4758 if (selectablePos == newPos) { 4759 // Same row id is selected 4760 mSyncPosition = newPos; 4761 4762 if (mSyncHeight == getHeight()) { 4763 // If we are at the same height as when we saved state, try 4764 // to restore the scroll position too. 4765 mLayoutMode = LAYOUT_SYNC; 4766 } else { 4767 // We are not the same height as when the selection was saved, so 4768 // don't try to restore the exact position 4769 mLayoutMode = LAYOUT_SET_SELECTION; 4770 } 4771 4772 // Restore selection 4773 setNextSelectedPositionInt(newPos); 4774 return; 4775 } 4776 } 4777 } 4778 break; 4779 case SYNC_FIRST_POSITION: 4780 // Leave mSyncPosition as it is -- just pin to available range 4781 mLayoutMode = LAYOUT_SYNC; 4782 mSyncPosition = Math.min(Math.max(0, mSyncPosition), count - 1); 4783 4784 return; 4785 } 4786 } 4787 4788 if (!isInTouchMode()) { 4789 // We couldn't find matching data -- try to use the same position 4790 newPos = getSelectedItemPosition(); 4791 4792 // Pin position to the available range 4793 if (newPos >= count) { 4794 newPos = count - 1; 4795 } 4796 if (newPos < 0) { 4797 newPos = 0; 4798 } 4799 4800 // Make sure we select something selectable -- first look down 4801 selectablePos = lookForSelectablePosition(newPos, true); 4802 4803 if (selectablePos >= 0) { 4804 setNextSelectedPositionInt(selectablePos); 4805 return; 4806 } else { 4807 // Looking down didn't work -- try looking up 4808 selectablePos = lookForSelectablePosition(newPos, false); 4809 if (selectablePos >= 0) { 4810 setNextSelectedPositionInt(selectablePos); 4811 return; 4812 } 4813 } 4814 } else { 4815 4816 // We already know where we want to resurrect the selection 4817 if (mResurrectToPosition >= 0) { 4818 return; 4819 } 4820 } 4821 4822 } 4823 4824 // Nothing is selected. Give up and reset everything. 4825 mLayoutMode = mStackFromBottom ? LAYOUT_FORCE_BOTTOM : LAYOUT_FORCE_TOP; 4826 mSelectedPosition = INVALID_POSITION; 4827 mSelectedRowId = INVALID_ROW_ID; 4828 mNextSelectedPosition = INVALID_POSITION; 4829 mNextSelectedRowId = INVALID_ROW_ID; 4830 mNeedSync = false; 4831 mSelectorPosition = INVALID_POSITION; 4832 checkSelectionChanged(); 4833 } 4834 4835 @Override 4836 protected void onDisplayHint(int hint) { 4837 super.onDisplayHint(hint); 4838 switch (hint) { 4839 case INVISIBLE: 4840 if (mPopup != null && mPopup.isShowing()) { 4841 dismissPopup(); 4842 } 4843 break; 4844 case VISIBLE: 4845 if (mFiltered && mPopup != null && !mPopup.isShowing()) { 4846 showPopup(); 4847 } 4848 break; 4849 } 4850 mPopupHidden = hint == INVISIBLE; 4851 } 4852 4853 /** 4854 * Removes the filter window 4855 */ 4856 private void dismissPopup() { 4857 if (mPopup != null) { 4858 mPopup.dismiss(); 4859 } 4860 } 4861 4862 /** 4863 * Shows the filter window 4864 */ 4865 private void showPopup() { 4866 // Make sure we have a window before showing the popup 4867 if (getWindowVisibility() == View.VISIBLE) { 4868 createTextFilter(true); 4869 positionPopup(); 4870 // Make sure we get focus if we are showing the popup 4871 checkFocus(); 4872 } 4873 } 4874 4875 private void positionPopup() { 4876 int screenHeight = getResources().getDisplayMetrics().heightPixels; 4877 final int[] xy = new int[2]; 4878 getLocationOnScreen(xy); 4879 // TODO: The 20 below should come from the theme 4880 // TODO: And the gravity should be defined in the theme as well 4881 final int bottomGap = screenHeight - xy[1] - getHeight() + (int) (mDensityScale * 20); 4882 if (!mPopup.isShowing()) { 4883 mPopup.showAtLocation(this, Gravity.BOTTOM | Gravity.CENTER_HORIZONTAL, 4884 xy[0], bottomGap); 4885 } else { 4886 mPopup.update(xy[0], bottomGap, -1, -1); 4887 } 4888 } 4889 4890 /** 4891 * What is the distance between the source and destination rectangles given the direction of 4892 * focus navigation between them? The direction basically helps figure out more quickly what is 4893 * self evident by the relationship between the rects... 4894 * 4895 * @param source the source rectangle 4896 * @param dest the destination rectangle 4897 * @param direction the direction 4898 * @return the distance between the rectangles 4899 */ 4900 static int getDistance(Rect source, Rect dest, int direction) { 4901 int sX, sY; // source x, y 4902 int dX, dY; // dest x, y 4903 switch (direction) { 4904 case View.FOCUS_RIGHT: 4905 sX = source.right; 4906 sY = source.top + source.height() / 2; 4907 dX = dest.left; 4908 dY = dest.top + dest.height() / 2; 4909 break; 4910 case View.FOCUS_DOWN: 4911 sX = source.left + source.width() / 2; 4912 sY = source.bottom; 4913 dX = dest.left + dest.width() / 2; 4914 dY = dest.top; 4915 break; 4916 case View.FOCUS_LEFT: 4917 sX = source.left; 4918 sY = source.top + source.height() / 2; 4919 dX = dest.right; 4920 dY = dest.top + dest.height() / 2; 4921 break; 4922 case View.FOCUS_UP: 4923 sX = source.left + source.width() / 2; 4924 sY = source.top; 4925 dX = dest.left + dest.width() / 2; 4926 dY = dest.bottom; 4927 break; 4928 case View.FOCUS_FORWARD: 4929 case View.FOCUS_BACKWARD: 4930 sX = source.right + source.width() / 2; 4931 sY = source.top + source.height() / 2; 4932 dX = dest.left + dest.width() / 2; 4933 dY = dest.top + dest.height() / 2; 4934 break; 4935 default: 4936 throw new IllegalArgumentException("direction must be one of " 4937 + "{FOCUS_UP, FOCUS_DOWN, FOCUS_LEFT, FOCUS_RIGHT, " 4938 + "FOCUS_FORWARD, FOCUS_BACKWARD}."); 4939 } 4940 int deltaX = dX - sX; 4941 int deltaY = dY - sY; 4942 return deltaY * deltaY + deltaX * deltaX; 4943 } 4944 4945 @Override 4946 protected boolean isInFilterMode() { 4947 return mFiltered; 4948 } 4949 4950 /** 4951 * Sends a key to the text filter window 4952 * 4953 * @param keyCode The keycode for the event 4954 * @param event The actual key event 4955 * 4956 * @return True if the text filter handled the event, false otherwise. 4957 */ 4958 boolean sendToTextFilter(int keyCode, int count, KeyEvent event) { 4959 if (!acceptFilter()) { 4960 return false; 4961 } 4962 4963 boolean handled = false; 4964 boolean okToSend = true; 4965 switch (keyCode) { 4966 case KeyEvent.KEYCODE_DPAD_UP: 4967 case KeyEvent.KEYCODE_DPAD_DOWN: 4968 case KeyEvent.KEYCODE_DPAD_LEFT: 4969 case KeyEvent.KEYCODE_DPAD_RIGHT: 4970 case KeyEvent.KEYCODE_DPAD_CENTER: 4971 case KeyEvent.KEYCODE_ENTER: 4972 okToSend = false; 4973 break; 4974 case KeyEvent.KEYCODE_BACK: 4975 if (mFiltered && mPopup != null && mPopup.isShowing()) { 4976 if (event.getAction() == KeyEvent.ACTION_DOWN 4977 && event.getRepeatCount() == 0) { 4978 KeyEvent.DispatcherState state = getKeyDispatcherState(); 4979 if (state != null) { 4980 state.startTracking(event, this); 4981 } 4982 handled = true; 4983 } else if (event.getAction() == KeyEvent.ACTION_UP 4984 && event.isTracking() && !event.isCanceled()) { 4985 handled = true; 4986 mTextFilter.setText(""); 4987 } 4988 } 4989 okToSend = false; 4990 break; 4991 case KeyEvent.KEYCODE_SPACE: 4992 // Only send spaces once we are filtered 4993 okToSend = mFiltered; 4994 break; 4995 } 4996 4997 if (okToSend) { 4998 createTextFilter(true); 4999 5000 KeyEvent forwardEvent = event; 5001 if (forwardEvent.getRepeatCount() > 0) { 5002 forwardEvent = KeyEvent.changeTimeRepeat(event, event.getEventTime(), 0); 5003 } 5004 5005 int action = event.getAction(); 5006 switch (action) { 5007 case KeyEvent.ACTION_DOWN: 5008 handled = mTextFilter.onKeyDown(keyCode, forwardEvent); 5009 break; 5010 5011 case KeyEvent.ACTION_UP: 5012 handled = mTextFilter.onKeyUp(keyCode, forwardEvent); 5013 break; 5014 5015 case KeyEvent.ACTION_MULTIPLE: 5016 handled = mTextFilter.onKeyMultiple(keyCode, count, event); 5017 break; 5018 } 5019 } 5020 return handled; 5021 } 5022 5023 /** 5024 * Return an InputConnection for editing of the filter text. 5025 */ 5026 @Override 5027 public InputConnection onCreateInputConnection(EditorInfo outAttrs) { 5028 if (isTextFilterEnabled()) { 5029 // XXX we need to have the text filter created, so we can get an 5030 // InputConnection to proxy to. Unfortunately this means we pretty 5031 // much need to make it as soon as a list view gets focus. 5032 createTextFilter(false); 5033 if (mPublicInputConnection == null) { 5034 mDefInputConnection = new BaseInputConnection(this, false); 5035 mPublicInputConnection = new InputConnectionWrapper( 5036 mTextFilter.onCreateInputConnection(outAttrs), true) { 5037 @Override 5038 public boolean reportFullscreenMode(boolean enabled) { 5039 // Use our own input connection, since it is 5040 // the "real" one the IME is talking with. 5041 return mDefInputConnection.reportFullscreenMode(enabled); 5042 } 5043 5044 @Override 5045 public boolean performEditorAction(int editorAction) { 5046 // The editor is off in its own window; we need to be 5047 // the one that does this. 5048 if (editorAction == EditorInfo.IME_ACTION_DONE) { 5049 InputMethodManager imm = (InputMethodManager) 5050 getContext().getSystemService( 5051 Context.INPUT_METHOD_SERVICE); 5052 if (imm != null) { 5053 imm.hideSoftInputFromWindow(getWindowToken(), 0); 5054 } 5055 return true; 5056 } 5057 return false; 5058 } 5059 5060 @Override 5061 public boolean sendKeyEvent(KeyEvent event) { 5062 // Use our own input connection, since the filter 5063 // text view may not be shown in a window so has 5064 // no ViewAncestor to dispatch events with. 5065 return mDefInputConnection.sendKeyEvent(event); 5066 } 5067 }; 5068 } 5069 outAttrs.inputType = EditorInfo.TYPE_CLASS_TEXT 5070 | EditorInfo.TYPE_TEXT_VARIATION_FILTER; 5071 outAttrs.imeOptions = EditorInfo.IME_ACTION_DONE; 5072 return mPublicInputConnection; 5073 } 5074 return null; 5075 } 5076 5077 /** 5078 * For filtering we proxy an input connection to an internal text editor, 5079 * and this allows the proxying to happen. 5080 */ 5081 @Override 5082 public boolean checkInputConnectionProxy(View view) { 5083 return view == mTextFilter; 5084 } 5085 5086 /** 5087 * Creates the window for the text filter and populates it with an EditText field; 5088 * 5089 * @param animateEntrance true if the window should appear with an animation 5090 */ 5091 private void createTextFilter(boolean animateEntrance) { 5092 if (mPopup == null) { 5093 Context c = getContext(); 5094 PopupWindow p = new PopupWindow(c); 5095 LayoutInflater layoutInflater = (LayoutInflater) 5096 c.getSystemService(Context.LAYOUT_INFLATER_SERVICE); 5097 mTextFilter = (EditText) layoutInflater.inflate( 5098 com.android.internal.R.layout.typing_filter, null); 5099 // For some reason setting this as the "real" input type changes 5100 // the text view in some way that it doesn't work, and I don't 5101 // want to figure out why this is. 5102 mTextFilter.setRawInputType(EditorInfo.TYPE_CLASS_TEXT 5103 | EditorInfo.TYPE_TEXT_VARIATION_FILTER); 5104 mTextFilter.setImeOptions(EditorInfo.IME_FLAG_NO_EXTRACT_UI); 5105 mTextFilter.addTextChangedListener(this); 5106 p.setFocusable(false); 5107 p.setTouchable(false); 5108 p.setInputMethodMode(PopupWindow.INPUT_METHOD_NOT_NEEDED); 5109 p.setContentView(mTextFilter); 5110 p.setWidth(LayoutParams.WRAP_CONTENT); 5111 p.setHeight(LayoutParams.WRAP_CONTENT); 5112 p.setBackgroundDrawable(null); 5113 mPopup = p; 5114 getViewTreeObserver().addOnGlobalLayoutListener(this); 5115 mGlobalLayoutListenerAddedFilter = true; 5116 } 5117 if (animateEntrance) { 5118 mPopup.setAnimationStyle(com.android.internal.R.style.Animation_TypingFilter); 5119 } else { 5120 mPopup.setAnimationStyle(com.android.internal.R.style.Animation_TypingFilterRestore); 5121 } 5122 } 5123 5124 /** 5125 * Clear the text filter. 5126 */ 5127 public void clearTextFilter() { 5128 if (mFiltered) { 5129 mTextFilter.setText(""); 5130 mFiltered = false; 5131 if (mPopup != null && mPopup.isShowing()) { 5132 dismissPopup(); 5133 } 5134 } 5135 } 5136 5137 /** 5138 * Returns if the ListView currently has a text filter. 5139 */ 5140 public boolean hasTextFilter() { 5141 return mFiltered; 5142 } 5143 5144 public void onGlobalLayout() { 5145 if (isShown()) { 5146 // Show the popup if we are filtered 5147 if (mFiltered && mPopup != null && !mPopup.isShowing() && !mPopupHidden) { 5148 showPopup(); 5149 } 5150 } else { 5151 // Hide the popup when we are no longer visible 5152 if (mPopup != null && mPopup.isShowing()) { 5153 dismissPopup(); 5154 } 5155 } 5156 5157 } 5158 5159 /** 5160 * For our text watcher that is associated with the text filter. Does 5161 * nothing. 5162 */ 5163 public void beforeTextChanged(CharSequence s, int start, int count, int after) { 5164 } 5165 5166 /** 5167 * For our text watcher that is associated with the text filter. Performs 5168 * the actual filtering as the text changes, and takes care of hiding and 5169 * showing the popup displaying the currently entered filter text. 5170 */ 5171 public void onTextChanged(CharSequence s, int start, int before, int count) { 5172 if (mPopup != null && isTextFilterEnabled()) { 5173 int length = s.length(); 5174 boolean showing = mPopup.isShowing(); 5175 if (!showing && length > 0) { 5176 // Show the filter popup if necessary 5177 showPopup(); 5178 mFiltered = true; 5179 } else if (showing && length == 0) { 5180 // Remove the filter popup if the user has cleared all text 5181 dismissPopup(); 5182 mFiltered = false; 5183 } 5184 if (mAdapter instanceof Filterable) { 5185 Filter f = ((Filterable) mAdapter).getFilter(); 5186 // Filter should not be null when we reach this part 5187 if (f != null) { 5188 f.filter(s, this); 5189 } else { 5190 throw new IllegalStateException("You cannot call onTextChanged with a non " 5191 + "filterable adapter"); 5192 } 5193 } 5194 } 5195 } 5196 5197 /** 5198 * For our text watcher that is associated with the text filter. Does 5199 * nothing. 5200 */ 5201 public void afterTextChanged(Editable s) { 5202 } 5203 5204 public void onFilterComplete(int count) { 5205 if (mSelectedPosition < 0 && count > 0) { 5206 mResurrectToPosition = INVALID_POSITION; 5207 resurrectSelection(); 5208 } 5209 } 5210 5211 @Override 5212 protected ViewGroup.LayoutParams generateLayoutParams(ViewGroup.LayoutParams p) { 5213 return new LayoutParams(p); 5214 } 5215 5216 @Override 5217 public LayoutParams generateLayoutParams(AttributeSet attrs) { 5218 return new AbsListView.LayoutParams(getContext(), attrs); 5219 } 5220 5221 @Override 5222 protected boolean checkLayoutParams(ViewGroup.LayoutParams p) { 5223 return p instanceof AbsListView.LayoutParams; 5224 } 5225 5226 /** 5227 * Puts the list or grid into transcript mode. In this mode the list or grid will always scroll 5228 * to the bottom to show new items. 5229 * 5230 * @param mode the transcript mode to set 5231 * 5232 * @see #TRANSCRIPT_MODE_DISABLED 5233 * @see #TRANSCRIPT_MODE_NORMAL 5234 * @see #TRANSCRIPT_MODE_ALWAYS_SCROLL 5235 */ 5236 public void setTranscriptMode(int mode) { 5237 mTranscriptMode = mode; 5238 } 5239 5240 /** 5241 * Returns the current transcript mode. 5242 * 5243 * @return {@link #TRANSCRIPT_MODE_DISABLED}, {@link #TRANSCRIPT_MODE_NORMAL} or 5244 * {@link #TRANSCRIPT_MODE_ALWAYS_SCROLL} 5245 */ 5246 public int getTranscriptMode() { 5247 return mTranscriptMode; 5248 } 5249 5250 @Override 5251 public int getSolidColor() { 5252 return mCacheColorHint; 5253 } 5254 5255 /** 5256 * When set to a non-zero value, the cache color hint indicates that this list is always drawn 5257 * on top of a solid, single-color, opaque background. 5258 * 5259 * Zero means that what's behind this object is translucent (non solid) or is not made of a 5260 * single color. This hint will not affect any existing background drawable set on this view ( 5261 * typically set via {@link #setBackgroundDrawable(Drawable)}). 5262 * 5263 * @param color The background color 5264 */ 5265 public void setCacheColorHint(int color) { 5266 if (color != mCacheColorHint) { 5267 mCacheColorHint = color; 5268 int count = getChildCount(); 5269 for (int i = 0; i < count; i++) { 5270 getChildAt(i).setDrawingCacheBackgroundColor(color); 5271 } 5272 mRecycler.setCacheColorHint(color); 5273 } 5274 } 5275 5276 /** 5277 * When set to a non-zero value, the cache color hint indicates that this list is always drawn 5278 * on top of a solid, single-color, opaque background 5279 * 5280 * @return The cache color hint 5281 */ 5282 @ViewDebug.ExportedProperty(category = "drawing") 5283 public int getCacheColorHint() { 5284 return mCacheColorHint; 5285 } 5286 5287 /** 5288 * Move all views (excluding headers and footers) held by this AbsListView into the supplied 5289 * List. This includes views displayed on the screen as well as views stored in AbsListView's 5290 * internal view recycler. 5291 * 5292 * @param views A list into which to put the reclaimed views 5293 */ 5294 public void reclaimViews(List<View> views) { 5295 int childCount = getChildCount(); 5296 RecyclerListener listener = mRecycler.mRecyclerListener; 5297 5298 // Reclaim views on screen 5299 for (int i = 0; i < childCount; i++) { 5300 View child = getChildAt(i); 5301 AbsListView.LayoutParams lp = (AbsListView.LayoutParams) child.getLayoutParams(); 5302 // Don't reclaim header or footer views, or views that should be ignored 5303 if (lp != null && mRecycler.shouldRecycleViewType(lp.viewType)) { 5304 views.add(child); 5305 if (listener != null) { 5306 // Pretend they went through the scrap heap 5307 listener.onMovedToScrapHeap(child); 5308 } 5309 } 5310 } 5311 mRecycler.reclaimScrapViews(views); 5312 removeAllViewsInLayout(); 5313 } 5314 5315 /** 5316 * @hide 5317 */ 5318 @Override 5319 protected boolean onConsistencyCheck(int consistency) { 5320 boolean result = super.onConsistencyCheck(consistency); 5321 5322 final boolean checkLayout = (consistency & ViewDebug.CONSISTENCY_LAYOUT) != 0; 5323 5324 if (checkLayout) { 5325 // The active recycler must be empty 5326 final View[] activeViews = mRecycler.mActiveViews; 5327 int count = activeViews.length; 5328 for (int i = 0; i < count; i++) { 5329 if (activeViews[i] != null) { 5330 result = false; 5331 Log.d(ViewDebug.CONSISTENCY_LOG_TAG, 5332 "AbsListView " + this + " has a view in its active recycler: " + 5333 activeViews[i]); 5334 } 5335 } 5336 5337 // All views in the recycler must NOT be on screen and must NOT have a parent 5338 final ArrayList<View> scrap = mRecycler.mCurrentScrap; 5339 if (!checkScrap(scrap)) result = false; 5340 final ArrayList<View>[] scraps = mRecycler.mScrapViews; 5341 count = scraps.length; 5342 for (int i = 0; i < count; i++) { 5343 if (!checkScrap(scraps[i])) result = false; 5344 } 5345 } 5346 5347 return result; 5348 } 5349 5350 private boolean checkScrap(ArrayList<View> scrap) { 5351 if (scrap == null) return true; 5352 boolean result = true; 5353 5354 final int count = scrap.size(); 5355 for (int i = 0; i < count; i++) { 5356 final View view = scrap.get(i); 5357 if (view.getParent() != null) { 5358 result = false; 5359 Log.d(ViewDebug.CONSISTENCY_LOG_TAG, "AbsListView " + this + 5360 " has a view in its scrap heap still attached to a parent: " + view); 5361 } 5362 if (indexOfChild(view) >= 0) { 5363 result = false; 5364 Log.d(ViewDebug.CONSISTENCY_LOG_TAG, "AbsListView " + this + 5365 " has a view in its scrap heap that is also a direct child: " + view); 5366 } 5367 } 5368 5369 return result; 5370 } 5371 5372 private void finishGlows() { 5373 if (mEdgeGlowTop != null) { 5374 mEdgeGlowTop.finish(); 5375 mEdgeGlowBottom.finish(); 5376 } 5377 } 5378 5379 /** 5380 * Sets up this AbsListView to use a remote views adapter which connects to a RemoteViewsService 5381 * through the specified intent. 5382 * @param intent the intent used to identify the RemoteViewsService for the adapter to connect to. 5383 */ 5384 public void setRemoteViewsAdapter(Intent intent) { 5385 // Ensure that we don't already have a RemoteViewsAdapter that is bound to an existing 5386 // service handling the specified intent. 5387 if (mRemoteAdapter != null) { 5388 Intent.FilterComparison fcNew = new Intent.FilterComparison(intent); 5389 Intent.FilterComparison fcOld = new Intent.FilterComparison( 5390 mRemoteAdapter.getRemoteViewsServiceIntent()); 5391 if (fcNew.equals(fcOld)) { 5392 return; 5393 } 5394 } 5395 5396 // Otherwise, create a new RemoteViewsAdapter for binding 5397 mRemoteAdapter = new RemoteViewsAdapter(getContext(), intent, this); 5398 } 5399 5400 /** 5401 * Called back when the adapter connects to the RemoteViewsService. 5402 */ 5403 public boolean onRemoteAdapterConnected() { 5404 if (mRemoteAdapter != mAdapter) { 5405 setAdapter(mRemoteAdapter); 5406 return false; 5407 } else if (mRemoteAdapter != null) { 5408 mRemoteAdapter.superNotifyDataSetChanged(); 5409 return true; 5410 } 5411 return false; 5412 } 5413 5414 /** 5415 * Called back when the adapter disconnects from the RemoteViewsService. 5416 */ 5417 public void onRemoteAdapterDisconnected() { 5418 // If the remote adapter disconnects, we keep it around 5419 // since the currently displayed items are still cached. 5420 // Further, we want the service to eventually reconnect 5421 // when necessary, as triggered by this view requesting 5422 // items from the Adapter. 5423 } 5424 5425 /** 5426 * Sets the recycler listener to be notified whenever a View is set aside in 5427 * the recycler for later reuse. This listener can be used to free resources 5428 * associated to the View. 5429 * 5430 * @param listener The recycler listener to be notified of views set aside 5431 * in the recycler. 5432 * 5433 * @see android.widget.AbsListView.RecycleBin 5434 * @see android.widget.AbsListView.RecyclerListener 5435 */ 5436 public void setRecyclerListener(RecyclerListener listener) { 5437 mRecycler.mRecyclerListener = listener; 5438 } 5439 5440 class AdapterDataSetObserver extends AdapterView<ListAdapter>.AdapterDataSetObserver { 5441 @Override 5442 public void onChanged() { 5443 super.onChanged(); 5444 if (mFastScroller != null) { 5445 mFastScroller.onSectionsChanged(); 5446 } 5447 } 5448 5449 @Override 5450 public void onInvalidated() { 5451 super.onInvalidated(); 5452 if (mFastScroller != null) { 5453 mFastScroller.onSectionsChanged(); 5454 } 5455 } 5456 } 5457 5458 /** 5459 * A MultiChoiceModeListener receives events for {@link AbsListView#CHOICE_MODE_MULTIPLE_MODAL}. 5460 * It acts as the {@link ActionMode.Callback} for the selection mode and also receives 5461 * {@link #onItemCheckedStateChanged(ActionMode, int, long, boolean)} events when the user 5462 * selects and deselects list items. 5463 */ 5464 public interface MultiChoiceModeListener extends ActionMode.Callback { 5465 /** 5466 * Called when an item is checked or unchecked during selection mode. 5467 * 5468 * @param mode The {@link ActionMode} providing the selection mode 5469 * @param position Adapter position of the item that was checked or unchecked 5470 * @param id Adapter ID of the item that was checked or unchecked 5471 * @param checked <code>true</code> if the item is now checked, <code>false</code> 5472 * if the item is now unchecked. 5473 */ 5474 public void onItemCheckedStateChanged(ActionMode mode, 5475 int position, long id, boolean checked); 5476 } 5477 5478 class MultiChoiceModeWrapper implements MultiChoiceModeListener { 5479 private MultiChoiceModeListener mWrapped; 5480 5481 public void setWrapped(MultiChoiceModeListener wrapped) { 5482 mWrapped = wrapped; 5483 } 5484 5485 public boolean onCreateActionMode(ActionMode mode, Menu menu) { 5486 if (mWrapped.onCreateActionMode(mode, menu)) { 5487 // Initialize checked graphic state? 5488 setLongClickable(false); 5489 return true; 5490 } 5491 return false; 5492 } 5493 5494 public boolean onPrepareActionMode(ActionMode mode, Menu menu) { 5495 return mWrapped.onPrepareActionMode(mode, menu); 5496 } 5497 5498 public boolean onActionItemClicked(ActionMode mode, MenuItem item) { 5499 return mWrapped.onActionItemClicked(mode, item); 5500 } 5501 5502 public void onDestroyActionMode(ActionMode mode) { 5503 mWrapped.onDestroyActionMode(mode); 5504 mChoiceActionMode = null; 5505 5506 // Ending selection mode means deselecting everything. 5507 clearChoices(); 5508 5509 mDataChanged = true; 5510 rememberSyncState(); 5511 requestLayout(); 5512 5513 setLongClickable(true); 5514 } 5515 5516 public void onItemCheckedStateChanged(ActionMode mode, 5517 int position, long id, boolean checked) { 5518 mWrapped.onItemCheckedStateChanged(mode, position, id, checked); 5519 5520 // If there are no items selected we no longer need the selection mode. 5521 if (getCheckedItemCount() == 0) { 5522 mode.finish(); 5523 } 5524 } 5525 } 5526 5527 /** 5528 * AbsListView extends LayoutParams to provide a place to hold the view type. 5529 */ 5530 public static class LayoutParams extends ViewGroup.LayoutParams { 5531 /** 5532 * View type for this view, as returned by 5533 * {@link android.widget.Adapter#getItemViewType(int) } 5534 */ 5535 @ViewDebug.ExportedProperty(category = "list", mapping = { 5536 @ViewDebug.IntToString(from = ITEM_VIEW_TYPE_IGNORE, to = "ITEM_VIEW_TYPE_IGNORE"), 5537 @ViewDebug.IntToString(from = ITEM_VIEW_TYPE_HEADER_OR_FOOTER, to = "ITEM_VIEW_TYPE_HEADER_OR_FOOTER") 5538 }) 5539 int viewType; 5540 5541 /** 5542 * When this boolean is set, the view has been added to the AbsListView 5543 * at least once. It is used to know whether headers/footers have already 5544 * been added to the list view and whether they should be treated as 5545 * recycled views or not. 5546 */ 5547 @ViewDebug.ExportedProperty(category = "list") 5548 boolean recycledHeaderFooter; 5549 5550 /** 5551 * When an AbsListView is measured with an AT_MOST measure spec, it needs 5552 * to obtain children views to measure itself. When doing so, the children 5553 * are not attached to the window, but put in the recycler which assumes 5554 * they've been attached before. Setting this flag will force the reused 5555 * view to be attached to the window rather than just attached to the 5556 * parent. 5557 */ 5558 @ViewDebug.ExportedProperty(category = "list") 5559 boolean forceAdd; 5560 5561 /** 5562 * The position the view was removed from when pulled out of the 5563 * scrap heap. 5564 * @hide 5565 */ 5566 int scrappedFromPosition; 5567 5568 public LayoutParams(Context c, AttributeSet attrs) { 5569 super(c, attrs); 5570 } 5571 5572 public LayoutParams(int w, int h) { 5573 super(w, h); 5574 } 5575 5576 public LayoutParams(int w, int h, int viewType) { 5577 super(w, h); 5578 this.viewType = viewType; 5579 } 5580 5581 public LayoutParams(ViewGroup.LayoutParams source) { 5582 super(source); 5583 } 5584 } 5585 5586 /** 5587 * A RecyclerListener is used to receive a notification whenever a View is placed 5588 * inside the RecycleBin's scrap heap. This listener is used to free resources 5589 * associated to Views placed in the RecycleBin. 5590 * 5591 * @see android.widget.AbsListView.RecycleBin 5592 * @see android.widget.AbsListView#setRecyclerListener(android.widget.AbsListView.RecyclerListener) 5593 */ 5594 public static interface RecyclerListener { 5595 /** 5596 * Indicates that the specified View was moved into the recycler's scrap heap. 5597 * The view is not displayed on screen any more and any expensive resource 5598 * associated with the view should be discarded. 5599 * 5600 * @param view 5601 */ 5602 void onMovedToScrapHeap(View view); 5603 } 5604 5605 /** 5606 * The RecycleBin facilitates reuse of views across layouts. The RecycleBin has two levels of 5607 * storage: ActiveViews and ScrapViews. ActiveViews are those views which were onscreen at the 5608 * start of a layout. By construction, they are displaying current information. At the end of 5609 * layout, all views in ActiveViews are demoted to ScrapViews. ScrapViews are old views that 5610 * could potentially be used by the adapter to avoid allocating views unnecessarily. 5611 * 5612 * @see android.widget.AbsListView#setRecyclerListener(android.widget.AbsListView.RecyclerListener) 5613 * @see android.widget.AbsListView.RecyclerListener 5614 */ 5615 class RecycleBin { 5616 private RecyclerListener mRecyclerListener; 5617 5618 /** 5619 * The position of the first view stored in mActiveViews. 5620 */ 5621 private int mFirstActivePosition; 5622 5623 /** 5624 * Views that were on screen at the start of layout. This array is populated at the start of 5625 * layout, and at the end of layout all view in mActiveViews are moved to mScrapViews. 5626 * Views in mActiveViews represent a contiguous range of Views, with position of the first 5627 * view store in mFirstActivePosition. 5628 */ 5629 private View[] mActiveViews = new View[0]; 5630 5631 /** 5632 * Unsorted views that can be used by the adapter as a convert view. 5633 */ 5634 private ArrayList<View>[] mScrapViews; 5635 5636 private int mViewTypeCount; 5637 5638 private ArrayList<View> mCurrentScrap; 5639 5640 public void setViewTypeCount(int viewTypeCount) { 5641 if (viewTypeCount < 1) { 5642 throw new IllegalArgumentException("Can't have a viewTypeCount < 1"); 5643 } 5644 //noinspection unchecked 5645 ArrayList<View>[] scrapViews = new ArrayList[viewTypeCount]; 5646 for (int i = 0; i < viewTypeCount; i++) { 5647 scrapViews[i] = new ArrayList<View>(); 5648 } 5649 mViewTypeCount = viewTypeCount; 5650 mCurrentScrap = scrapViews[0]; 5651 mScrapViews = scrapViews; 5652 } 5653 5654 public void markChildrenDirty() { 5655 if (mViewTypeCount == 1) { 5656 final ArrayList<View> scrap = mCurrentScrap; 5657 final int scrapCount = scrap.size(); 5658 for (int i = 0; i < scrapCount; i++) { 5659 scrap.get(i).forceLayout(); 5660 } 5661 } else { 5662 final int typeCount = mViewTypeCount; 5663 for (int i = 0; i < typeCount; i++) { 5664 final ArrayList<View> scrap = mScrapViews[i]; 5665 final int scrapCount = scrap.size(); 5666 for (int j = 0; j < scrapCount; j++) { 5667 scrap.get(j).forceLayout(); 5668 } 5669 } 5670 } 5671 } 5672 5673 public boolean shouldRecycleViewType(int viewType) { 5674 return viewType >= 0; 5675 } 5676 5677 /** 5678 * Clears the scrap heap. 5679 */ 5680 void clear() { 5681 if (mViewTypeCount == 1) { 5682 final ArrayList<View> scrap = mCurrentScrap; 5683 final int scrapCount = scrap.size(); 5684 for (int i = 0; i < scrapCount; i++) { 5685 removeDetachedView(scrap.remove(scrapCount - 1 - i), false); 5686 } 5687 } else { 5688 final int typeCount = mViewTypeCount; 5689 for (int i = 0; i < typeCount; i++) { 5690 final ArrayList<View> scrap = mScrapViews[i]; 5691 final int scrapCount = scrap.size(); 5692 for (int j = 0; j < scrapCount; j++) { 5693 removeDetachedView(scrap.remove(scrapCount - 1 - j), false); 5694 } 5695 } 5696 } 5697 } 5698 5699 /** 5700 * Fill ActiveViews with all of the children of the AbsListView. 5701 * 5702 * @param childCount The minimum number of views mActiveViews should hold 5703 * @param firstActivePosition The position of the first view that will be stored in 5704 * mActiveViews 5705 */ 5706 void fillActiveViews(int childCount, int firstActivePosition) { 5707 if (mActiveViews.length < childCount) { 5708 mActiveViews = new View[childCount]; 5709 } 5710 mFirstActivePosition = firstActivePosition; 5711 5712 final View[] activeViews = mActiveViews; 5713 for (int i = 0; i < childCount; i++) { 5714 View child = getChildAt(i); 5715 AbsListView.LayoutParams lp = (AbsListView.LayoutParams) child.getLayoutParams(); 5716 // Don't put header or footer views into the scrap heap 5717 if (lp != null && lp.viewType != ITEM_VIEW_TYPE_HEADER_OR_FOOTER) { 5718 // Note: We do place AdapterView.ITEM_VIEW_TYPE_IGNORE in active views. 5719 // However, we will NOT place them into scrap views. 5720 activeViews[i] = child; 5721 } 5722 } 5723 } 5724 5725 /** 5726 * Get the view corresponding to the specified position. The view will be removed from 5727 * mActiveViews if it is found. 5728 * 5729 * @param position The position to look up in mActiveViews 5730 * @return The view if it is found, null otherwise 5731 */ 5732 View getActiveView(int position) { 5733 int index = position - mFirstActivePosition; 5734 final View[] activeViews = mActiveViews; 5735 if (index >=0 && index < activeViews.length) { 5736 final View match = activeViews[index]; 5737 activeViews[index] = null; 5738 return match; 5739 } 5740 return null; 5741 } 5742 5743 /** 5744 * @return A view from the ScrapViews collection. These are unordered. 5745 */ 5746 View getScrapView(int position) { 5747 if (mViewTypeCount == 1) { 5748 return retrieveFromScrap(mCurrentScrap, position); 5749 } else { 5750 int whichScrap = mAdapter.getItemViewType(position); 5751 if (whichScrap >= 0 && whichScrap < mScrapViews.length) { 5752 return retrieveFromScrap(mScrapViews[whichScrap], position); 5753 } 5754 } 5755 return null; 5756 } 5757 5758 /** 5759 * Put a view into the ScapViews list. These views are unordered. 5760 * 5761 * @param scrap The view to add 5762 */ 5763 void addScrapView(View scrap, int position) { 5764 AbsListView.LayoutParams lp = (AbsListView.LayoutParams) scrap.getLayoutParams(); 5765 if (lp == null) { 5766 return; 5767 } 5768 5769 // Don't put header or footer views or views that should be ignored 5770 // into the scrap heap 5771 int viewType = lp.viewType; 5772 if (!shouldRecycleViewType(viewType)) { 5773 if (viewType != ITEM_VIEW_TYPE_HEADER_OR_FOOTER) { 5774 removeDetachedView(scrap, false); 5775 } 5776 return; 5777 } 5778 5779 lp.scrappedFromPosition = position; 5780 5781 if (mViewTypeCount == 1) { 5782 scrap.dispatchStartTemporaryDetach(); 5783 mCurrentScrap.add(scrap); 5784 } else { 5785 scrap.dispatchStartTemporaryDetach(); 5786 mScrapViews[viewType].add(scrap); 5787 } 5788 5789 if (mRecyclerListener != null) { 5790 mRecyclerListener.onMovedToScrapHeap(scrap); 5791 } 5792 } 5793 5794 /** 5795 * Move all views remaining in mActiveViews to mScrapViews. 5796 */ 5797 void scrapActiveViews() { 5798 final View[] activeViews = mActiveViews; 5799 final boolean hasListener = mRecyclerListener != null; 5800 final boolean multipleScraps = mViewTypeCount > 1; 5801 5802 ArrayList<View> scrapViews = mCurrentScrap; 5803 final int count = activeViews.length; 5804 for (int i = count - 1; i >= 0; i--) { 5805 final View victim = activeViews[i]; 5806 if (victim != null) { 5807 final AbsListView.LayoutParams lp 5808 = (AbsListView.LayoutParams) victim.getLayoutParams(); 5809 int whichScrap = lp.viewType; 5810 5811 activeViews[i] = null; 5812 5813 if (!shouldRecycleViewType(whichScrap)) { 5814 // Do not move views that should be ignored 5815 if (whichScrap != ITEM_VIEW_TYPE_HEADER_OR_FOOTER) { 5816 removeDetachedView(victim, false); 5817 } 5818 continue; 5819 } 5820 5821 if (multipleScraps) { 5822 scrapViews = mScrapViews[whichScrap]; 5823 } 5824 victim.dispatchStartTemporaryDetach(); 5825 lp.scrappedFromPosition = mFirstActivePosition + i; 5826 scrapViews.add(victim); 5827 5828 if (hasListener) { 5829 mRecyclerListener.onMovedToScrapHeap(victim); 5830 } 5831 5832 if (ViewDebug.TRACE_RECYCLER) { 5833 ViewDebug.trace(victim, 5834 ViewDebug.RecyclerTraceType.MOVE_FROM_ACTIVE_TO_SCRAP_HEAP, 5835 mFirstActivePosition + i, -1); 5836 } 5837 } 5838 } 5839 5840 pruneScrapViews(); 5841 } 5842 5843 /** 5844 * Makes sure that the size of mScrapViews does not exceed the size of mActiveViews. 5845 * (This can happen if an adapter does not recycle its views). 5846 */ 5847 private void pruneScrapViews() { 5848 final int maxViews = mActiveViews.length; 5849 final int viewTypeCount = mViewTypeCount; 5850 final ArrayList<View>[] scrapViews = mScrapViews; 5851 for (int i = 0; i < viewTypeCount; ++i) { 5852 final ArrayList<View> scrapPile = scrapViews[i]; 5853 int size = scrapPile.size(); 5854 final int extras = size - maxViews; 5855 size--; 5856 for (int j = 0; j < extras; j++) { 5857 removeDetachedView(scrapPile.remove(size--), false); 5858 } 5859 } 5860 } 5861 5862 /** 5863 * Puts all views in the scrap heap into the supplied list. 5864 */ 5865 void reclaimScrapViews(List<View> views) { 5866 if (mViewTypeCount == 1) { 5867 views.addAll(mCurrentScrap); 5868 } else { 5869 final int viewTypeCount = mViewTypeCount; 5870 final ArrayList<View>[] scrapViews = mScrapViews; 5871 for (int i = 0; i < viewTypeCount; ++i) { 5872 final ArrayList<View> scrapPile = scrapViews[i]; 5873 views.addAll(scrapPile); 5874 } 5875 } 5876 } 5877 5878 /** 5879 * Updates the cache color hint of all known views. 5880 * 5881 * @param color The new cache color hint. 5882 */ 5883 void setCacheColorHint(int color) { 5884 if (mViewTypeCount == 1) { 5885 final ArrayList<View> scrap = mCurrentScrap; 5886 final int scrapCount = scrap.size(); 5887 for (int i = 0; i < scrapCount; i++) { 5888 scrap.get(i).setDrawingCacheBackgroundColor(color); 5889 } 5890 } else { 5891 final int typeCount = mViewTypeCount; 5892 for (int i = 0; i < typeCount; i++) { 5893 final ArrayList<View> scrap = mScrapViews[i]; 5894 final int scrapCount = scrap.size(); 5895 for (int j = 0; j < scrapCount; j++) { 5896 scrap.get(j).setDrawingCacheBackgroundColor(color); 5897 } 5898 } 5899 } 5900 // Just in case this is called during a layout pass 5901 final View[] activeViews = mActiveViews; 5902 final int count = activeViews.length; 5903 for (int i = 0; i < count; ++i) { 5904 final View victim = activeViews[i]; 5905 if (victim != null) { 5906 victim.setDrawingCacheBackgroundColor(color); 5907 } 5908 } 5909 } 5910 } 5911 5912 static View retrieveFromScrap(ArrayList<View> scrapViews, int position) { 5913 int size = scrapViews.size(); 5914 if (size > 0) { 5915 // See if we still have a view for this position. 5916 for (int i=0; i<size; i++) { 5917 View view = scrapViews.get(i); 5918 if (((AbsListView.LayoutParams)view.getLayoutParams()) 5919 .scrappedFromPosition == position) { 5920 scrapViews.remove(i); 5921 return view; 5922 } 5923 } 5924 return scrapViews.remove(size - 1); 5925 } else { 5926 return null; 5927 } 5928 } 5929} 5930