ViewGroup.java revision e8585b1721b84798c4e7413939fd085f7a39bc0e
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.view; 18 19import android.animation.LayoutTransition; 20import android.content.Context; 21import android.content.res.Configuration; 22import android.content.res.TypedArray; 23import android.graphics.Bitmap; 24import android.graphics.Canvas; 25import android.graphics.Matrix; 26import android.graphics.Paint; 27import android.graphics.PointF; 28import android.graphics.Rect; 29import android.graphics.RectF; 30import android.graphics.Region; 31import android.os.Build; 32import android.os.Parcelable; 33import android.os.SystemClock; 34import android.util.AttributeSet; 35import android.util.Log; 36import android.util.SparseArray; 37import android.view.accessibility.AccessibilityEvent; 38import android.view.accessibility.AccessibilityNodeInfo; 39import android.view.animation.Animation; 40import android.view.animation.AnimationUtils; 41import android.view.animation.LayoutAnimationController; 42import android.view.animation.Transformation; 43 44import com.android.internal.R; 45import com.android.internal.util.Predicate; 46 47import java.util.ArrayList; 48import java.util.HashSet; 49 50/** 51 * <p> 52 * A <code>ViewGroup</code> is a special view that can contain other views 53 * (called children.) The view group is the base class for layouts and views 54 * containers. This class also defines the 55 * {@link android.view.ViewGroup.LayoutParams} class which serves as the base 56 * class for layouts parameters. 57 * </p> 58 * 59 * <p> 60 * Also see {@link LayoutParams} for layout attributes. 61 * </p> 62 * 63 * <div class="special reference"> 64 * <h3>Developer Guides</h3> 65 * <p>For more information about creating user interface layouts, read the 66 * <a href="{@docRoot}guide/topics/ui/declaring-layout.html">XML Layouts</a> developer 67 * guide.</p></div> 68 * 69 * @attr ref android.R.styleable#ViewGroup_clipChildren 70 * @attr ref android.R.styleable#ViewGroup_clipToPadding 71 * @attr ref android.R.styleable#ViewGroup_layoutAnimation 72 * @attr ref android.R.styleable#ViewGroup_animationCache 73 * @attr ref android.R.styleable#ViewGroup_persistentDrawingCache 74 * @attr ref android.R.styleable#ViewGroup_alwaysDrawnWithCache 75 * @attr ref android.R.styleable#ViewGroup_addStatesFromChildren 76 * @attr ref android.R.styleable#ViewGroup_descendantFocusability 77 * @attr ref android.R.styleable#ViewGroup_animateLayoutChanges 78 */ 79public abstract class ViewGroup extends View implements ViewParent, ViewManager { 80 private static final String TAG = "ViewGroup"; 81 82 private static final boolean DBG = false; 83 84 /** 85 * Views which have been hidden or removed which need to be animated on 86 * their way out. 87 * This field should be made private, so it is hidden from the SDK. 88 * {@hide} 89 */ 90 protected ArrayList<View> mDisappearingChildren; 91 92 /** 93 * Listener used to propagate events indicating when children are added 94 * and/or removed from a view group. 95 * This field should be made private, so it is hidden from the SDK. 96 * {@hide} 97 */ 98 protected OnHierarchyChangeListener mOnHierarchyChangeListener; 99 100 // The view contained within this ViewGroup that has or contains focus. 101 private View mFocused; 102 103 /** 104 * A Transformation used when drawing children, to 105 * apply on the child being drawn. 106 */ 107 final Transformation mChildTransformation = new Transformation(); 108 109 /** 110 * Used to track the current invalidation region. 111 */ 112 RectF mInvalidateRegion; 113 114 /** 115 * A Transformation used to calculate a correct 116 * invalidation area when the application is autoscaled. 117 */ 118 Transformation mInvalidationTransformation; 119 120 // View currently under an ongoing drag 121 private View mCurrentDragView; 122 123 // Metadata about the ongoing drag 124 private DragEvent mCurrentDrag; 125 private HashSet<View> mDragNotifiedChildren; 126 127 // Does this group have a child that can accept the current drag payload? 128 private boolean mChildAcceptsDrag; 129 130 // Used during drag dispatch 131 private final PointF mLocalPoint = new PointF(); 132 133 // Layout animation 134 private LayoutAnimationController mLayoutAnimationController; 135 private Animation.AnimationListener mAnimationListener; 136 137 // First touch target in the linked list of touch targets. 138 private TouchTarget mFirstTouchTarget; 139 140 // For debugging only. You can see these in hierarchyviewer. 141 @SuppressWarnings({"FieldCanBeLocal", "UnusedDeclaration"}) 142 @ViewDebug.ExportedProperty(category = "events") 143 private long mLastTouchDownTime; 144 @ViewDebug.ExportedProperty(category = "events") 145 private int mLastTouchDownIndex = -1; 146 @SuppressWarnings({"FieldCanBeLocal", "UnusedDeclaration"}) 147 @ViewDebug.ExportedProperty(category = "events") 148 private float mLastTouchDownX; 149 @SuppressWarnings({"FieldCanBeLocal", "UnusedDeclaration"}) 150 @ViewDebug.ExportedProperty(category = "events") 151 private float mLastTouchDownY; 152 153 // First hover target in the linked list of hover targets. 154 // The hover targets are children which have received ACTION_HOVER_ENTER. 155 // They might not have actually handled the hover event, but we will 156 // continue sending hover events to them as long as the pointer remains over 157 // their bounds and the view group does not intercept hover. 158 private HoverTarget mFirstHoverTarget; 159 160 // True if the view group itself received a hover event. 161 // It might not have actually handled the hover event. 162 private boolean mHoveredSelf; 163 164 /** 165 * Internal flags. 166 * 167 * This field should be made private, so it is hidden from the SDK. 168 * {@hide} 169 */ 170 protected int mGroupFlags; 171 172 /** 173 * NOTE: If you change the flags below make sure to reflect the changes 174 * the DisplayList class 175 */ 176 177 // When set, ViewGroup invalidates only the child's rectangle 178 // Set by default 179 static final int FLAG_CLIP_CHILDREN = 0x1; 180 181 // When set, ViewGroup excludes the padding area from the invalidate rectangle 182 // Set by default 183 private static final int FLAG_CLIP_TO_PADDING = 0x2; 184 185 // When set, dispatchDraw() will invoke invalidate(); this is set by drawChild() when 186 // a child needs to be invalidated and FLAG_OPTIMIZE_INVALIDATE is set 187 static final int FLAG_INVALIDATE_REQUIRED = 0x4; 188 189 // When set, dispatchDraw() will run the layout animation and unset the flag 190 private static final int FLAG_RUN_ANIMATION = 0x8; 191 192 // When set, there is either no layout animation on the ViewGroup or the layout 193 // animation is over 194 // Set by default 195 static final int FLAG_ANIMATION_DONE = 0x10; 196 197 // If set, this ViewGroup has padding; if unset there is no padding and we don't need 198 // to clip it, even if FLAG_CLIP_TO_PADDING is set 199 private static final int FLAG_PADDING_NOT_NULL = 0x20; 200 201 // When set, this ViewGroup caches its children in a Bitmap before starting a layout animation 202 // Set by default 203 private static final int FLAG_ANIMATION_CACHE = 0x40; 204 205 // When set, this ViewGroup converts calls to invalidate(Rect) to invalidate() during a 206 // layout animation; this avoid clobbering the hierarchy 207 // Automatically set when the layout animation starts, depending on the animation's 208 // characteristics 209 static final int FLAG_OPTIMIZE_INVALIDATE = 0x80; 210 211 // When set, the next call to drawChild() will clear mChildTransformation's matrix 212 static final int FLAG_CLEAR_TRANSFORMATION = 0x100; 213 214 // When set, this ViewGroup invokes mAnimationListener.onAnimationEnd() and removes 215 // the children's Bitmap caches if necessary 216 // This flag is set when the layout animation is over (after FLAG_ANIMATION_DONE is set) 217 private static final int FLAG_NOTIFY_ANIMATION_LISTENER = 0x200; 218 219 /** 220 * When set, the drawing method will call {@link #getChildDrawingOrder(int, int)} 221 * to get the index of the child to draw for that iteration. 222 * 223 * @hide 224 */ 225 protected static final int FLAG_USE_CHILD_DRAWING_ORDER = 0x400; 226 227 /** 228 * When set, this ViewGroup supports static transformations on children; this causes 229 * {@link #getChildStaticTransformation(View, android.view.animation.Transformation)} to be 230 * invoked when a child is drawn. 231 * 232 * Any subclass overriding 233 * {@link #getChildStaticTransformation(View, android.view.animation.Transformation)} should 234 * set this flags in {@link #mGroupFlags}. 235 * 236 * {@hide} 237 */ 238 protected static final int FLAG_SUPPORT_STATIC_TRANSFORMATIONS = 0x800; 239 240 // When the previous drawChild() invocation used an alpha value that was lower than 241 // 1.0 and set it in mCachePaint 242 static final int FLAG_ALPHA_LOWER_THAN_ONE = 0x1000; 243 244 /** 245 * When set, this ViewGroup's drawable states also include those 246 * of its children. 247 */ 248 private static final int FLAG_ADD_STATES_FROM_CHILDREN = 0x2000; 249 250 /** 251 * When set, this ViewGroup tries to always draw its children using their drawing cache. 252 */ 253 static final int FLAG_ALWAYS_DRAWN_WITH_CACHE = 0x4000; 254 255 /** 256 * When set, and if FLAG_ALWAYS_DRAWN_WITH_CACHE is not set, this ViewGroup will try to 257 * draw its children with their drawing cache. 258 */ 259 static final int FLAG_CHILDREN_DRAWN_WITH_CACHE = 0x8000; 260 261 /** 262 * When set, this group will go through its list of children to notify them of 263 * any drawable state change. 264 */ 265 private static final int FLAG_NOTIFY_CHILDREN_ON_DRAWABLE_STATE_CHANGE = 0x10000; 266 267 private static final int FLAG_MASK_FOCUSABILITY = 0x60000; 268 269 /** 270 * This view will get focus before any of its descendants. 271 */ 272 public static final int FOCUS_BEFORE_DESCENDANTS = 0x20000; 273 274 /** 275 * This view will get focus only if none of its descendants want it. 276 */ 277 public static final int FOCUS_AFTER_DESCENDANTS = 0x40000; 278 279 /** 280 * This view will block any of its descendants from getting focus, even 281 * if they are focusable. 282 */ 283 public static final int FOCUS_BLOCK_DESCENDANTS = 0x60000; 284 285 /** 286 * Used to map between enum in attrubutes and flag values. 287 */ 288 private static final int[] DESCENDANT_FOCUSABILITY_FLAGS = 289 {FOCUS_BEFORE_DESCENDANTS, FOCUS_AFTER_DESCENDANTS, 290 FOCUS_BLOCK_DESCENDANTS}; 291 292 /** 293 * When set, this ViewGroup should not intercept touch events. 294 * {@hide} 295 */ 296 protected static final int FLAG_DISALLOW_INTERCEPT = 0x80000; 297 298 /** 299 * When set, this ViewGroup will split MotionEvents to multiple child Views when appropriate. 300 */ 301 private static final int FLAG_SPLIT_MOTION_EVENTS = 0x200000; 302 303 /** 304 * When set, this ViewGroup will not dispatch onAttachedToWindow calls 305 * to children when adding new views. This is used to prevent multiple 306 * onAttached calls when a ViewGroup adds children in its own onAttached method. 307 */ 308 private static final int FLAG_PREVENT_DISPATCH_ATTACHED_TO_WINDOW = 0x400000; 309 310 /** 311 * Indicates which types of drawing caches are to be kept in memory. 312 * This field should be made private, so it is hidden from the SDK. 313 * {@hide} 314 */ 315 protected int mPersistentDrawingCache; 316 317 /** 318 * Used to indicate that no drawing cache should be kept in memory. 319 */ 320 public static final int PERSISTENT_NO_CACHE = 0x0; 321 322 /** 323 * Used to indicate that the animation drawing cache should be kept in memory. 324 */ 325 public static final int PERSISTENT_ANIMATION_CACHE = 0x1; 326 327 /** 328 * Used to indicate that the scrolling drawing cache should be kept in memory. 329 */ 330 public static final int PERSISTENT_SCROLLING_CACHE = 0x2; 331 332 /** 333 * Used to indicate that all drawing caches should be kept in memory. 334 */ 335 public static final int PERSISTENT_ALL_CACHES = 0x3; 336 337 /** 338 * We clip to padding when FLAG_CLIP_TO_PADDING and FLAG_PADDING_NOT_NULL 339 * are set at the same time. 340 */ 341 protected static final int CLIP_TO_PADDING_MASK = FLAG_CLIP_TO_PADDING | FLAG_PADDING_NOT_NULL; 342 343 // Index of the child's left position in the mLocation array 344 private static final int CHILD_LEFT_INDEX = 0; 345 // Index of the child's top position in the mLocation array 346 private static final int CHILD_TOP_INDEX = 1; 347 348 // Child views of this ViewGroup 349 private View[] mChildren; 350 // Number of valid children in the mChildren array, the rest should be null or not 351 // considered as children 352 353 private boolean mLayoutSuppressed = false; 354 355 private int mChildrenCount; 356 357 private static final int ARRAY_INITIAL_CAPACITY = 12; 358 private static final int ARRAY_CAPACITY_INCREMENT = 12; 359 360 // Used to draw cached views 361 Paint mCachePaint; 362 363 // Used to animate add/remove changes in layout 364 private LayoutTransition mTransition; 365 366 // The set of views that are currently being transitioned. This list is used to track views 367 // being removed that should not actually be removed from the parent yet because they are 368 // being animated. 369 private ArrayList<View> mTransitioningViews; 370 371 // List of children changing visibility. This is used to potentially keep rendering 372 // views during a transition when they otherwise would have become gone/invisible 373 private ArrayList<View> mVisibilityChangingChildren; 374 375 // Indicates whether this container will use its children layers to draw 376 @ViewDebug.ExportedProperty(category = "drawing") 377 boolean mDrawLayers = true; 378 379 // Indicates how many of this container's child subtrees contain transient state 380 @ViewDebug.ExportedProperty(category = "layout") 381 private int mChildCountWithTransientState = 0; 382 383 public ViewGroup(Context context) { 384 super(context); 385 initViewGroup(); 386 } 387 388 public ViewGroup(Context context, AttributeSet attrs) { 389 super(context, attrs); 390 initViewGroup(); 391 initFromAttributes(context, attrs); 392 } 393 394 public ViewGroup(Context context, AttributeSet attrs, int defStyle) { 395 super(context, attrs, defStyle); 396 initViewGroup(); 397 initFromAttributes(context, attrs); 398 } 399 400 private void initViewGroup() { 401 // ViewGroup doesn't draw by default 402 setFlags(WILL_NOT_DRAW, DRAW_MASK); 403 mGroupFlags |= FLAG_CLIP_CHILDREN; 404 mGroupFlags |= FLAG_CLIP_TO_PADDING; 405 mGroupFlags |= FLAG_ANIMATION_DONE; 406 mGroupFlags |= FLAG_ANIMATION_CACHE; 407 mGroupFlags |= FLAG_ALWAYS_DRAWN_WITH_CACHE; 408 409 if (mContext.getApplicationInfo().targetSdkVersion >= Build.VERSION_CODES.HONEYCOMB) { 410 mGroupFlags |= FLAG_SPLIT_MOTION_EVENTS; 411 } 412 413 setDescendantFocusability(FOCUS_BEFORE_DESCENDANTS); 414 415 mChildren = new View[ARRAY_INITIAL_CAPACITY]; 416 mChildrenCount = 0; 417 418 mPersistentDrawingCache = PERSISTENT_SCROLLING_CACHE; 419 } 420 421 private void initFromAttributes(Context context, AttributeSet attrs) { 422 TypedArray a = context.obtainStyledAttributes(attrs, 423 R.styleable.ViewGroup); 424 425 final int N = a.getIndexCount(); 426 for (int i = 0; i < N; i++) { 427 int attr = a.getIndex(i); 428 switch (attr) { 429 case R.styleable.ViewGroup_clipChildren: 430 setClipChildren(a.getBoolean(attr, true)); 431 break; 432 case R.styleable.ViewGroup_clipToPadding: 433 setClipToPadding(a.getBoolean(attr, true)); 434 break; 435 case R.styleable.ViewGroup_animationCache: 436 setAnimationCacheEnabled(a.getBoolean(attr, true)); 437 break; 438 case R.styleable.ViewGroup_persistentDrawingCache: 439 setPersistentDrawingCache(a.getInt(attr, PERSISTENT_SCROLLING_CACHE)); 440 break; 441 case R.styleable.ViewGroup_addStatesFromChildren: 442 setAddStatesFromChildren(a.getBoolean(attr, false)); 443 break; 444 case R.styleable.ViewGroup_alwaysDrawnWithCache: 445 setAlwaysDrawnWithCacheEnabled(a.getBoolean(attr, true)); 446 break; 447 case R.styleable.ViewGroup_layoutAnimation: 448 int id = a.getResourceId(attr, -1); 449 if (id > 0) { 450 setLayoutAnimation(AnimationUtils.loadLayoutAnimation(mContext, id)); 451 } 452 break; 453 case R.styleable.ViewGroup_descendantFocusability: 454 setDescendantFocusability(DESCENDANT_FOCUSABILITY_FLAGS[a.getInt(attr, 0)]); 455 break; 456 case R.styleable.ViewGroup_splitMotionEvents: 457 setMotionEventSplittingEnabled(a.getBoolean(attr, false)); 458 break; 459 case R.styleable.ViewGroup_animateLayoutChanges: 460 boolean animateLayoutChanges = a.getBoolean(attr, false); 461 if (animateLayoutChanges) { 462 setLayoutTransition(new LayoutTransition()); 463 } 464 break; 465 } 466 } 467 468 a.recycle(); 469 } 470 471 /** 472 * Gets the descendant focusability of this view group. The descendant 473 * focusability defines the relationship between this view group and its 474 * descendants when looking for a view to take focus in 475 * {@link #requestFocus(int, android.graphics.Rect)}. 476 * 477 * @return one of {@link #FOCUS_BEFORE_DESCENDANTS}, {@link #FOCUS_AFTER_DESCENDANTS}, 478 * {@link #FOCUS_BLOCK_DESCENDANTS}. 479 */ 480 @ViewDebug.ExportedProperty(category = "focus", mapping = { 481 @ViewDebug.IntToString(from = FOCUS_BEFORE_DESCENDANTS, to = "FOCUS_BEFORE_DESCENDANTS"), 482 @ViewDebug.IntToString(from = FOCUS_AFTER_DESCENDANTS, to = "FOCUS_AFTER_DESCENDANTS"), 483 @ViewDebug.IntToString(from = FOCUS_BLOCK_DESCENDANTS, to = "FOCUS_BLOCK_DESCENDANTS") 484 }) 485 public int getDescendantFocusability() { 486 return mGroupFlags & FLAG_MASK_FOCUSABILITY; 487 } 488 489 /** 490 * Set the descendant focusability of this view group. This defines the relationship 491 * between this view group and its descendants when looking for a view to 492 * take focus in {@link #requestFocus(int, android.graphics.Rect)}. 493 * 494 * @param focusability one of {@link #FOCUS_BEFORE_DESCENDANTS}, {@link #FOCUS_AFTER_DESCENDANTS}, 495 * {@link #FOCUS_BLOCK_DESCENDANTS}. 496 */ 497 public void setDescendantFocusability(int focusability) { 498 switch (focusability) { 499 case FOCUS_BEFORE_DESCENDANTS: 500 case FOCUS_AFTER_DESCENDANTS: 501 case FOCUS_BLOCK_DESCENDANTS: 502 break; 503 default: 504 throw new IllegalArgumentException("must be one of FOCUS_BEFORE_DESCENDANTS, " 505 + "FOCUS_AFTER_DESCENDANTS, FOCUS_BLOCK_DESCENDANTS"); 506 } 507 mGroupFlags &= ~FLAG_MASK_FOCUSABILITY; 508 mGroupFlags |= (focusability & FLAG_MASK_FOCUSABILITY); 509 } 510 511 /** 512 * {@inheritDoc} 513 */ 514 @Override 515 void handleFocusGainInternal(int direction, Rect previouslyFocusedRect) { 516 if (mFocused != null) { 517 mFocused.unFocus(); 518 mFocused = null; 519 } 520 super.handleFocusGainInternal(direction, previouslyFocusedRect); 521 } 522 523 /** 524 * {@inheritDoc} 525 */ 526 public void requestChildFocus(View child, View focused) { 527 if (DBG) { 528 System.out.println(this + " requestChildFocus()"); 529 } 530 if (getDescendantFocusability() == FOCUS_BLOCK_DESCENDANTS) { 531 return; 532 } 533 534 // Unfocus us, if necessary 535 super.unFocus(); 536 537 // We had a previous notion of who had focus. Clear it. 538 if (mFocused != child) { 539 if (mFocused != null) { 540 mFocused.unFocus(); 541 } 542 543 mFocused = child; 544 } 545 if (mParent != null) { 546 mParent.requestChildFocus(this, focused); 547 } 548 } 549 550 /** 551 * {@inheritDoc} 552 */ 553 public void focusableViewAvailable(View v) { 554 if (mParent != null 555 // shortcut: don't report a new focusable view if we block our descendants from 556 // getting focus 557 && (getDescendantFocusability() != FOCUS_BLOCK_DESCENDANTS) 558 // shortcut: don't report a new focusable view if we already are focused 559 // (and we don't prefer our descendants) 560 // 561 // note: knowing that mFocused is non-null is not a good enough reason 562 // to break the traversal since in that case we'd actually have to find 563 // the focused view and make sure it wasn't FOCUS_AFTER_DESCENDANTS and 564 // an ancestor of v; this will get checked for at ViewAncestor 565 && !(isFocused() && getDescendantFocusability() != FOCUS_AFTER_DESCENDANTS)) { 566 mParent.focusableViewAvailable(v); 567 } 568 } 569 570 /** 571 * {@inheritDoc} 572 */ 573 public boolean showContextMenuForChild(View originalView) { 574 return mParent != null && mParent.showContextMenuForChild(originalView); 575 } 576 577 /** 578 * {@inheritDoc} 579 */ 580 public ActionMode startActionModeForChild(View originalView, ActionMode.Callback callback) { 581 return mParent != null ? mParent.startActionModeForChild(originalView, callback) : null; 582 } 583 584 /** 585 * Find the nearest view in the specified direction that wants to take 586 * focus. 587 * 588 * @param focused The view that currently has focus 589 * @param direction One of FOCUS_UP, FOCUS_DOWN, FOCUS_LEFT, and 590 * FOCUS_RIGHT, or 0 for not applicable. 591 */ 592 public View focusSearch(View focused, int direction) { 593 if (isRootNamespace()) { 594 // root namespace means we should consider ourselves the top of the 595 // tree for focus searching; otherwise we could be focus searching 596 // into other tabs. see LocalActivityManager and TabHost for more info 597 return FocusFinder.getInstance().findNextFocus(this, focused, direction); 598 } else if (mParent != null) { 599 return mParent.focusSearch(focused, direction); 600 } 601 return null; 602 } 603 604 /** 605 * {@inheritDoc} 606 */ 607 public boolean requestChildRectangleOnScreen(View child, Rect rectangle, boolean immediate) { 608 return false; 609 } 610 611 /** 612 * {@inheritDoc} 613 */ 614 public boolean requestSendAccessibilityEvent(View child, AccessibilityEvent event) { 615 ViewParent parent = getParent(); 616 if (parent == null) { 617 return false; 618 } 619 final boolean propagate = onRequestSendAccessibilityEvent(child, event); 620 //noinspection SimplifiableIfStatement 621 if (!propagate) { 622 return false; 623 } 624 return parent.requestSendAccessibilityEvent(this, event); 625 } 626 627 /** 628 * Called when a child has requested sending an {@link AccessibilityEvent} and 629 * gives an opportunity to its parent to augment the event. 630 * <p> 631 * If an {@link android.view.View.AccessibilityDelegate} has been specified via calling 632 * {@link android.view.View#setAccessibilityDelegate(android.view.View.AccessibilityDelegate)} its 633 * {@link android.view.View.AccessibilityDelegate#onRequestSendAccessibilityEvent(ViewGroup, View, AccessibilityEvent)} 634 * is responsible for handling this call. 635 * </p> 636 * 637 * @param child The child which requests sending the event. 638 * @param event The event to be sent. 639 * @return True if the event should be sent. 640 * 641 * @see #requestSendAccessibilityEvent(View, AccessibilityEvent) 642 */ 643 public boolean onRequestSendAccessibilityEvent(View child, AccessibilityEvent event) { 644 if (mAccessibilityDelegate != null) { 645 return mAccessibilityDelegate.onRequestSendAccessibilityEvent(this, child, event); 646 } else { 647 return onRequestSendAccessibilityEventInternal(child, event); 648 } 649 } 650 651 /** 652 * @see #onRequestSendAccessibilityEvent(View, AccessibilityEvent) 653 * 654 * Note: Called from the default {@link View.AccessibilityDelegate}. 655 */ 656 boolean onRequestSendAccessibilityEventInternal(View child, AccessibilityEvent event) { 657 return true; 658 } 659 660 /** 661 * Called when a child view has changed whether or not it is tracking transient state. 662 * 663 * @hide 664 */ 665 public void childHasTransientStateChanged(View child, boolean childHasTransientState) { 666 final boolean oldHasTransientState = hasTransientState(); 667 if (childHasTransientState) { 668 mChildCountWithTransientState++; 669 } else { 670 mChildCountWithTransientState--; 671 } 672 673 final boolean newHasTransientState = hasTransientState(); 674 if (mParent != null && oldHasTransientState != newHasTransientState) { 675 try { 676 mParent.childHasTransientStateChanged(this, newHasTransientState); 677 } catch (AbstractMethodError e) { 678 Log.e(TAG, mParent.getClass().getSimpleName() + 679 " does not fully implement ViewParent", e); 680 } 681 } 682 } 683 684 /** 685 * @hide 686 */ 687 @Override 688 public boolean hasTransientState() { 689 return mChildCountWithTransientState > 0 || super.hasTransientState(); 690 } 691 692 /** 693 * {@inheritDoc} 694 */ 695 @Override 696 public boolean dispatchUnhandledMove(View focused, int direction) { 697 return mFocused != null && 698 mFocused.dispatchUnhandledMove(focused, direction); 699 } 700 701 /** 702 * {@inheritDoc} 703 */ 704 public void clearChildFocus(View child) { 705 if (DBG) { 706 System.out.println(this + " clearChildFocus()"); 707 } 708 709 mFocused = null; 710 if (mParent != null) { 711 mParent.clearChildFocus(this); 712 } 713 } 714 715 /** 716 * {@inheritDoc} 717 */ 718 @Override 719 public void clearFocus() { 720 if (DBG) { 721 System.out.println(this + " clearFocus()"); 722 } 723 if (mFocused == null) { 724 super.clearFocus(); 725 } else { 726 mFocused.clearFocus(); 727 mFocused = null; 728 } 729 } 730 731 /** 732 * {@inheritDoc} 733 */ 734 @Override 735 void unFocus() { 736 if (DBG) { 737 System.out.println(this + " unFocus()"); 738 } 739 if (mFocused == null) { 740 super.unFocus(); 741 } else { 742 mFocused.unFocus(); 743 mFocused = null; 744 } 745 } 746 747 /** 748 * Returns the focused child of this view, if any. The child may have focus 749 * or contain focus. 750 * 751 * @return the focused child or null. 752 */ 753 public View getFocusedChild() { 754 return mFocused; 755 } 756 757 /** 758 * Returns true if this view has or contains focus 759 * 760 * @return true if this view has or contains focus 761 */ 762 @Override 763 public boolean hasFocus() { 764 return (mPrivateFlags & FOCUSED) != 0 || mFocused != null; 765 } 766 767 /* 768 * (non-Javadoc) 769 * 770 * @see android.view.View#findFocus() 771 */ 772 @Override 773 public View findFocus() { 774 if (DBG) { 775 System.out.println("Find focus in " + this + ": flags=" 776 + isFocused() + ", child=" + mFocused); 777 } 778 779 if (isFocused()) { 780 return this; 781 } 782 783 if (mFocused != null) { 784 return mFocused.findFocus(); 785 } 786 return null; 787 } 788 789 /** 790 * {@inheritDoc} 791 */ 792 @Override 793 public boolean hasFocusable() { 794 if ((mViewFlags & VISIBILITY_MASK) != VISIBLE) { 795 return false; 796 } 797 798 if (isFocusable()) { 799 return true; 800 } 801 802 final int descendantFocusability = getDescendantFocusability(); 803 if (descendantFocusability != FOCUS_BLOCK_DESCENDANTS) { 804 final int count = mChildrenCount; 805 final View[] children = mChildren; 806 807 for (int i = 0; i < count; i++) { 808 final View child = children[i]; 809 if (child.hasFocusable()) { 810 return true; 811 } 812 } 813 } 814 815 return false; 816 } 817 818 /** 819 * {@inheritDoc} 820 */ 821 @Override 822 public void addFocusables(ArrayList<View> views, int direction) { 823 addFocusables(views, direction, FOCUSABLES_TOUCH_MODE); 824 } 825 826 /** 827 * {@inheritDoc} 828 */ 829 @Override 830 public void addFocusables(ArrayList<View> views, int direction, int focusableMode) { 831 final int focusableCount = views.size(); 832 833 final int descendantFocusability = getDescendantFocusability(); 834 835 if (descendantFocusability != FOCUS_BLOCK_DESCENDANTS) { 836 final int count = mChildrenCount; 837 final View[] children = mChildren; 838 839 for (int i = 0; i < count; i++) { 840 final View child = children[i]; 841 if ((child.mViewFlags & VISIBILITY_MASK) == VISIBLE) { 842 child.addFocusables(views, direction, focusableMode); 843 } 844 } 845 } 846 847 // we add ourselves (if focusable) in all cases except for when we are 848 // FOCUS_AFTER_DESCENDANTS and there are some descendants focusable. this is 849 // to avoid the focus search finding layouts when a more precise search 850 // among the focusable children would be more interesting. 851 if ( 852 descendantFocusability != FOCUS_AFTER_DESCENDANTS || 853 // No focusable descendants 854 (focusableCount == views.size())) { 855 super.addFocusables(views, direction, focusableMode); 856 } 857 } 858 859 @Override 860 public void findViewsWithText(ArrayList<View> outViews, CharSequence text, int flags) { 861 super.findViewsWithText(outViews, text, flags); 862 final int childrenCount = mChildrenCount; 863 final View[] children = mChildren; 864 for (int i = 0; i < childrenCount; i++) { 865 View child = children[i]; 866 if ((child.mViewFlags & VISIBILITY_MASK) == VISIBLE 867 && (child.mPrivateFlags & IS_ROOT_NAMESPACE) == 0) { 868 child.findViewsWithText(outViews, text, flags); 869 } 870 } 871 } 872 873 @Override 874 View findViewByAccessibilityIdTraversal(int accessibilityId) { 875 View foundView = super.findViewByAccessibilityIdTraversal(accessibilityId); 876 if (foundView != null) { 877 return foundView; 878 } 879 final int childrenCount = mChildrenCount; 880 final View[] children = mChildren; 881 for (int i = 0; i < childrenCount; i++) { 882 View child = children[i]; 883 foundView = child.findViewByAccessibilityIdTraversal(accessibilityId); 884 if (foundView != null) { 885 return foundView; 886 } 887 } 888 return null; 889 } 890 891 /** 892 * {@inheritDoc} 893 */ 894 @Override 895 public void dispatchWindowFocusChanged(boolean hasFocus) { 896 super.dispatchWindowFocusChanged(hasFocus); 897 final int count = mChildrenCount; 898 final View[] children = mChildren; 899 for (int i = 0; i < count; i++) { 900 children[i].dispatchWindowFocusChanged(hasFocus); 901 } 902 } 903 904 /** 905 * {@inheritDoc} 906 */ 907 @Override 908 public void addTouchables(ArrayList<View> views) { 909 super.addTouchables(views); 910 911 final int count = mChildrenCount; 912 final View[] children = mChildren; 913 914 for (int i = 0; i < count; i++) { 915 final View child = children[i]; 916 if ((child.mViewFlags & VISIBILITY_MASK) == VISIBLE) { 917 child.addTouchables(views); 918 } 919 } 920 } 921 922 /** 923 * {@inheritDoc} 924 */ 925 @Override 926 public void dispatchDisplayHint(int hint) { 927 super.dispatchDisplayHint(hint); 928 final int count = mChildrenCount; 929 final View[] children = mChildren; 930 for (int i = 0; i < count; i++) { 931 children[i].dispatchDisplayHint(hint); 932 } 933 } 934 935 /** 936 * Called when a view's visibility has changed. Notify the parent to take any appropriate 937 * action. 938 * 939 * @param child The view whose visibility has changed 940 * @param oldVisibility The previous visibility value (GONE, INVISIBLE, or VISIBLE). 941 * @param newVisibility The new visibility value (GONE, INVISIBLE, or VISIBLE). 942 * @hide 943 */ 944 protected void onChildVisibilityChanged(View child, int oldVisibility, int newVisibility) { 945 if (mTransition != null) { 946 if (newVisibility == VISIBLE) { 947 mTransition.showChild(this, child, oldVisibility); 948 } else { 949 mTransition.hideChild(this, child, newVisibility); 950 // Only track this on disappearing views - appearing views are already visible 951 // and don't need special handling during drawChild() 952 if (mVisibilityChangingChildren == null) { 953 mVisibilityChangingChildren = new ArrayList<View>(); 954 } 955 mVisibilityChangingChildren.add(child); 956 if (mTransitioningViews != null && mTransitioningViews.contains(child)) { 957 addDisappearingView(child); 958 } 959 } 960 } 961 962 // in all cases, for drags 963 if (mCurrentDrag != null) { 964 if (newVisibility == VISIBLE) { 965 notifyChildOfDrag(child); 966 } 967 } 968 } 969 970 /** 971 * {@inheritDoc} 972 */ 973 @Override 974 protected void dispatchVisibilityChanged(View changedView, int visibility) { 975 super.dispatchVisibilityChanged(changedView, visibility); 976 final int count = mChildrenCount; 977 final View[] children = mChildren; 978 for (int i = 0; i < count; i++) { 979 children[i].dispatchVisibilityChanged(changedView, visibility); 980 } 981 } 982 983 /** 984 * {@inheritDoc} 985 */ 986 @Override 987 public void dispatchWindowVisibilityChanged(int visibility) { 988 super.dispatchWindowVisibilityChanged(visibility); 989 final int count = mChildrenCount; 990 final View[] children = mChildren; 991 for (int i = 0; i < count; i++) { 992 children[i].dispatchWindowVisibilityChanged(visibility); 993 } 994 } 995 996 /** 997 * {@inheritDoc} 998 */ 999 @Override 1000 public void dispatchConfigurationChanged(Configuration newConfig) { 1001 super.dispatchConfigurationChanged(newConfig); 1002 final int count = mChildrenCount; 1003 final View[] children = mChildren; 1004 for (int i = 0; i < count; i++) { 1005 children[i].dispatchConfigurationChanged(newConfig); 1006 } 1007 } 1008 1009 /** 1010 * {@inheritDoc} 1011 */ 1012 public void recomputeViewAttributes(View child) { 1013 if (mAttachInfo != null && !mAttachInfo.mRecomputeGlobalAttributes) { 1014 ViewParent parent = mParent; 1015 if (parent != null) parent.recomputeViewAttributes(this); 1016 } 1017 } 1018 1019 @Override 1020 void dispatchCollectViewAttributes(int visibility) { 1021 visibility |= mViewFlags&VISIBILITY_MASK; 1022 super.dispatchCollectViewAttributes(visibility); 1023 final int count = mChildrenCount; 1024 final View[] children = mChildren; 1025 for (int i = 0; i < count; i++) { 1026 children[i].dispatchCollectViewAttributes(visibility); 1027 } 1028 } 1029 1030 /** 1031 * {@inheritDoc} 1032 */ 1033 public void bringChildToFront(View child) { 1034 int index = indexOfChild(child); 1035 if (index >= 0) { 1036 removeFromArray(index); 1037 addInArray(child, mChildrenCount); 1038 child.mParent = this; 1039 } 1040 } 1041 1042 /** 1043 * {@inheritDoc} 1044 * 1045 * !!! TODO: write real docs 1046 */ 1047 @Override 1048 public boolean dispatchDragEvent(DragEvent event) { 1049 boolean retval = false; 1050 final float tx = event.mX; 1051 final float ty = event.mY; 1052 1053 ViewRootImpl root = getViewRootImpl(); 1054 1055 // Dispatch down the view hierarchy 1056 switch (event.mAction) { 1057 case DragEvent.ACTION_DRAG_STARTED: { 1058 // clear state to recalculate which views we drag over 1059 mCurrentDragView = null; 1060 1061 // Set up our tracking of drag-started notifications 1062 mCurrentDrag = DragEvent.obtain(event); 1063 if (mDragNotifiedChildren == null) { 1064 mDragNotifiedChildren = new HashSet<View>(); 1065 } else { 1066 mDragNotifiedChildren.clear(); 1067 } 1068 1069 // Now dispatch down to our children, caching the responses 1070 mChildAcceptsDrag = false; 1071 final int count = mChildrenCount; 1072 final View[] children = mChildren; 1073 for (int i = 0; i < count; i++) { 1074 final View child = children[i]; 1075 child.mPrivateFlags2 &= ~View.DRAG_MASK; 1076 if (child.getVisibility() == VISIBLE) { 1077 final boolean handled = notifyChildOfDrag(children[i]); 1078 if (handled) { 1079 mChildAcceptsDrag = true; 1080 } 1081 } 1082 } 1083 1084 // Return HANDLED if one of our children can accept the drag 1085 if (mChildAcceptsDrag) { 1086 retval = true; 1087 } 1088 } break; 1089 1090 case DragEvent.ACTION_DRAG_ENDED: { 1091 // Release the bookkeeping now that the drag lifecycle has ended 1092 if (mDragNotifiedChildren != null) { 1093 for (View child : mDragNotifiedChildren) { 1094 // If a child was notified about an ongoing drag, it's told that it's over 1095 child.dispatchDragEvent(event); 1096 child.mPrivateFlags2 &= ~View.DRAG_MASK; 1097 child.refreshDrawableState(); 1098 } 1099 1100 mDragNotifiedChildren.clear(); 1101 mCurrentDrag.recycle(); 1102 mCurrentDrag = null; 1103 } 1104 1105 // We consider drag-ended to have been handled if one of our children 1106 // had offered to handle the drag. 1107 if (mChildAcceptsDrag) { 1108 retval = true; 1109 } 1110 } break; 1111 1112 case DragEvent.ACTION_DRAG_LOCATION: { 1113 // Find the [possibly new] drag target 1114 final View target = findFrontmostDroppableChildAt(event.mX, event.mY, mLocalPoint); 1115 1116 // If we've changed apparent drag target, tell the view root which view 1117 // we're over now [for purposes of the eventual drag-recipient-changed 1118 // notifications to the framework] and tell the new target that the drag 1119 // has entered its bounds. The root will see setDragFocus() calls all 1120 // the way down to the final leaf view that is handling the LOCATION event 1121 // before reporting the new potential recipient to the framework. 1122 if (mCurrentDragView != target) { 1123 root.setDragFocus(target); 1124 1125 final int action = event.mAction; 1126 // If we've dragged off of a child view, send it the EXITED message 1127 if (mCurrentDragView != null) { 1128 final View view = mCurrentDragView; 1129 event.mAction = DragEvent.ACTION_DRAG_EXITED; 1130 view.dispatchDragEvent(event); 1131 view.mPrivateFlags2 &= ~View.DRAG_HOVERED; 1132 view.refreshDrawableState(); 1133 } 1134 mCurrentDragView = target; 1135 1136 // If we've dragged over a new child view, send it the ENTERED message 1137 if (target != null) { 1138 event.mAction = DragEvent.ACTION_DRAG_ENTERED; 1139 target.dispatchDragEvent(event); 1140 target.mPrivateFlags2 |= View.DRAG_HOVERED; 1141 target.refreshDrawableState(); 1142 } 1143 event.mAction = action; // restore the event's original state 1144 } 1145 1146 // Dispatch the actual drag location notice, localized into its coordinates 1147 if (target != null) { 1148 event.mX = mLocalPoint.x; 1149 event.mY = mLocalPoint.y; 1150 1151 retval = target.dispatchDragEvent(event); 1152 1153 event.mX = tx; 1154 event.mY = ty; 1155 } 1156 } break; 1157 1158 /* Entered / exited dispatch 1159 * 1160 * DRAG_ENTERED is not dispatched downwards from ViewGroup. The reason for this is 1161 * that we're about to get the corresponding LOCATION event, which we will use to 1162 * determine which of our children is the new target; at that point we will 1163 * push a DRAG_ENTERED down to the new target child [which may itself be a ViewGroup]. 1164 * 1165 * DRAG_EXITED *is* dispatched all the way down immediately: once we know the 1166 * drag has left this ViewGroup, we know by definition that every contained subview 1167 * is also no longer under the drag point. 1168 */ 1169 1170 case DragEvent.ACTION_DRAG_EXITED: { 1171 if (mCurrentDragView != null) { 1172 final View view = mCurrentDragView; 1173 view.dispatchDragEvent(event); 1174 view.mPrivateFlags2 &= ~View.DRAG_HOVERED; 1175 view.refreshDrawableState(); 1176 1177 mCurrentDragView = null; 1178 } 1179 } break; 1180 1181 case DragEvent.ACTION_DROP: { 1182 if (ViewDebug.DEBUG_DRAG) Log.d(View.VIEW_LOG_TAG, "Drop event: " + event); 1183 View target = findFrontmostDroppableChildAt(event.mX, event.mY, mLocalPoint); 1184 if (target != null) { 1185 if (ViewDebug.DEBUG_DRAG) Log.d(View.VIEW_LOG_TAG, " dispatch drop to " + target); 1186 event.mX = mLocalPoint.x; 1187 event.mY = mLocalPoint.y; 1188 retval = target.dispatchDragEvent(event); 1189 event.mX = tx; 1190 event.mY = ty; 1191 } else { 1192 if (ViewDebug.DEBUG_DRAG) { 1193 Log.d(View.VIEW_LOG_TAG, " not dropped on an accepting view"); 1194 } 1195 } 1196 } break; 1197 } 1198 1199 // If none of our children could handle the event, try here 1200 if (!retval) { 1201 // Call up to the View implementation that dispatches to installed listeners 1202 retval = super.dispatchDragEvent(event); 1203 } 1204 return retval; 1205 } 1206 1207 // Find the frontmost child view that lies under the given point, and calculate 1208 // the position within its own local coordinate system. 1209 View findFrontmostDroppableChildAt(float x, float y, PointF outLocalPoint) { 1210 final int count = mChildrenCount; 1211 final View[] children = mChildren; 1212 for (int i = count - 1; i >= 0; i--) { 1213 final View child = children[i]; 1214 if (!child.canAcceptDrag()) { 1215 continue; 1216 } 1217 1218 if (isTransformedTouchPointInView(x, y, child, outLocalPoint)) { 1219 return child; 1220 } 1221 } 1222 return null; 1223 } 1224 1225 boolean notifyChildOfDrag(View child) { 1226 if (ViewDebug.DEBUG_DRAG) { 1227 Log.d(View.VIEW_LOG_TAG, "Sending drag-started to view: " + child); 1228 } 1229 1230 boolean canAccept = false; 1231 if (! mDragNotifiedChildren.contains(child)) { 1232 mDragNotifiedChildren.add(child); 1233 canAccept = child.dispatchDragEvent(mCurrentDrag); 1234 if (canAccept && !child.canAcceptDrag()) { 1235 child.mPrivateFlags2 |= View.DRAG_CAN_ACCEPT; 1236 child.refreshDrawableState(); 1237 } 1238 } 1239 return canAccept; 1240 } 1241 1242 @Override 1243 public void dispatchSystemUiVisibilityChanged(int visible) { 1244 super.dispatchSystemUiVisibilityChanged(visible); 1245 1246 final int count = mChildrenCount; 1247 final View[] children = mChildren; 1248 for (int i=0; i <count; i++) { 1249 final View child = children[i]; 1250 child.dispatchSystemUiVisibilityChanged(visible); 1251 } 1252 } 1253 1254 @Override 1255 void updateLocalSystemUiVisibility(int localValue, int localChanges) { 1256 super.updateLocalSystemUiVisibility(localValue, localChanges); 1257 1258 final int count = mChildrenCount; 1259 final View[] children = mChildren; 1260 for (int i=0; i <count; i++) { 1261 final View child = children[i]; 1262 child.updateLocalSystemUiVisibility(localValue, localChanges); 1263 } 1264 } 1265 1266 /** 1267 * {@inheritDoc} 1268 */ 1269 @Override 1270 public boolean dispatchKeyEventPreIme(KeyEvent event) { 1271 if ((mPrivateFlags & (FOCUSED | HAS_BOUNDS)) == (FOCUSED | HAS_BOUNDS)) { 1272 return super.dispatchKeyEventPreIme(event); 1273 } else if (mFocused != null && (mFocused.mPrivateFlags & HAS_BOUNDS) == HAS_BOUNDS) { 1274 return mFocused.dispatchKeyEventPreIme(event); 1275 } 1276 return false; 1277 } 1278 1279 /** 1280 * {@inheritDoc} 1281 */ 1282 @Override 1283 public boolean dispatchKeyEvent(KeyEvent event) { 1284 if (mInputEventConsistencyVerifier != null) { 1285 mInputEventConsistencyVerifier.onKeyEvent(event, 1); 1286 } 1287 1288 if ((mPrivateFlags & (FOCUSED | HAS_BOUNDS)) == (FOCUSED | HAS_BOUNDS)) { 1289 if (super.dispatchKeyEvent(event)) { 1290 return true; 1291 } 1292 } else if (mFocused != null && (mFocused.mPrivateFlags & HAS_BOUNDS) == HAS_BOUNDS) { 1293 if (mFocused.dispatchKeyEvent(event)) { 1294 return true; 1295 } 1296 } 1297 1298 if (mInputEventConsistencyVerifier != null) { 1299 mInputEventConsistencyVerifier.onUnhandledEvent(event, 1); 1300 } 1301 return false; 1302 } 1303 1304 /** 1305 * {@inheritDoc} 1306 */ 1307 @Override 1308 public boolean dispatchKeyShortcutEvent(KeyEvent event) { 1309 if ((mPrivateFlags & (FOCUSED | HAS_BOUNDS)) == (FOCUSED | HAS_BOUNDS)) { 1310 return super.dispatchKeyShortcutEvent(event); 1311 } else if (mFocused != null && (mFocused.mPrivateFlags & HAS_BOUNDS) == HAS_BOUNDS) { 1312 return mFocused.dispatchKeyShortcutEvent(event); 1313 } 1314 return false; 1315 } 1316 1317 /** 1318 * {@inheritDoc} 1319 */ 1320 @Override 1321 public boolean dispatchTrackballEvent(MotionEvent event) { 1322 if (mInputEventConsistencyVerifier != null) { 1323 mInputEventConsistencyVerifier.onTrackballEvent(event, 1); 1324 } 1325 1326 if ((mPrivateFlags & (FOCUSED | HAS_BOUNDS)) == (FOCUSED | HAS_BOUNDS)) { 1327 if (super.dispatchTrackballEvent(event)) { 1328 return true; 1329 } 1330 } else if (mFocused != null && (mFocused.mPrivateFlags & HAS_BOUNDS) == HAS_BOUNDS) { 1331 if (mFocused.dispatchTrackballEvent(event)) { 1332 return true; 1333 } 1334 } 1335 1336 if (mInputEventConsistencyVerifier != null) { 1337 mInputEventConsistencyVerifier.onUnhandledEvent(event, 1); 1338 } 1339 return false; 1340 } 1341 1342 /** 1343 * {@inheritDoc} 1344 */ 1345 @SuppressWarnings({"ConstantConditions"}) 1346 @Override 1347 protected boolean dispatchHoverEvent(MotionEvent event) { 1348 final int action = event.getAction(); 1349 1350 // First check whether the view group wants to intercept the hover event. 1351 final boolean interceptHover = onInterceptHoverEvent(event); 1352 event.setAction(action); // restore action in case it was changed 1353 1354 MotionEvent eventNoHistory = event; 1355 boolean handled = false; 1356 1357 // Send events to the hovered children and build a new list of hover targets until 1358 // one is found that handles the event. 1359 HoverTarget firstOldHoverTarget = mFirstHoverTarget; 1360 mFirstHoverTarget = null; 1361 if (!interceptHover && action != MotionEvent.ACTION_HOVER_EXIT) { 1362 final float x = event.getX(); 1363 final float y = event.getY(); 1364 final int childrenCount = mChildrenCount; 1365 if (childrenCount != 0) { 1366 final View[] children = mChildren; 1367 HoverTarget lastHoverTarget = null; 1368 for (int i = childrenCount - 1; i >= 0; i--) { 1369 final View child = children[i]; 1370 if (!canViewReceivePointerEvents(child) 1371 || !isTransformedTouchPointInView(x, y, child, null)) { 1372 continue; 1373 } 1374 1375 // Obtain a hover target for this child. Dequeue it from the 1376 // old hover target list if the child was previously hovered. 1377 HoverTarget hoverTarget = firstOldHoverTarget; 1378 final boolean wasHovered; 1379 for (HoverTarget predecessor = null; ;) { 1380 if (hoverTarget == null) { 1381 hoverTarget = HoverTarget.obtain(child); 1382 wasHovered = false; 1383 break; 1384 } 1385 1386 if (hoverTarget.child == child) { 1387 if (predecessor != null) { 1388 predecessor.next = hoverTarget.next; 1389 } else { 1390 firstOldHoverTarget = hoverTarget.next; 1391 } 1392 hoverTarget.next = null; 1393 wasHovered = true; 1394 break; 1395 } 1396 1397 predecessor = hoverTarget; 1398 hoverTarget = hoverTarget.next; 1399 } 1400 1401 // Enqueue the hover target onto the new hover target list. 1402 if (lastHoverTarget != null) { 1403 lastHoverTarget.next = hoverTarget; 1404 } else { 1405 lastHoverTarget = hoverTarget; 1406 mFirstHoverTarget = hoverTarget; 1407 } 1408 1409 // Dispatch the event to the child. 1410 if (action == MotionEvent.ACTION_HOVER_ENTER) { 1411 if (!wasHovered) { 1412 // Send the enter as is. 1413 handled |= dispatchTransformedGenericPointerEvent( 1414 event, child); // enter 1415 } 1416 } else if (action == MotionEvent.ACTION_HOVER_MOVE) { 1417 if (!wasHovered) { 1418 // Synthesize an enter from a move. 1419 eventNoHistory = obtainMotionEventNoHistoryOrSelf(eventNoHistory); 1420 eventNoHistory.setAction(MotionEvent.ACTION_HOVER_ENTER); 1421 handled |= dispatchTransformedGenericPointerEvent( 1422 eventNoHistory, child); // enter 1423 eventNoHistory.setAction(action); 1424 1425 handled |= dispatchTransformedGenericPointerEvent( 1426 eventNoHistory, child); // move 1427 } else { 1428 // Send the move as is. 1429 handled |= dispatchTransformedGenericPointerEvent(event, child); 1430 } 1431 } 1432 if (handled) { 1433 break; 1434 } 1435 } 1436 } 1437 } 1438 1439 // Send exit events to all previously hovered children that are no longer hovered. 1440 while (firstOldHoverTarget != null) { 1441 final View child = firstOldHoverTarget.child; 1442 1443 // Exit the old hovered child. 1444 if (action == MotionEvent.ACTION_HOVER_EXIT) { 1445 // Send the exit as is. 1446 handled |= dispatchTransformedGenericPointerEvent( 1447 event, child); // exit 1448 } else { 1449 // Synthesize an exit from a move or enter. 1450 // Ignore the result because hover focus has moved to a different view. 1451 if (action == MotionEvent.ACTION_HOVER_MOVE) { 1452 dispatchTransformedGenericPointerEvent( 1453 event, child); // move 1454 } 1455 eventNoHistory = obtainMotionEventNoHistoryOrSelf(eventNoHistory); 1456 eventNoHistory.setAction(MotionEvent.ACTION_HOVER_EXIT); 1457 dispatchTransformedGenericPointerEvent( 1458 eventNoHistory, child); // exit 1459 eventNoHistory.setAction(action); 1460 } 1461 1462 final HoverTarget nextOldHoverTarget = firstOldHoverTarget.next; 1463 firstOldHoverTarget.recycle(); 1464 firstOldHoverTarget = nextOldHoverTarget; 1465 } 1466 1467 // Send events to the view group itself if no children have handled it. 1468 boolean newHoveredSelf = !handled; 1469 if (newHoveredSelf == mHoveredSelf) { 1470 if (newHoveredSelf) { 1471 // Send event to the view group as before. 1472 handled |= super.dispatchHoverEvent(event); 1473 } 1474 } else { 1475 if (mHoveredSelf) { 1476 // Exit the view group. 1477 if (action == MotionEvent.ACTION_HOVER_EXIT) { 1478 // Send the exit as is. 1479 handled |= super.dispatchHoverEvent(event); // exit 1480 } else { 1481 // Synthesize an exit from a move or enter. 1482 // Ignore the result because hover focus is moving to a different view. 1483 if (action == MotionEvent.ACTION_HOVER_MOVE) { 1484 super.dispatchHoverEvent(event); // move 1485 } 1486 eventNoHistory = obtainMotionEventNoHistoryOrSelf(eventNoHistory); 1487 eventNoHistory.setAction(MotionEvent.ACTION_HOVER_EXIT); 1488 super.dispatchHoverEvent(eventNoHistory); // exit 1489 eventNoHistory.setAction(action); 1490 } 1491 mHoveredSelf = false; 1492 } 1493 1494 if (newHoveredSelf) { 1495 // Enter the view group. 1496 if (action == MotionEvent.ACTION_HOVER_ENTER) { 1497 // Send the enter as is. 1498 handled |= super.dispatchHoverEvent(event); // enter 1499 mHoveredSelf = true; 1500 } else if (action == MotionEvent.ACTION_HOVER_MOVE) { 1501 // Synthesize an enter from a move. 1502 eventNoHistory = obtainMotionEventNoHistoryOrSelf(eventNoHistory); 1503 eventNoHistory.setAction(MotionEvent.ACTION_HOVER_ENTER); 1504 handled |= super.dispatchHoverEvent(eventNoHistory); // enter 1505 eventNoHistory.setAction(action); 1506 1507 handled |= super.dispatchHoverEvent(eventNoHistory); // move 1508 mHoveredSelf = true; 1509 } 1510 } 1511 } 1512 1513 // Recycle the copy of the event that we made. 1514 if (eventNoHistory != event) { 1515 eventNoHistory.recycle(); 1516 } 1517 1518 // Done. 1519 return handled; 1520 } 1521 1522 /** @hide */ 1523 @Override 1524 protected boolean hasHoveredChild() { 1525 return mFirstHoverTarget != null; 1526 } 1527 1528 /** 1529 * Implement this method to intercept hover events before they are handled 1530 * by child views. 1531 * <p> 1532 * This method is called before dispatching a hover event to a child of 1533 * the view group or to the view group's own {@link #onHoverEvent} to allow 1534 * the view group a chance to intercept the hover event. 1535 * This method can also be used to watch all pointer motions that occur within 1536 * the bounds of the view group even when the pointer is hovering over 1537 * a child of the view group rather than over the view group itself. 1538 * </p><p> 1539 * The view group can prevent its children from receiving hover events by 1540 * implementing this method and returning <code>true</code> to indicate 1541 * that it would like to intercept hover events. The view group must 1542 * continuously return <code>true</code> from {@link #onInterceptHoverEvent} 1543 * for as long as it wishes to continue intercepting hover events from 1544 * its children. 1545 * </p><p> 1546 * Interception preserves the invariant that at most one view can be 1547 * hovered at a time by transferring hover focus from the currently hovered 1548 * child to the view group or vice-versa as needed. 1549 * </p><p> 1550 * If this method returns <code>true</code> and a child is already hovered, then the 1551 * child view will first receive a hover exit event and then the view group 1552 * itself will receive a hover enter event in {@link #onHoverEvent}. 1553 * Likewise, if this method had previously returned <code>true</code> to intercept hover 1554 * events and instead returns <code>false</code> while the pointer is hovering 1555 * within the bounds of one of a child, then the view group will first receive a 1556 * hover exit event in {@link #onHoverEvent} and then the hovered child will 1557 * receive a hover enter event. 1558 * </p><p> 1559 * The default implementation always returns false. 1560 * </p> 1561 * 1562 * @param event The motion event that describes the hover. 1563 * @return True if the view group would like to intercept the hover event 1564 * and prevent its children from receiving it. 1565 */ 1566 public boolean onInterceptHoverEvent(MotionEvent event) { 1567 return false; 1568 } 1569 1570 private static MotionEvent obtainMotionEventNoHistoryOrSelf(MotionEvent event) { 1571 if (event.getHistorySize() == 0) { 1572 return event; 1573 } 1574 return MotionEvent.obtainNoHistory(event); 1575 } 1576 1577 /** 1578 * {@inheritDoc} 1579 */ 1580 @Override 1581 protected boolean dispatchGenericPointerEvent(MotionEvent event) { 1582 // Send the event to the child under the pointer. 1583 final int childrenCount = mChildrenCount; 1584 if (childrenCount != 0) { 1585 final View[] children = mChildren; 1586 final float x = event.getX(); 1587 final float y = event.getY(); 1588 1589 for (int i = childrenCount - 1; i >= 0; i--) { 1590 final View child = children[i]; 1591 if (!canViewReceivePointerEvents(child) 1592 || !isTransformedTouchPointInView(x, y, child, null)) { 1593 continue; 1594 } 1595 1596 if (dispatchTransformedGenericPointerEvent(event, child)) { 1597 return true; 1598 } 1599 } 1600 } 1601 1602 // No child handled the event. Send it to this view group. 1603 return super.dispatchGenericPointerEvent(event); 1604 } 1605 1606 /** 1607 * {@inheritDoc} 1608 */ 1609 @Override 1610 protected boolean dispatchGenericFocusedEvent(MotionEvent event) { 1611 // Send the event to the focused child or to this view group if it has focus. 1612 if ((mPrivateFlags & (FOCUSED | HAS_BOUNDS)) == (FOCUSED | HAS_BOUNDS)) { 1613 return super.dispatchGenericFocusedEvent(event); 1614 } else if (mFocused != null && (mFocused.mPrivateFlags & HAS_BOUNDS) == HAS_BOUNDS) { 1615 return mFocused.dispatchGenericMotionEvent(event); 1616 } 1617 return false; 1618 } 1619 1620 /** 1621 * Dispatches a generic pointer event to a child, taking into account 1622 * transformations that apply to the child. 1623 * 1624 * @param event The event to send. 1625 * @param child The view to send the event to. 1626 * @return {@code true} if the child handled the event. 1627 */ 1628 private boolean dispatchTransformedGenericPointerEvent(MotionEvent event, View child) { 1629 final float offsetX = mScrollX - child.mLeft; 1630 final float offsetY = mScrollY - child.mTop; 1631 1632 boolean handled; 1633 if (!child.hasIdentityMatrix()) { 1634 MotionEvent transformedEvent = MotionEvent.obtain(event); 1635 transformedEvent.offsetLocation(offsetX, offsetY); 1636 transformedEvent.transform(child.getInverseMatrix()); 1637 handled = child.dispatchGenericMotionEvent(transformedEvent); 1638 transformedEvent.recycle(); 1639 } else { 1640 event.offsetLocation(offsetX, offsetY); 1641 handled = child.dispatchGenericMotionEvent(event); 1642 event.offsetLocation(-offsetX, -offsetY); 1643 } 1644 return handled; 1645 } 1646 1647 /** 1648 * {@inheritDoc} 1649 */ 1650 @Override 1651 public boolean dispatchTouchEvent(MotionEvent ev) { 1652 if (mInputEventConsistencyVerifier != null) { 1653 mInputEventConsistencyVerifier.onTouchEvent(ev, 1); 1654 } 1655 1656 boolean handled = false; 1657 if (onFilterTouchEventForSecurity(ev)) { 1658 final int action = ev.getAction(); 1659 final int actionMasked = action & MotionEvent.ACTION_MASK; 1660 1661 // Handle an initial down. 1662 if (actionMasked == MotionEvent.ACTION_DOWN) { 1663 // Throw away all previous state when starting a new touch gesture. 1664 // The framework may have dropped the up or cancel event for the previous gesture 1665 // due to an app switch, ANR, or some other state change. 1666 cancelAndClearTouchTargets(ev); 1667 resetTouchState(); 1668 } 1669 1670 // Check for interception. 1671 final boolean intercepted; 1672 if (actionMasked == MotionEvent.ACTION_DOWN 1673 || mFirstTouchTarget != null) { 1674 final boolean disallowIntercept = (mGroupFlags & FLAG_DISALLOW_INTERCEPT) != 0; 1675 if (!disallowIntercept) { 1676 intercepted = onInterceptTouchEvent(ev); 1677 ev.setAction(action); // restore action in case it was changed 1678 } else { 1679 intercepted = false; 1680 } 1681 } else { 1682 // There are no touch targets and this action is not an initial down 1683 // so this view group continues to intercept touches. 1684 intercepted = true; 1685 } 1686 1687 // Check for cancelation. 1688 final boolean canceled = resetCancelNextUpFlag(this) 1689 || actionMasked == MotionEvent.ACTION_CANCEL; 1690 1691 // Update list of touch targets for pointer down, if needed. 1692 final boolean split = (mGroupFlags & FLAG_SPLIT_MOTION_EVENTS) != 0; 1693 TouchTarget newTouchTarget = null; 1694 boolean alreadyDispatchedToNewTouchTarget = false; 1695 if (!canceled && !intercepted) { 1696 if (actionMasked == MotionEvent.ACTION_DOWN 1697 || (split && actionMasked == MotionEvent.ACTION_POINTER_DOWN) 1698 || actionMasked == MotionEvent.ACTION_HOVER_MOVE) { 1699 final int actionIndex = ev.getActionIndex(); // always 0 for down 1700 final int idBitsToAssign = split ? 1 << ev.getPointerId(actionIndex) 1701 : TouchTarget.ALL_POINTER_IDS; 1702 1703 // Clean up earlier touch targets for this pointer id in case they 1704 // have become out of sync. 1705 removePointersFromTouchTargets(idBitsToAssign); 1706 1707 final int childrenCount = mChildrenCount; 1708 if (childrenCount != 0) { 1709 // Find a child that can receive the event. 1710 // Scan children from front to back. 1711 final View[] children = mChildren; 1712 final float x = ev.getX(actionIndex); 1713 final float y = ev.getY(actionIndex); 1714 1715 for (int i = childrenCount - 1; i >= 0; i--) { 1716 final View child = children[i]; 1717 if (!canViewReceivePointerEvents(child) 1718 || !isTransformedTouchPointInView(x, y, child, null)) { 1719 continue; 1720 } 1721 1722 newTouchTarget = getTouchTarget(child); 1723 if (newTouchTarget != null) { 1724 // Child is already receiving touch within its bounds. 1725 // Give it the new pointer in addition to the ones it is handling. 1726 newTouchTarget.pointerIdBits |= idBitsToAssign; 1727 break; 1728 } 1729 1730 resetCancelNextUpFlag(child); 1731 if (dispatchTransformedTouchEvent(ev, false, child, idBitsToAssign)) { 1732 // Child wants to receive touch within its bounds. 1733 mLastTouchDownTime = ev.getDownTime(); 1734 mLastTouchDownIndex = i; 1735 mLastTouchDownX = ev.getX(); 1736 mLastTouchDownY = ev.getY(); 1737 newTouchTarget = addTouchTarget(child, idBitsToAssign); 1738 alreadyDispatchedToNewTouchTarget = true; 1739 break; 1740 } 1741 } 1742 } 1743 1744 if (newTouchTarget == null && mFirstTouchTarget != null) { 1745 // Did not find a child to receive the event. 1746 // Assign the pointer to the least recently added target. 1747 newTouchTarget = mFirstTouchTarget; 1748 while (newTouchTarget.next != null) { 1749 newTouchTarget = newTouchTarget.next; 1750 } 1751 newTouchTarget.pointerIdBits |= idBitsToAssign; 1752 } 1753 } 1754 } 1755 1756 // Dispatch to touch targets. 1757 if (mFirstTouchTarget == null) { 1758 // No touch targets so treat this as an ordinary view. 1759 handled = dispatchTransformedTouchEvent(ev, canceled, null, 1760 TouchTarget.ALL_POINTER_IDS); 1761 } else { 1762 // Dispatch to touch targets, excluding the new touch target if we already 1763 // dispatched to it. Cancel touch targets if necessary. 1764 TouchTarget predecessor = null; 1765 TouchTarget target = mFirstTouchTarget; 1766 while (target != null) { 1767 final TouchTarget next = target.next; 1768 if (alreadyDispatchedToNewTouchTarget && target == newTouchTarget) { 1769 handled = true; 1770 } else { 1771 final boolean cancelChild = resetCancelNextUpFlag(target.child) 1772 || intercepted; 1773 if (dispatchTransformedTouchEvent(ev, cancelChild, 1774 target.child, target.pointerIdBits)) { 1775 handled = true; 1776 } 1777 if (cancelChild) { 1778 if (predecessor == null) { 1779 mFirstTouchTarget = next; 1780 } else { 1781 predecessor.next = next; 1782 } 1783 target.recycle(); 1784 target = next; 1785 continue; 1786 } 1787 } 1788 predecessor = target; 1789 target = next; 1790 } 1791 } 1792 1793 // Update list of touch targets for pointer up or cancel, if needed. 1794 if (canceled 1795 || actionMasked == MotionEvent.ACTION_UP 1796 || actionMasked == MotionEvent.ACTION_HOVER_MOVE) { 1797 resetTouchState(); 1798 } else if (split && actionMasked == MotionEvent.ACTION_POINTER_UP) { 1799 final int actionIndex = ev.getActionIndex(); 1800 final int idBitsToRemove = 1 << ev.getPointerId(actionIndex); 1801 removePointersFromTouchTargets(idBitsToRemove); 1802 } 1803 } 1804 1805 if (!handled && mInputEventConsistencyVerifier != null) { 1806 mInputEventConsistencyVerifier.onUnhandledEvent(ev, 1); 1807 } 1808 return handled; 1809 } 1810 1811 /** 1812 * Resets all touch state in preparation for a new cycle. 1813 */ 1814 private void resetTouchState() { 1815 clearTouchTargets(); 1816 resetCancelNextUpFlag(this); 1817 mGroupFlags &= ~FLAG_DISALLOW_INTERCEPT; 1818 } 1819 1820 /** 1821 * Resets the cancel next up flag. 1822 * Returns true if the flag was previously set. 1823 */ 1824 private boolean resetCancelNextUpFlag(View view) { 1825 if ((view.mPrivateFlags & CANCEL_NEXT_UP_EVENT) != 0) { 1826 view.mPrivateFlags &= ~CANCEL_NEXT_UP_EVENT; 1827 return true; 1828 } 1829 return false; 1830 } 1831 1832 /** 1833 * Clears all touch targets. 1834 */ 1835 private void clearTouchTargets() { 1836 TouchTarget target = mFirstTouchTarget; 1837 if (target != null) { 1838 do { 1839 TouchTarget next = target.next; 1840 target.recycle(); 1841 target = next; 1842 } while (target != null); 1843 mFirstTouchTarget = null; 1844 } 1845 } 1846 1847 /** 1848 * Cancels and clears all touch targets. 1849 */ 1850 private void cancelAndClearTouchTargets(MotionEvent event) { 1851 if (mFirstTouchTarget != null) { 1852 boolean syntheticEvent = false; 1853 if (event == null) { 1854 final long now = SystemClock.uptimeMillis(); 1855 event = MotionEvent.obtain(now, now, 1856 MotionEvent.ACTION_CANCEL, 0.0f, 0.0f, 0); 1857 event.setSource(InputDevice.SOURCE_TOUCHSCREEN); 1858 syntheticEvent = true; 1859 } 1860 1861 for (TouchTarget target = mFirstTouchTarget; target != null; target = target.next) { 1862 resetCancelNextUpFlag(target.child); 1863 dispatchTransformedTouchEvent(event, true, target.child, target.pointerIdBits); 1864 } 1865 clearTouchTargets(); 1866 1867 if (syntheticEvent) { 1868 event.recycle(); 1869 } 1870 } 1871 } 1872 1873 /** 1874 * Gets the touch target for specified child view. 1875 * Returns null if not found. 1876 */ 1877 private TouchTarget getTouchTarget(View child) { 1878 for (TouchTarget target = mFirstTouchTarget; target != null; target = target.next) { 1879 if (target.child == child) { 1880 return target; 1881 } 1882 } 1883 return null; 1884 } 1885 1886 /** 1887 * Adds a touch target for specified child to the beginning of the list. 1888 * Assumes the target child is not already present. 1889 */ 1890 private TouchTarget addTouchTarget(View child, int pointerIdBits) { 1891 TouchTarget target = TouchTarget.obtain(child, pointerIdBits); 1892 target.next = mFirstTouchTarget; 1893 mFirstTouchTarget = target; 1894 return target; 1895 } 1896 1897 /** 1898 * Removes the pointer ids from consideration. 1899 */ 1900 private void removePointersFromTouchTargets(int pointerIdBits) { 1901 TouchTarget predecessor = null; 1902 TouchTarget target = mFirstTouchTarget; 1903 while (target != null) { 1904 final TouchTarget next = target.next; 1905 if ((target.pointerIdBits & pointerIdBits) != 0) { 1906 target.pointerIdBits &= ~pointerIdBits; 1907 if (target.pointerIdBits == 0) { 1908 if (predecessor == null) { 1909 mFirstTouchTarget = next; 1910 } else { 1911 predecessor.next = next; 1912 } 1913 target.recycle(); 1914 target = next; 1915 continue; 1916 } 1917 } 1918 predecessor = target; 1919 target = next; 1920 } 1921 } 1922 1923 /** 1924 * Returns true if a child view can receive pointer events. 1925 * @hide 1926 */ 1927 private static boolean canViewReceivePointerEvents(View child) { 1928 return (child.mViewFlags & VISIBILITY_MASK) == VISIBLE 1929 || child.getAnimation() != null; 1930 } 1931 1932 /** 1933 * Returns true if a child view contains the specified point when transformed 1934 * into its coordinate space. 1935 * Child must not be null. 1936 * @hide 1937 */ 1938 protected boolean isTransformedTouchPointInView(float x, float y, View child, 1939 PointF outLocalPoint) { 1940 float localX = x + mScrollX - child.mLeft; 1941 float localY = y + mScrollY - child.mTop; 1942 if (! child.hasIdentityMatrix() && mAttachInfo != null) { 1943 final float[] localXY = mAttachInfo.mTmpTransformLocation; 1944 localXY[0] = localX; 1945 localXY[1] = localY; 1946 child.getInverseMatrix().mapPoints(localXY); 1947 localX = localXY[0]; 1948 localY = localXY[1]; 1949 } 1950 final boolean isInView = child.pointInView(localX, localY); 1951 if (isInView && outLocalPoint != null) { 1952 outLocalPoint.set(localX, localY); 1953 } 1954 return isInView; 1955 } 1956 1957 /** 1958 * Transforms a motion event into the coordinate space of a particular child view, 1959 * filters out irrelevant pointer ids, and overrides its action if necessary. 1960 * If child is null, assumes the MotionEvent will be sent to this ViewGroup instead. 1961 */ 1962 private boolean dispatchTransformedTouchEvent(MotionEvent event, boolean cancel, 1963 View child, int desiredPointerIdBits) { 1964 final boolean handled; 1965 1966 // Canceling motions is a special case. We don't need to perform any transformations 1967 // or filtering. The important part is the action, not the contents. 1968 final int oldAction = event.getAction(); 1969 if (cancel || oldAction == MotionEvent.ACTION_CANCEL) { 1970 event.setAction(MotionEvent.ACTION_CANCEL); 1971 if (child == null) { 1972 handled = super.dispatchTouchEvent(event); 1973 } else { 1974 handled = child.dispatchTouchEvent(event); 1975 } 1976 event.setAction(oldAction); 1977 return handled; 1978 } 1979 1980 // Calculate the number of pointers to deliver. 1981 final int oldPointerIdBits = event.getPointerIdBits(); 1982 final int newPointerIdBits = oldPointerIdBits & desiredPointerIdBits; 1983 1984 // If for some reason we ended up in an inconsistent state where it looks like we 1985 // might produce a motion event with no pointers in it, then drop the event. 1986 if (newPointerIdBits == 0) { 1987 return false; 1988 } 1989 1990 // If the number of pointers is the same and we don't need to perform any fancy 1991 // irreversible transformations, then we can reuse the motion event for this 1992 // dispatch as long as we are careful to revert any changes we make. 1993 // Otherwise we need to make a copy. 1994 final MotionEvent transformedEvent; 1995 if (newPointerIdBits == oldPointerIdBits) { 1996 if (child == null || child.hasIdentityMatrix()) { 1997 if (child == null) { 1998 handled = super.dispatchTouchEvent(event); 1999 } else { 2000 final float offsetX = mScrollX - child.mLeft; 2001 final float offsetY = mScrollY - child.mTop; 2002 event.offsetLocation(offsetX, offsetY); 2003 2004 handled = child.dispatchTouchEvent(event); 2005 2006 event.offsetLocation(-offsetX, -offsetY); 2007 } 2008 return handled; 2009 } 2010 transformedEvent = MotionEvent.obtain(event); 2011 } else { 2012 transformedEvent = event.split(newPointerIdBits); 2013 } 2014 2015 // Perform any necessary transformations and dispatch. 2016 if (child == null) { 2017 handled = super.dispatchTouchEvent(transformedEvent); 2018 } else { 2019 final float offsetX = mScrollX - child.mLeft; 2020 final float offsetY = mScrollY - child.mTop; 2021 transformedEvent.offsetLocation(offsetX, offsetY); 2022 if (! child.hasIdentityMatrix()) { 2023 transformedEvent.transform(child.getInverseMatrix()); 2024 } 2025 2026 handled = child.dispatchTouchEvent(transformedEvent); 2027 } 2028 2029 // Done. 2030 transformedEvent.recycle(); 2031 return handled; 2032 } 2033 2034 /** 2035 * Enable or disable the splitting of MotionEvents to multiple children during touch event 2036 * dispatch. This behavior is enabled by default for applications that target an 2037 * SDK version of {@link Build.VERSION_CODES#HONEYCOMB} or newer. 2038 * 2039 * <p>When this option is enabled MotionEvents may be split and dispatched to different child 2040 * views depending on where each pointer initially went down. This allows for user interactions 2041 * such as scrolling two panes of content independently, chording of buttons, and performing 2042 * independent gestures on different pieces of content. 2043 * 2044 * @param split <code>true</code> to allow MotionEvents to be split and dispatched to multiple 2045 * child views. <code>false</code> to only allow one child view to be the target of 2046 * any MotionEvent received by this ViewGroup. 2047 */ 2048 public void setMotionEventSplittingEnabled(boolean split) { 2049 // TODO Applications really shouldn't change this setting mid-touch event, 2050 // but perhaps this should handle that case and send ACTION_CANCELs to any child views 2051 // with gestures in progress when this is changed. 2052 if (split) { 2053 mGroupFlags |= FLAG_SPLIT_MOTION_EVENTS; 2054 } else { 2055 mGroupFlags &= ~FLAG_SPLIT_MOTION_EVENTS; 2056 } 2057 } 2058 2059 /** 2060 * Returns true if MotionEvents dispatched to this ViewGroup can be split to multiple children. 2061 * @return true if MotionEvents dispatched to this ViewGroup can be split to multiple children. 2062 */ 2063 public boolean isMotionEventSplittingEnabled() { 2064 return (mGroupFlags & FLAG_SPLIT_MOTION_EVENTS) == FLAG_SPLIT_MOTION_EVENTS; 2065 } 2066 2067 /** 2068 * {@inheritDoc} 2069 */ 2070 public void requestDisallowInterceptTouchEvent(boolean disallowIntercept) { 2071 2072 if (disallowIntercept == ((mGroupFlags & FLAG_DISALLOW_INTERCEPT) != 0)) { 2073 // We're already in this state, assume our ancestors are too 2074 return; 2075 } 2076 2077 if (disallowIntercept) { 2078 mGroupFlags |= FLAG_DISALLOW_INTERCEPT; 2079 } else { 2080 mGroupFlags &= ~FLAG_DISALLOW_INTERCEPT; 2081 } 2082 2083 // Pass it up to our parent 2084 if (mParent != null) { 2085 mParent.requestDisallowInterceptTouchEvent(disallowIntercept); 2086 } 2087 } 2088 2089 /** 2090 * Implement this method to intercept all touch screen motion events. This 2091 * allows you to watch events as they are dispatched to your children, and 2092 * take ownership of the current gesture at any point. 2093 * 2094 * <p>Using this function takes some care, as it has a fairly complicated 2095 * interaction with {@link View#onTouchEvent(MotionEvent) 2096 * View.onTouchEvent(MotionEvent)}, and using it requires implementing 2097 * that method as well as this one in the correct way. Events will be 2098 * received in the following order: 2099 * 2100 * <ol> 2101 * <li> You will receive the down event here. 2102 * <li> The down event will be handled either by a child of this view 2103 * group, or given to your own onTouchEvent() method to handle; this means 2104 * you should implement onTouchEvent() to return true, so you will 2105 * continue to see the rest of the gesture (instead of looking for 2106 * a parent view to handle it). Also, by returning true from 2107 * onTouchEvent(), you will not receive any following 2108 * events in onInterceptTouchEvent() and all touch processing must 2109 * happen in onTouchEvent() like normal. 2110 * <li> For as long as you return false from this function, each following 2111 * event (up to and including the final up) will be delivered first here 2112 * and then to the target's onTouchEvent(). 2113 * <li> If you return true from here, you will not receive any 2114 * following events: the target view will receive the same event but 2115 * with the action {@link MotionEvent#ACTION_CANCEL}, and all further 2116 * events will be delivered to your onTouchEvent() method and no longer 2117 * appear here. 2118 * </ol> 2119 * 2120 * @param ev The motion event being dispatched down the hierarchy. 2121 * @return Return true to steal motion events from the children and have 2122 * them dispatched to this ViewGroup through onTouchEvent(). 2123 * The current target will receive an ACTION_CANCEL event, and no further 2124 * messages will be delivered here. 2125 */ 2126 public boolean onInterceptTouchEvent(MotionEvent ev) { 2127 return false; 2128 } 2129 2130 /** 2131 * {@inheritDoc} 2132 * 2133 * Looks for a view to give focus to respecting the setting specified by 2134 * {@link #getDescendantFocusability()}. 2135 * 2136 * Uses {@link #onRequestFocusInDescendants(int, android.graphics.Rect)} to 2137 * find focus within the children of this group when appropriate. 2138 * 2139 * @see #FOCUS_BEFORE_DESCENDANTS 2140 * @see #FOCUS_AFTER_DESCENDANTS 2141 * @see #FOCUS_BLOCK_DESCENDANTS 2142 * @see #onRequestFocusInDescendants(int, android.graphics.Rect) 2143 */ 2144 @Override 2145 public boolean requestFocus(int direction, Rect previouslyFocusedRect) { 2146 if (DBG) { 2147 System.out.println(this + " ViewGroup.requestFocus direction=" 2148 + direction); 2149 } 2150 int descendantFocusability = getDescendantFocusability(); 2151 2152 switch (descendantFocusability) { 2153 case FOCUS_BLOCK_DESCENDANTS: 2154 return super.requestFocus(direction, previouslyFocusedRect); 2155 case FOCUS_BEFORE_DESCENDANTS: { 2156 final boolean took = super.requestFocus(direction, previouslyFocusedRect); 2157 return took ? took : onRequestFocusInDescendants(direction, previouslyFocusedRect); 2158 } 2159 case FOCUS_AFTER_DESCENDANTS: { 2160 final boolean took = onRequestFocusInDescendants(direction, previouslyFocusedRect); 2161 return took ? took : super.requestFocus(direction, previouslyFocusedRect); 2162 } 2163 default: 2164 throw new IllegalStateException("descendant focusability must be " 2165 + "one of FOCUS_BEFORE_DESCENDANTS, FOCUS_AFTER_DESCENDANTS, FOCUS_BLOCK_DESCENDANTS " 2166 + "but is " + descendantFocusability); 2167 } 2168 } 2169 2170 /** 2171 * Look for a descendant to call {@link View#requestFocus} on. 2172 * Called by {@link ViewGroup#requestFocus(int, android.graphics.Rect)} 2173 * when it wants to request focus within its children. Override this to 2174 * customize how your {@link ViewGroup} requests focus within its children. 2175 * @param direction One of FOCUS_UP, FOCUS_DOWN, FOCUS_LEFT, and FOCUS_RIGHT 2176 * @param previouslyFocusedRect The rectangle (in this View's coordinate system) 2177 * to give a finer grained hint about where focus is coming from. May be null 2178 * if there is no hint. 2179 * @return Whether focus was taken. 2180 */ 2181 @SuppressWarnings({"ConstantConditions"}) 2182 protected boolean onRequestFocusInDescendants(int direction, 2183 Rect previouslyFocusedRect) { 2184 int index; 2185 int increment; 2186 int end; 2187 int count = mChildrenCount; 2188 if ((direction & FOCUS_FORWARD) != 0) { 2189 index = 0; 2190 increment = 1; 2191 end = count; 2192 } else { 2193 index = count - 1; 2194 increment = -1; 2195 end = -1; 2196 } 2197 final View[] children = mChildren; 2198 for (int i = index; i != end; i += increment) { 2199 View child = children[i]; 2200 if ((child.mViewFlags & VISIBILITY_MASK) == VISIBLE) { 2201 if (child.requestFocus(direction, previouslyFocusedRect)) { 2202 return true; 2203 } 2204 } 2205 } 2206 return false; 2207 } 2208 2209 /** 2210 * {@inheritDoc} 2211 * 2212 * @hide 2213 */ 2214 @Override 2215 public void dispatchStartTemporaryDetach() { 2216 super.dispatchStartTemporaryDetach(); 2217 final int count = mChildrenCount; 2218 final View[] children = mChildren; 2219 for (int i = 0; i < count; i++) { 2220 children[i].dispatchStartTemporaryDetach(); 2221 } 2222 } 2223 2224 /** 2225 * {@inheritDoc} 2226 * 2227 * @hide 2228 */ 2229 @Override 2230 public void dispatchFinishTemporaryDetach() { 2231 super.dispatchFinishTemporaryDetach(); 2232 final int count = mChildrenCount; 2233 final View[] children = mChildren; 2234 for (int i = 0; i < count; i++) { 2235 children[i].dispatchFinishTemporaryDetach(); 2236 } 2237 } 2238 2239 /** 2240 * {@inheritDoc} 2241 */ 2242 @Override 2243 void dispatchAttachedToWindow(AttachInfo info, int visibility) { 2244 mGroupFlags |= FLAG_PREVENT_DISPATCH_ATTACHED_TO_WINDOW; 2245 super.dispatchAttachedToWindow(info, visibility); 2246 mGroupFlags &= ~FLAG_PREVENT_DISPATCH_ATTACHED_TO_WINDOW; 2247 2248 visibility |= mViewFlags & VISIBILITY_MASK; 2249 2250 final int count = mChildrenCount; 2251 final View[] children = mChildren; 2252 for (int i = 0; i < count; i++) { 2253 children[i].dispatchAttachedToWindow(info, visibility); 2254 } 2255 } 2256 2257 @Override 2258 boolean dispatchPopulateAccessibilityEventInternal(AccessibilityEvent event) { 2259 boolean handled = super.dispatchPopulateAccessibilityEventInternal(event); 2260 if (handled) { 2261 return handled; 2262 } 2263 // Let our children have a shot in populating the event. 2264 for (int i = 0, count = getChildCount(); i < count; i++) { 2265 View child = getChildAt(i); 2266 if ((child.mViewFlags & VISIBILITY_MASK) == VISIBLE) { 2267 handled = getChildAt(i).dispatchPopulateAccessibilityEvent(event); 2268 if (handled) { 2269 return handled; 2270 } 2271 } 2272 } 2273 return false; 2274 } 2275 2276 @Override 2277 void onInitializeAccessibilityNodeInfoInternal(AccessibilityNodeInfo info) { 2278 super.onInitializeAccessibilityNodeInfoInternal(info); 2279 info.setClassName(ViewGroup.class.getName()); 2280 for (int i = 0, count = mChildrenCount; i < count; i++) { 2281 View child = mChildren[i]; 2282 if ((child.mViewFlags & VISIBILITY_MASK) == VISIBLE 2283 && (child.mPrivateFlags & IS_ROOT_NAMESPACE) == 0) { 2284 info.addChild(child); 2285 } 2286 } 2287 } 2288 2289 @Override 2290 void onInitializeAccessibilityEventInternal(AccessibilityEvent event) { 2291 super.onInitializeAccessibilityEventInternal(event); 2292 event.setClassName(ViewGroup.class.getName()); 2293 } 2294 2295 /** 2296 * {@inheritDoc} 2297 */ 2298 @Override 2299 void dispatchDetachedFromWindow() { 2300 // If we still have a touch target, we are still in the process of 2301 // dispatching motion events to a child; we need to get rid of that 2302 // child to avoid dispatching events to it after the window is torn 2303 // down. To make sure we keep the child in a consistent state, we 2304 // first send it an ACTION_CANCEL motion event. 2305 cancelAndClearTouchTargets(null); 2306 2307 // In case view is detached while transition is running 2308 mLayoutSuppressed = false; 2309 2310 // Tear down our drag tracking 2311 mDragNotifiedChildren = null; 2312 if (mCurrentDrag != null) { 2313 mCurrentDrag.recycle(); 2314 mCurrentDrag = null; 2315 } 2316 2317 final int count = mChildrenCount; 2318 final View[] children = mChildren; 2319 for (int i = 0; i < count; i++) { 2320 children[i].dispatchDetachedFromWindow(); 2321 } 2322 super.dispatchDetachedFromWindow(); 2323 } 2324 2325 /** 2326 * {@inheritDoc} 2327 */ 2328 @Override 2329 public void setPadding(int left, int top, int right, int bottom) { 2330 super.setPadding(left, top, right, bottom); 2331 2332 if ((mPaddingLeft | mPaddingTop | mPaddingRight | mPaddingBottom) != 0) { 2333 mGroupFlags |= FLAG_PADDING_NOT_NULL; 2334 } else { 2335 mGroupFlags &= ~FLAG_PADDING_NOT_NULL; 2336 } 2337 } 2338 2339 /** 2340 * {@inheritDoc} 2341 */ 2342 @Override 2343 protected void dispatchSaveInstanceState(SparseArray<Parcelable> container) { 2344 super.dispatchSaveInstanceState(container); 2345 final int count = mChildrenCount; 2346 final View[] children = mChildren; 2347 for (int i = 0; i < count; i++) { 2348 View c = children[i]; 2349 if ((c.mViewFlags & PARENT_SAVE_DISABLED_MASK) != PARENT_SAVE_DISABLED) { 2350 c.dispatchSaveInstanceState(container); 2351 } 2352 } 2353 } 2354 2355 /** 2356 * Perform dispatching of a {@link #saveHierarchyState(android.util.SparseArray)} freeze()} 2357 * to only this view, not to its children. For use when overriding 2358 * {@link #dispatchSaveInstanceState(android.util.SparseArray)} dispatchFreeze()} to allow 2359 * subclasses to freeze their own state but not the state of their children. 2360 * 2361 * @param container the container 2362 */ 2363 protected void dispatchFreezeSelfOnly(SparseArray<Parcelable> container) { 2364 super.dispatchSaveInstanceState(container); 2365 } 2366 2367 /** 2368 * {@inheritDoc} 2369 */ 2370 @Override 2371 protected void dispatchRestoreInstanceState(SparseArray<Parcelable> container) { 2372 super.dispatchRestoreInstanceState(container); 2373 final int count = mChildrenCount; 2374 final View[] children = mChildren; 2375 for (int i = 0; i < count; i++) { 2376 View c = children[i]; 2377 if ((c.mViewFlags & PARENT_SAVE_DISABLED_MASK) != PARENT_SAVE_DISABLED) { 2378 c.dispatchRestoreInstanceState(container); 2379 } 2380 } 2381 } 2382 2383 /** 2384 * Perform dispatching of a {@link #restoreHierarchyState(android.util.SparseArray)} 2385 * to only this view, not to its children. For use when overriding 2386 * {@link #dispatchRestoreInstanceState(android.util.SparseArray)} to allow 2387 * subclasses to thaw their own state but not the state of their children. 2388 * 2389 * @param container the container 2390 */ 2391 protected void dispatchThawSelfOnly(SparseArray<Parcelable> container) { 2392 super.dispatchRestoreInstanceState(container); 2393 } 2394 2395 /** 2396 * Enables or disables the drawing cache for each child of this view group. 2397 * 2398 * @param enabled true to enable the cache, false to dispose of it 2399 */ 2400 protected void setChildrenDrawingCacheEnabled(boolean enabled) { 2401 if (enabled || (mPersistentDrawingCache & PERSISTENT_ALL_CACHES) != PERSISTENT_ALL_CACHES) { 2402 final View[] children = mChildren; 2403 final int count = mChildrenCount; 2404 for (int i = 0; i < count; i++) { 2405 children[i].setDrawingCacheEnabled(enabled); 2406 } 2407 } 2408 } 2409 2410 @Override 2411 protected void onAnimationStart() { 2412 super.onAnimationStart(); 2413 2414 // When this ViewGroup's animation starts, build the cache for the children 2415 if ((mGroupFlags & FLAG_ANIMATION_CACHE) == FLAG_ANIMATION_CACHE) { 2416 final int count = mChildrenCount; 2417 final View[] children = mChildren; 2418 final boolean buildCache = !isHardwareAccelerated(); 2419 2420 for (int i = 0; i < count; i++) { 2421 final View child = children[i]; 2422 if ((child.mViewFlags & VISIBILITY_MASK) == VISIBLE) { 2423 child.setDrawingCacheEnabled(true); 2424 if (buildCache) { 2425 child.buildDrawingCache(true); 2426 } 2427 } 2428 } 2429 2430 mGroupFlags |= FLAG_CHILDREN_DRAWN_WITH_CACHE; 2431 } 2432 } 2433 2434 @Override 2435 protected void onAnimationEnd() { 2436 super.onAnimationEnd(); 2437 2438 // When this ViewGroup's animation ends, destroy the cache of the children 2439 if ((mGroupFlags & FLAG_ANIMATION_CACHE) == FLAG_ANIMATION_CACHE) { 2440 mGroupFlags &= ~FLAG_CHILDREN_DRAWN_WITH_CACHE; 2441 2442 if ((mPersistentDrawingCache & PERSISTENT_ANIMATION_CACHE) == 0) { 2443 setChildrenDrawingCacheEnabled(false); 2444 } 2445 } 2446 } 2447 2448 @Override 2449 Bitmap createSnapshot(Bitmap.Config quality, int backgroundColor, boolean skipChildren) { 2450 int count = mChildrenCount; 2451 int[] visibilities = null; 2452 2453 if (skipChildren) { 2454 visibilities = new int[count]; 2455 for (int i = 0; i < count; i++) { 2456 View child = getChildAt(i); 2457 visibilities[i] = child.getVisibility(); 2458 if (visibilities[i] == View.VISIBLE) { 2459 child.setVisibility(INVISIBLE); 2460 } 2461 } 2462 } 2463 2464 Bitmap b = super.createSnapshot(quality, backgroundColor, skipChildren); 2465 2466 if (skipChildren) { 2467 for (int i = 0; i < count; i++) { 2468 getChildAt(i).setVisibility(visibilities[i]); 2469 } 2470 } 2471 2472 return b; 2473 } 2474 2475 /** 2476 * {@inheritDoc} 2477 */ 2478 @Override 2479 protected void dispatchDraw(Canvas canvas) { 2480 final int count = mChildrenCount; 2481 final View[] children = mChildren; 2482 int flags = mGroupFlags; 2483 2484 if ((flags & FLAG_RUN_ANIMATION) != 0 && canAnimate()) { 2485 final boolean cache = (mGroupFlags & FLAG_ANIMATION_CACHE) == FLAG_ANIMATION_CACHE; 2486 2487 final boolean buildCache = !isHardwareAccelerated(); 2488 for (int i = 0; i < count; i++) { 2489 final View child = children[i]; 2490 if ((child.mViewFlags & VISIBILITY_MASK) == VISIBLE) { 2491 final LayoutParams params = child.getLayoutParams(); 2492 attachLayoutAnimationParameters(child, params, i, count); 2493 bindLayoutAnimation(child); 2494 if (cache) { 2495 child.setDrawingCacheEnabled(true); 2496 if (buildCache) { 2497 child.buildDrawingCache(true); 2498 } 2499 } 2500 } 2501 } 2502 2503 final LayoutAnimationController controller = mLayoutAnimationController; 2504 if (controller.willOverlap()) { 2505 mGroupFlags |= FLAG_OPTIMIZE_INVALIDATE; 2506 } 2507 2508 controller.start(); 2509 2510 mGroupFlags &= ~FLAG_RUN_ANIMATION; 2511 mGroupFlags &= ~FLAG_ANIMATION_DONE; 2512 2513 if (cache) { 2514 mGroupFlags |= FLAG_CHILDREN_DRAWN_WITH_CACHE; 2515 } 2516 2517 if (mAnimationListener != null) { 2518 mAnimationListener.onAnimationStart(controller.getAnimation()); 2519 } 2520 } 2521 2522 int saveCount = 0; 2523 final boolean clipToPadding = (flags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK; 2524 if (clipToPadding) { 2525 saveCount = canvas.save(); 2526 canvas.clipRect(mScrollX + mPaddingLeft, mScrollY + mPaddingTop, 2527 mScrollX + mRight - mLeft - mPaddingRight, 2528 mScrollY + mBottom - mTop - mPaddingBottom); 2529 2530 } 2531 2532 // We will draw our child's animation, let's reset the flag 2533 mPrivateFlags &= ~DRAW_ANIMATION; 2534 mGroupFlags &= ~FLAG_INVALIDATE_REQUIRED; 2535 2536 boolean more = false; 2537 final long drawingTime = getDrawingTime(); 2538 2539 if ((flags & FLAG_USE_CHILD_DRAWING_ORDER) == 0) { 2540 for (int i = 0; i < count; i++) { 2541 final View child = children[i]; 2542 if ((child.mViewFlags & VISIBILITY_MASK) == VISIBLE || child.getAnimation() != null) { 2543 more |= drawChild(canvas, child, drawingTime); 2544 } 2545 } 2546 } else { 2547 for (int i = 0; i < count; i++) { 2548 final View child = children[getChildDrawingOrder(count, i)]; 2549 if ((child.mViewFlags & VISIBILITY_MASK) == VISIBLE || child.getAnimation() != null) { 2550 more |= drawChild(canvas, child, drawingTime); 2551 } 2552 } 2553 } 2554 2555 // Draw any disappearing views that have animations 2556 if (mDisappearingChildren != null) { 2557 final ArrayList<View> disappearingChildren = mDisappearingChildren; 2558 final int disappearingCount = disappearingChildren.size() - 1; 2559 // Go backwards -- we may delete as animations finish 2560 for (int i = disappearingCount; i >= 0; i--) { 2561 final View child = disappearingChildren.get(i); 2562 more |= drawChild(canvas, child, drawingTime); 2563 } 2564 } 2565 2566 if (clipToPadding) { 2567 canvas.restoreToCount(saveCount); 2568 } 2569 2570 // mGroupFlags might have been updated by drawChild() 2571 flags = mGroupFlags; 2572 2573 if ((flags & FLAG_INVALIDATE_REQUIRED) == FLAG_INVALIDATE_REQUIRED) { 2574 invalidate(true); 2575 } 2576 2577 if ((flags & FLAG_ANIMATION_DONE) == 0 && (flags & FLAG_NOTIFY_ANIMATION_LISTENER) == 0 && 2578 mLayoutAnimationController.isDone() && !more) { 2579 // We want to erase the drawing cache and notify the listener after the 2580 // next frame is drawn because one extra invalidate() is caused by 2581 // drawChild() after the animation is over 2582 mGroupFlags |= FLAG_NOTIFY_ANIMATION_LISTENER; 2583 final Runnable end = new Runnable() { 2584 public void run() { 2585 notifyAnimationListener(); 2586 } 2587 }; 2588 post(end); 2589 } 2590 } 2591 2592 /** 2593 * Returns the index of the child to draw for this iteration. Override this 2594 * if you want to change the drawing order of children. By default, it 2595 * returns i. 2596 * <p> 2597 * NOTE: In order for this method to be called, you must enable child ordering 2598 * first by calling {@link #setChildrenDrawingOrderEnabled(boolean)}. 2599 * 2600 * @param i The current iteration. 2601 * @return The index of the child to draw this iteration. 2602 * 2603 * @see #setChildrenDrawingOrderEnabled(boolean) 2604 * @see #isChildrenDrawingOrderEnabled() 2605 */ 2606 protected int getChildDrawingOrder(int childCount, int i) { 2607 return i; 2608 } 2609 2610 private void notifyAnimationListener() { 2611 mGroupFlags &= ~FLAG_NOTIFY_ANIMATION_LISTENER; 2612 mGroupFlags |= FLAG_ANIMATION_DONE; 2613 2614 if (mAnimationListener != null) { 2615 final Runnable end = new Runnable() { 2616 public void run() { 2617 mAnimationListener.onAnimationEnd(mLayoutAnimationController.getAnimation()); 2618 } 2619 }; 2620 post(end); 2621 } 2622 2623 if ((mGroupFlags & FLAG_ANIMATION_CACHE) == FLAG_ANIMATION_CACHE) { 2624 mGroupFlags &= ~FLAG_CHILDREN_DRAWN_WITH_CACHE; 2625 if ((mPersistentDrawingCache & PERSISTENT_ANIMATION_CACHE) == 0) { 2626 setChildrenDrawingCacheEnabled(false); 2627 } 2628 } 2629 2630 invalidate(true); 2631 } 2632 2633 /** 2634 * This method is used to cause children of this ViewGroup to restore or recreate their 2635 * display lists. It is called by getDisplayList() when the parent ViewGroup does not need 2636 * to recreate its own display list, which would happen if it went through the normal 2637 * draw/dispatchDraw mechanisms. 2638 * 2639 * @hide 2640 */ 2641 @Override 2642 protected void dispatchGetDisplayList() { 2643 final int count = mChildrenCount; 2644 final View[] children = mChildren; 2645 for (int i = 0; i < count; i++) { 2646 final View child = children[i]; 2647 if (((child.mViewFlags & VISIBILITY_MASK) == VISIBLE || child.getAnimation() != null) && 2648 child.hasStaticLayer()) { 2649 child.mRecreateDisplayList = (child.mPrivateFlags & INVALIDATED) == INVALIDATED; 2650 child.mPrivateFlags &= ~INVALIDATED; 2651 child.getDisplayList(); 2652 child.mRecreateDisplayList = false; 2653 } 2654 } 2655 } 2656 2657 /** 2658 * Draw one child of this View Group. This method is responsible for getting 2659 * the canvas in the right state. This includes clipping, translating so 2660 * that the child's scrolled origin is at 0, 0, and applying any animation 2661 * transformations. 2662 * 2663 * @param canvas The canvas on which to draw the child 2664 * @param child Who to draw 2665 * @param drawingTime The time at which draw is occurring 2666 * @return True if an invalidate() was issued 2667 */ 2668 protected boolean drawChild(Canvas canvas, View child, long drawingTime) { 2669 return child.draw(canvas, this, drawingTime); 2670 } 2671 2672 /** 2673 * 2674 * @param enabled True if children should be drawn with layers, false otherwise. 2675 * 2676 * @hide 2677 */ 2678 public void setChildrenLayersEnabled(boolean enabled) { 2679 if (enabled != mDrawLayers) { 2680 mDrawLayers = enabled; 2681 invalidate(true); 2682 2683 boolean flushLayers = !enabled; 2684 AttachInfo info = mAttachInfo; 2685 if (info != null && info.mHardwareRenderer != null && 2686 info.mHardwareRenderer.isEnabled()) { 2687 if (!info.mHardwareRenderer.validate()) { 2688 flushLayers = false; 2689 } 2690 } else { 2691 flushLayers = false; 2692 } 2693 2694 // We need to invalidate any child with a layer. For instance, 2695 // if a child is backed by a hardware layer and we disable layers 2696 // the child is marked as not dirty (flags cleared the last time 2697 // the child was drawn inside its layer.) However, that child might 2698 // never have created its own display list or have an obsolete 2699 // display list. By invalidating the child we ensure the display 2700 // list is in sync with the content of the hardware layer. 2701 for (int i = 0; i < mChildrenCount; i++) { 2702 View child = mChildren[i]; 2703 if (child.mLayerType != LAYER_TYPE_NONE) { 2704 if (flushLayers) child.flushLayer(); 2705 child.invalidate(true); 2706 } 2707 } 2708 } 2709 } 2710 2711 /** 2712 * By default, children are clipped to their bounds before drawing. This 2713 * allows view groups to override this behavior for animations, etc. 2714 * 2715 * @param clipChildren true to clip children to their bounds, 2716 * false otherwise 2717 * @attr ref android.R.styleable#ViewGroup_clipChildren 2718 */ 2719 public void setClipChildren(boolean clipChildren) { 2720 setBooleanFlag(FLAG_CLIP_CHILDREN, clipChildren); 2721 } 2722 2723 /** 2724 * By default, children are clipped to the padding of the ViewGroup. This 2725 * allows view groups to override this behavior 2726 * 2727 * @param clipToPadding true to clip children to the padding of the 2728 * group, false otherwise 2729 * @attr ref android.R.styleable#ViewGroup_clipToPadding 2730 */ 2731 public void setClipToPadding(boolean clipToPadding) { 2732 setBooleanFlag(FLAG_CLIP_TO_PADDING, clipToPadding); 2733 } 2734 2735 /** 2736 * {@inheritDoc} 2737 */ 2738 @Override 2739 public void dispatchSetSelected(boolean selected) { 2740 final View[] children = mChildren; 2741 final int count = mChildrenCount; 2742 for (int i = 0; i < count; i++) { 2743 children[i].setSelected(selected); 2744 } 2745 } 2746 2747 /** 2748 * {@inheritDoc} 2749 */ 2750 @Override 2751 public void dispatchSetActivated(boolean activated) { 2752 final View[] children = mChildren; 2753 final int count = mChildrenCount; 2754 for (int i = 0; i < count; i++) { 2755 children[i].setActivated(activated); 2756 } 2757 } 2758 2759 @Override 2760 protected void dispatchSetPressed(boolean pressed) { 2761 final View[] children = mChildren; 2762 final int count = mChildrenCount; 2763 for (int i = 0; i < count; i++) { 2764 children[i].setPressed(pressed); 2765 } 2766 } 2767 2768 /** 2769 * When this property is set to true, this ViewGroup supports static transformations on 2770 * children; this causes 2771 * {@link #getChildStaticTransformation(View, android.view.animation.Transformation)} to be 2772 * invoked when a child is drawn. 2773 * 2774 * Any subclass overriding 2775 * {@link #getChildStaticTransformation(View, android.view.animation.Transformation)} should 2776 * set this property to true. 2777 * 2778 * @param enabled True to enable static transformations on children, false otherwise. 2779 * 2780 * @see #FLAG_SUPPORT_STATIC_TRANSFORMATIONS 2781 */ 2782 protected void setStaticTransformationsEnabled(boolean enabled) { 2783 setBooleanFlag(FLAG_SUPPORT_STATIC_TRANSFORMATIONS, enabled); 2784 } 2785 2786 /** 2787 * Sets <code>t</code> to be the static transformation of the child, if set, returning a 2788 * boolean to indicate whether a static transform was set. The default implementation 2789 * simply returns <code>false</code>; subclasses may override this method for different 2790 * behavior. 2791 * 2792 * @param child The child view whose static transform is being requested 2793 * @param t The Transformation which will hold the result 2794 * @return true if the transformation was set, false otherwise 2795 * @see #setStaticTransformationsEnabled(boolean) 2796 */ 2797 protected boolean getChildStaticTransformation(View child, Transformation t) { 2798 return false; 2799 } 2800 2801 /** 2802 * {@hide} 2803 */ 2804 @Override 2805 protected View findViewTraversal(int id) { 2806 if (id == mID) { 2807 return this; 2808 } 2809 2810 final View[] where = mChildren; 2811 final int len = mChildrenCount; 2812 2813 for (int i = 0; i < len; i++) { 2814 View v = where[i]; 2815 2816 if ((v.mPrivateFlags & IS_ROOT_NAMESPACE) == 0) { 2817 v = v.findViewById(id); 2818 2819 if (v != null) { 2820 return v; 2821 } 2822 } 2823 } 2824 2825 return null; 2826 } 2827 2828 /** 2829 * {@hide} 2830 */ 2831 @Override 2832 protected View findViewWithTagTraversal(Object tag) { 2833 if (tag != null && tag.equals(mTag)) { 2834 return this; 2835 } 2836 2837 final View[] where = mChildren; 2838 final int len = mChildrenCount; 2839 2840 for (int i = 0; i < len; i++) { 2841 View v = where[i]; 2842 2843 if ((v.mPrivateFlags & IS_ROOT_NAMESPACE) == 0) { 2844 v = v.findViewWithTag(tag); 2845 2846 if (v != null) { 2847 return v; 2848 } 2849 } 2850 } 2851 2852 return null; 2853 } 2854 2855 /** 2856 * {@hide} 2857 */ 2858 @Override 2859 protected View findViewByPredicateTraversal(Predicate<View> predicate, View childToSkip) { 2860 if (predicate.apply(this)) { 2861 return this; 2862 } 2863 2864 final View[] where = mChildren; 2865 final int len = mChildrenCount; 2866 2867 for (int i = 0; i < len; i++) { 2868 View v = where[i]; 2869 2870 if (v != childToSkip && (v.mPrivateFlags & IS_ROOT_NAMESPACE) == 0) { 2871 v = v.findViewByPredicate(predicate); 2872 2873 if (v != null) { 2874 return v; 2875 } 2876 } 2877 } 2878 2879 return null; 2880 } 2881 2882 /** 2883 * Adds a child view. If no layout parameters are already set on the child, the 2884 * default parameters for this ViewGroup are set on the child. 2885 * 2886 * @param child the child view to add 2887 * 2888 * @see #generateDefaultLayoutParams() 2889 */ 2890 public void addView(View child) { 2891 addView(child, -1); 2892 } 2893 2894 /** 2895 * Adds a child view. If no layout parameters are already set on the child, the 2896 * default parameters for this ViewGroup are set on the child. 2897 * 2898 * @param child the child view to add 2899 * @param index the position at which to add the child 2900 * 2901 * @see #generateDefaultLayoutParams() 2902 */ 2903 public void addView(View child, int index) { 2904 LayoutParams params = child.getLayoutParams(); 2905 if (params == null) { 2906 params = generateDefaultLayoutParams(); 2907 if (params == null) { 2908 throw new IllegalArgumentException("generateDefaultLayoutParams() cannot return null"); 2909 } 2910 } 2911 addView(child, index, params); 2912 } 2913 2914 /** 2915 * Adds a child view with this ViewGroup's default layout parameters and the 2916 * specified width and height. 2917 * 2918 * @param child the child view to add 2919 */ 2920 public void addView(View child, int width, int height) { 2921 final LayoutParams params = generateDefaultLayoutParams(); 2922 params.width = width; 2923 params.height = height; 2924 addView(child, -1, params); 2925 } 2926 2927 /** 2928 * Adds a child view with the specified layout parameters. 2929 * 2930 * @param child the child view to add 2931 * @param params the layout parameters to set on the child 2932 */ 2933 public void addView(View child, LayoutParams params) { 2934 addView(child, -1, params); 2935 } 2936 2937 /** 2938 * Adds a child view with the specified layout parameters. 2939 * 2940 * @param child the child view to add 2941 * @param index the position at which to add the child 2942 * @param params the layout parameters to set on the child 2943 */ 2944 public void addView(View child, int index, LayoutParams params) { 2945 if (DBG) { 2946 System.out.println(this + " addView"); 2947 } 2948 2949 // addViewInner() will call child.requestLayout() when setting the new LayoutParams 2950 // therefore, we call requestLayout() on ourselves before, so that the child's request 2951 // will be blocked at our level 2952 requestLayout(); 2953 invalidate(true); 2954 addViewInner(child, index, params, false); 2955 } 2956 2957 /** 2958 * {@inheritDoc} 2959 */ 2960 public void updateViewLayout(View view, ViewGroup.LayoutParams params) { 2961 if (!checkLayoutParams(params)) { 2962 throw new IllegalArgumentException("Invalid LayoutParams supplied to " + this); 2963 } 2964 if (view.mParent != this) { 2965 throw new IllegalArgumentException("Given view not a child of " + this); 2966 } 2967 view.setLayoutParams(params); 2968 } 2969 2970 /** 2971 * {@inheritDoc} 2972 */ 2973 protected boolean checkLayoutParams(ViewGroup.LayoutParams p) { 2974 return p != null; 2975 } 2976 2977 /** 2978 * Interface definition for a callback to be invoked when the hierarchy 2979 * within this view changed. The hierarchy changes whenever a child is added 2980 * to or removed from this view. 2981 */ 2982 public interface OnHierarchyChangeListener { 2983 /** 2984 * Called when a new child is added to a parent view. 2985 * 2986 * @param parent the view in which a child was added 2987 * @param child the new child view added in the hierarchy 2988 */ 2989 void onChildViewAdded(View parent, View child); 2990 2991 /** 2992 * Called when a child is removed from a parent view. 2993 * 2994 * @param parent the view from which the child was removed 2995 * @param child the child removed from the hierarchy 2996 */ 2997 void onChildViewRemoved(View parent, View child); 2998 } 2999 3000 /** 3001 * Register a callback to be invoked when a child is added to or removed 3002 * from this view. 3003 * 3004 * @param listener the callback to invoke on hierarchy change 3005 */ 3006 public void setOnHierarchyChangeListener(OnHierarchyChangeListener listener) { 3007 mOnHierarchyChangeListener = listener; 3008 } 3009 3010 /** 3011 * @hide 3012 */ 3013 protected void onViewAdded(View child) { 3014 if (mOnHierarchyChangeListener != null) { 3015 mOnHierarchyChangeListener.onChildViewAdded(this, child); 3016 } 3017 } 3018 3019 /** 3020 * @hide 3021 */ 3022 protected void onViewRemoved(View child) { 3023 if (mOnHierarchyChangeListener != null) { 3024 mOnHierarchyChangeListener.onChildViewRemoved(this, child); 3025 } 3026 } 3027 3028 /** 3029 * Adds a view during layout. This is useful if in your onLayout() method, 3030 * you need to add more views (as does the list view for example). 3031 * 3032 * If index is negative, it means put it at the end of the list. 3033 * 3034 * @param child the view to add to the group 3035 * @param index the index at which the child must be added 3036 * @param params the layout parameters to associate with the child 3037 * @return true if the child was added, false otherwise 3038 */ 3039 protected boolean addViewInLayout(View child, int index, LayoutParams params) { 3040 return addViewInLayout(child, index, params, false); 3041 } 3042 3043 /** 3044 * Adds a view during layout. This is useful if in your onLayout() method, 3045 * you need to add more views (as does the list view for example). 3046 * 3047 * If index is negative, it means put it at the end of the list. 3048 * 3049 * @param child the view to add to the group 3050 * @param index the index at which the child must be added 3051 * @param params the layout parameters to associate with the child 3052 * @param preventRequestLayout if true, calling this method will not trigger a 3053 * layout request on child 3054 * @return true if the child was added, false otherwise 3055 */ 3056 protected boolean addViewInLayout(View child, int index, LayoutParams params, 3057 boolean preventRequestLayout) { 3058 child.mParent = null; 3059 addViewInner(child, index, params, preventRequestLayout); 3060 child.mPrivateFlags = (child.mPrivateFlags & ~DIRTY_MASK) | DRAWN; 3061 return true; 3062 } 3063 3064 /** 3065 * Prevents the specified child to be laid out during the next layout pass. 3066 * 3067 * @param child the child on which to perform the cleanup 3068 */ 3069 protected void cleanupLayoutState(View child) { 3070 child.mPrivateFlags &= ~View.FORCE_LAYOUT; 3071 } 3072 3073 private void addViewInner(View child, int index, LayoutParams params, 3074 boolean preventRequestLayout) { 3075 3076 if (getAccessibilityNodeProvider() != null) { 3077 throw new IllegalStateException("Views with AccessibilityNodeProvider" 3078 + " can't have children."); 3079 } 3080 3081 if (mTransition != null) { 3082 // Don't prevent other add transitions from completing, but cancel remove 3083 // transitions to let them complete the process before we add to the container 3084 mTransition.cancel(LayoutTransition.DISAPPEARING); 3085 } 3086 3087 if (child.getParent() != null) { 3088 throw new IllegalStateException("The specified child already has a parent. " + 3089 "You must call removeView() on the child's parent first."); 3090 } 3091 3092 if (mTransition != null) { 3093 mTransition.addChild(this, child); 3094 } 3095 3096 if (!checkLayoutParams(params)) { 3097 params = generateLayoutParams(params); 3098 } 3099 3100 if (preventRequestLayout) { 3101 child.mLayoutParams = params; 3102 } else { 3103 child.setLayoutParams(params); 3104 } 3105 3106 if (index < 0) { 3107 index = mChildrenCount; 3108 } 3109 3110 addInArray(child, index); 3111 3112 // tell our children 3113 if (preventRequestLayout) { 3114 child.assignParent(this); 3115 } else { 3116 child.mParent = this; 3117 } 3118 3119 if (child.hasFocus()) { 3120 requestChildFocus(child, child.findFocus()); 3121 } 3122 3123 AttachInfo ai = mAttachInfo; 3124 if (ai != null && (mGroupFlags & FLAG_PREVENT_DISPATCH_ATTACHED_TO_WINDOW) == 0) { 3125 boolean lastKeepOn = ai.mKeepScreenOn; 3126 ai.mKeepScreenOn = false; 3127 child.dispatchAttachedToWindow(mAttachInfo, (mViewFlags&VISIBILITY_MASK)); 3128 if (ai.mKeepScreenOn) { 3129 needGlobalAttributesUpdate(true); 3130 } 3131 ai.mKeepScreenOn = lastKeepOn; 3132 } 3133 3134 onViewAdded(child); 3135 3136 if ((child.mViewFlags & DUPLICATE_PARENT_STATE) == DUPLICATE_PARENT_STATE) { 3137 mGroupFlags |= FLAG_NOTIFY_CHILDREN_ON_DRAWABLE_STATE_CHANGE; 3138 } 3139 3140 if (child.hasTransientState()) { 3141 childHasTransientStateChanged(child, true); 3142 } 3143 } 3144 3145 private void addInArray(View child, int index) { 3146 View[] children = mChildren; 3147 final int count = mChildrenCount; 3148 final int size = children.length; 3149 if (index == count) { 3150 if (size == count) { 3151 mChildren = new View[size + ARRAY_CAPACITY_INCREMENT]; 3152 System.arraycopy(children, 0, mChildren, 0, size); 3153 children = mChildren; 3154 } 3155 children[mChildrenCount++] = child; 3156 } else if (index < count) { 3157 if (size == count) { 3158 mChildren = new View[size + ARRAY_CAPACITY_INCREMENT]; 3159 System.arraycopy(children, 0, mChildren, 0, index); 3160 System.arraycopy(children, index, mChildren, index + 1, count - index); 3161 children = mChildren; 3162 } else { 3163 System.arraycopy(children, index, children, index + 1, count - index); 3164 } 3165 children[index] = child; 3166 mChildrenCount++; 3167 if (mLastTouchDownIndex >= index) { 3168 mLastTouchDownIndex++; 3169 } 3170 } else { 3171 throw new IndexOutOfBoundsException("index=" + index + " count=" + count); 3172 } 3173 } 3174 3175 // This method also sets the child's mParent to null 3176 private void removeFromArray(int index) { 3177 final View[] children = mChildren; 3178 if (!(mTransitioningViews != null && mTransitioningViews.contains(children[index]))) { 3179 children[index].mParent = null; 3180 } 3181 final int count = mChildrenCount; 3182 if (index == count - 1) { 3183 children[--mChildrenCount] = null; 3184 } else if (index >= 0 && index < count) { 3185 System.arraycopy(children, index + 1, children, index, count - index - 1); 3186 children[--mChildrenCount] = null; 3187 } else { 3188 throw new IndexOutOfBoundsException(); 3189 } 3190 if (mLastTouchDownIndex == index) { 3191 mLastTouchDownTime = 0; 3192 mLastTouchDownIndex = -1; 3193 } else if (mLastTouchDownIndex > index) { 3194 mLastTouchDownIndex--; 3195 } 3196 } 3197 3198 // This method also sets the children's mParent to null 3199 private void removeFromArray(int start, int count) { 3200 final View[] children = mChildren; 3201 final int childrenCount = mChildrenCount; 3202 3203 start = Math.max(0, start); 3204 final int end = Math.min(childrenCount, start + count); 3205 3206 if (start == end) { 3207 return; 3208 } 3209 3210 if (end == childrenCount) { 3211 for (int i = start; i < end; i++) { 3212 children[i].mParent = null; 3213 children[i] = null; 3214 } 3215 } else { 3216 for (int i = start; i < end; i++) { 3217 children[i].mParent = null; 3218 } 3219 3220 // Since we're looping above, we might as well do the copy, but is arraycopy() 3221 // faster than the extra 2 bounds checks we would do in the loop? 3222 System.arraycopy(children, end, children, start, childrenCount - end); 3223 3224 for (int i = childrenCount - (end - start); i < childrenCount; i++) { 3225 children[i] = null; 3226 } 3227 } 3228 3229 mChildrenCount -= (end - start); 3230 } 3231 3232 private void bindLayoutAnimation(View child) { 3233 Animation a = mLayoutAnimationController.getAnimationForView(child); 3234 child.setAnimation(a); 3235 } 3236 3237 /** 3238 * Subclasses should override this method to set layout animation 3239 * parameters on the supplied child. 3240 * 3241 * @param child the child to associate with animation parameters 3242 * @param params the child's layout parameters which hold the animation 3243 * parameters 3244 * @param index the index of the child in the view group 3245 * @param count the number of children in the view group 3246 */ 3247 protected void attachLayoutAnimationParameters(View child, 3248 LayoutParams params, int index, int count) { 3249 LayoutAnimationController.AnimationParameters animationParams = 3250 params.layoutAnimationParameters; 3251 if (animationParams == null) { 3252 animationParams = new LayoutAnimationController.AnimationParameters(); 3253 params.layoutAnimationParameters = animationParams; 3254 } 3255 3256 animationParams.count = count; 3257 animationParams.index = index; 3258 } 3259 3260 /** 3261 * {@inheritDoc} 3262 */ 3263 public void removeView(View view) { 3264 removeViewInternal(view); 3265 requestLayout(); 3266 invalidate(true); 3267 } 3268 3269 /** 3270 * Removes a view during layout. This is useful if in your onLayout() method, 3271 * you need to remove more views. 3272 * 3273 * @param view the view to remove from the group 3274 */ 3275 public void removeViewInLayout(View view) { 3276 removeViewInternal(view); 3277 } 3278 3279 /** 3280 * Removes a range of views during layout. This is useful if in your onLayout() method, 3281 * you need to remove more views. 3282 * 3283 * @param start the index of the first view to remove from the group 3284 * @param count the number of views to remove from the group 3285 */ 3286 public void removeViewsInLayout(int start, int count) { 3287 removeViewsInternal(start, count); 3288 } 3289 3290 /** 3291 * Removes the view at the specified position in the group. 3292 * 3293 * @param index the position in the group of the view to remove 3294 */ 3295 public void removeViewAt(int index) { 3296 removeViewInternal(index, getChildAt(index)); 3297 requestLayout(); 3298 invalidate(true); 3299 } 3300 3301 /** 3302 * Removes the specified range of views from the group. 3303 * 3304 * @param start the first position in the group of the range of views to remove 3305 * @param count the number of views to remove 3306 */ 3307 public void removeViews(int start, int count) { 3308 removeViewsInternal(start, count); 3309 requestLayout(); 3310 invalidate(true); 3311 } 3312 3313 private void removeViewInternal(View view) { 3314 final int index = indexOfChild(view); 3315 if (index >= 0) { 3316 removeViewInternal(index, view); 3317 } 3318 } 3319 3320 private void removeViewInternal(int index, View view) { 3321 3322 if (mTransition != null) { 3323 mTransition.removeChild(this, view); 3324 } 3325 3326 boolean clearChildFocus = false; 3327 if (view == mFocused) { 3328 view.clearFocusForRemoval(); 3329 clearChildFocus = true; 3330 } 3331 3332 if (view.getAnimation() != null || 3333 (mTransitioningViews != null && mTransitioningViews.contains(view))) { 3334 addDisappearingView(view); 3335 } else if (view.mAttachInfo != null) { 3336 view.dispatchDetachedFromWindow(); 3337 } 3338 3339 if (view.hasTransientState()) { 3340 childHasTransientStateChanged(view, false); 3341 } 3342 3343 onViewRemoved(view); 3344 3345 needGlobalAttributesUpdate(false); 3346 3347 removeFromArray(index); 3348 3349 if (clearChildFocus) { 3350 clearChildFocus(view); 3351 } 3352 } 3353 3354 /** 3355 * Sets the LayoutTransition object for this ViewGroup. If the LayoutTransition object is 3356 * not null, changes in layout which occur because of children being added to or removed from 3357 * the ViewGroup will be animated according to the animations defined in that LayoutTransition 3358 * object. By default, the transition object is null (so layout changes are not animated). 3359 * 3360 * @param transition The LayoutTransition object that will animated changes in layout. A value 3361 * of <code>null</code> means no transition will run on layout changes. 3362 * @attr ref android.R.styleable#ViewGroup_animateLayoutChanges 3363 */ 3364 public void setLayoutTransition(LayoutTransition transition) { 3365 if (mTransition != null) { 3366 mTransition.removeTransitionListener(mLayoutTransitionListener); 3367 } 3368 mTransition = transition; 3369 if (mTransition != null) { 3370 mTransition.addTransitionListener(mLayoutTransitionListener); 3371 } 3372 } 3373 3374 /** 3375 * Gets the LayoutTransition object for this ViewGroup. If the LayoutTransition object is 3376 * not null, changes in layout which occur because of children being added to or removed from 3377 * the ViewGroup will be animated according to the animations defined in that LayoutTransition 3378 * object. By default, the transition object is null (so layout changes are not animated). 3379 * 3380 * @return LayoutTranstion The LayoutTransition object that will animated changes in layout. 3381 * A value of <code>null</code> means no transition will run on layout changes. 3382 */ 3383 public LayoutTransition getLayoutTransition() { 3384 return mTransition; 3385 } 3386 3387 private void removeViewsInternal(int start, int count) { 3388 final View focused = mFocused; 3389 final boolean detach = mAttachInfo != null; 3390 View clearChildFocus = null; 3391 3392 final View[] children = mChildren; 3393 final int end = start + count; 3394 3395 for (int i = start; i < end; i++) { 3396 final View view = children[i]; 3397 3398 if (mTransition != null) { 3399 mTransition.removeChild(this, view); 3400 } 3401 3402 if (view == focused) { 3403 view.clearFocusForRemoval(); 3404 clearChildFocus = view; 3405 } 3406 3407 if (view.getAnimation() != null || 3408 (mTransitioningViews != null && mTransitioningViews.contains(view))) { 3409 addDisappearingView(view); 3410 } else if (detach) { 3411 view.dispatchDetachedFromWindow(); 3412 } 3413 3414 if (view.hasTransientState()) { 3415 childHasTransientStateChanged(view, false); 3416 } 3417 3418 needGlobalAttributesUpdate(false); 3419 3420 onViewRemoved(view); 3421 } 3422 3423 removeFromArray(start, count); 3424 3425 if (clearChildFocus != null) { 3426 clearChildFocus(clearChildFocus); 3427 } 3428 } 3429 3430 /** 3431 * Call this method to remove all child views from the 3432 * ViewGroup. 3433 */ 3434 public void removeAllViews() { 3435 removeAllViewsInLayout(); 3436 requestLayout(); 3437 invalidate(true); 3438 } 3439 3440 /** 3441 * Called by a ViewGroup subclass to remove child views from itself, 3442 * when it must first know its size on screen before it can calculate how many 3443 * child views it will render. An example is a Gallery or a ListView, which 3444 * may "have" 50 children, but actually only render the number of children 3445 * that can currently fit inside the object on screen. Do not call 3446 * this method unless you are extending ViewGroup and understand the 3447 * view measuring and layout pipeline. 3448 */ 3449 public void removeAllViewsInLayout() { 3450 final int count = mChildrenCount; 3451 if (count <= 0) { 3452 return; 3453 } 3454 3455 final View[] children = mChildren; 3456 mChildrenCount = 0; 3457 3458 final View focused = mFocused; 3459 final boolean detach = mAttachInfo != null; 3460 View clearChildFocus = null; 3461 3462 needGlobalAttributesUpdate(false); 3463 3464 for (int i = count - 1; i >= 0; i--) { 3465 final View view = children[i]; 3466 3467 if (mTransition != null) { 3468 mTransition.removeChild(this, view); 3469 } 3470 3471 if (view == focused) { 3472 view.clearFocusForRemoval(); 3473 clearChildFocus = view; 3474 } 3475 3476 if (view.getAnimation() != null || 3477 (mTransitioningViews != null && mTransitioningViews.contains(view))) { 3478 addDisappearingView(view); 3479 } else if (detach) { 3480 view.dispatchDetachedFromWindow(); 3481 } 3482 3483 if (view.hasTransientState()) { 3484 childHasTransientStateChanged(view, false); 3485 } 3486 3487 onViewRemoved(view); 3488 3489 view.mParent = null; 3490 children[i] = null; 3491 } 3492 3493 if (clearChildFocus != null) { 3494 clearChildFocus(clearChildFocus); 3495 } 3496 } 3497 3498 /** 3499 * Finishes the removal of a detached view. This method will dispatch the detached from 3500 * window event and notify the hierarchy change listener. 3501 * 3502 * @param child the child to be definitely removed from the view hierarchy 3503 * @param animate if true and the view has an animation, the view is placed in the 3504 * disappearing views list, otherwise, it is detached from the window 3505 * 3506 * @see #attachViewToParent(View, int, android.view.ViewGroup.LayoutParams) 3507 * @see #detachAllViewsFromParent() 3508 * @see #detachViewFromParent(View) 3509 * @see #detachViewFromParent(int) 3510 */ 3511 protected void removeDetachedView(View child, boolean animate) { 3512 if (mTransition != null) { 3513 mTransition.removeChild(this, child); 3514 } 3515 3516 if (child == mFocused) { 3517 child.clearFocus(); 3518 } 3519 3520 if ((animate && child.getAnimation() != null) || 3521 (mTransitioningViews != null && mTransitioningViews.contains(child))) { 3522 addDisappearingView(child); 3523 } else if (child.mAttachInfo != null) { 3524 child.dispatchDetachedFromWindow(); 3525 } 3526 3527 if (child.hasTransientState()) { 3528 childHasTransientStateChanged(child, false); 3529 } 3530 3531 onViewRemoved(child); 3532 } 3533 3534 /** 3535 * Attaches a view to this view group. Attaching a view assigns this group as the parent, 3536 * sets the layout parameters and puts the view in the list of children so it can be retrieved 3537 * by calling {@link #getChildAt(int)}. 3538 * 3539 * This method should be called only for view which were detached from their parent. 3540 * 3541 * @param child the child to attach 3542 * @param index the index at which the child should be attached 3543 * @param params the layout parameters of the child 3544 * 3545 * @see #removeDetachedView(View, boolean) 3546 * @see #detachAllViewsFromParent() 3547 * @see #detachViewFromParent(View) 3548 * @see #detachViewFromParent(int) 3549 */ 3550 protected void attachViewToParent(View child, int index, LayoutParams params) { 3551 child.mLayoutParams = params; 3552 3553 if (index < 0) { 3554 index = mChildrenCount; 3555 } 3556 3557 addInArray(child, index); 3558 3559 child.mParent = this; 3560 child.mPrivateFlags = (child.mPrivateFlags & ~DIRTY_MASK & ~DRAWING_CACHE_VALID) | 3561 DRAWN | INVALIDATED; 3562 this.mPrivateFlags |= INVALIDATED; 3563 3564 if (child.hasFocus()) { 3565 requestChildFocus(child, child.findFocus()); 3566 } 3567 } 3568 3569 /** 3570 * Detaches a view from its parent. Detaching a view should be temporary and followed 3571 * either by a call to {@link #attachViewToParent(View, int, android.view.ViewGroup.LayoutParams)} 3572 * or a call to {@link #removeDetachedView(View, boolean)}. When a view is detached, 3573 * its parent is null and cannot be retrieved by a call to {@link #getChildAt(int)}. 3574 * 3575 * @param child the child to detach 3576 * 3577 * @see #detachViewFromParent(int) 3578 * @see #detachViewsFromParent(int, int) 3579 * @see #detachAllViewsFromParent() 3580 * @see #attachViewToParent(View, int, android.view.ViewGroup.LayoutParams) 3581 * @see #removeDetachedView(View, boolean) 3582 */ 3583 protected void detachViewFromParent(View child) { 3584 removeFromArray(indexOfChild(child)); 3585 } 3586 3587 /** 3588 * Detaches a view from its parent. Detaching a view should be temporary and followed 3589 * either by a call to {@link #attachViewToParent(View, int, android.view.ViewGroup.LayoutParams)} 3590 * or a call to {@link #removeDetachedView(View, boolean)}. When a view is detached, 3591 * its parent is null and cannot be retrieved by a call to {@link #getChildAt(int)}. 3592 * 3593 * @param index the index of the child to detach 3594 * 3595 * @see #detachViewFromParent(View) 3596 * @see #detachAllViewsFromParent() 3597 * @see #detachViewsFromParent(int, int) 3598 * @see #attachViewToParent(View, int, android.view.ViewGroup.LayoutParams) 3599 * @see #removeDetachedView(View, boolean) 3600 */ 3601 protected void detachViewFromParent(int index) { 3602 removeFromArray(index); 3603 } 3604 3605 /** 3606 * Detaches a range of view from their parent. Detaching a view should be temporary and followed 3607 * either by a call to {@link #attachViewToParent(View, int, android.view.ViewGroup.LayoutParams)} 3608 * or a call to {@link #removeDetachedView(View, boolean)}. When a view is detached, its 3609 * parent is null and cannot be retrieved by a call to {@link #getChildAt(int)}. 3610 * 3611 * @param start the first index of the childrend range to detach 3612 * @param count the number of children to detach 3613 * 3614 * @see #detachViewFromParent(View) 3615 * @see #detachViewFromParent(int) 3616 * @see #detachAllViewsFromParent() 3617 * @see #attachViewToParent(View, int, android.view.ViewGroup.LayoutParams) 3618 * @see #removeDetachedView(View, boolean) 3619 */ 3620 protected void detachViewsFromParent(int start, int count) { 3621 removeFromArray(start, count); 3622 } 3623 3624 /** 3625 * Detaches all views from the parent. Detaching a view should be temporary and followed 3626 * either by a call to {@link #attachViewToParent(View, int, android.view.ViewGroup.LayoutParams)} 3627 * or a call to {@link #removeDetachedView(View, boolean)}. When a view is detached, 3628 * its parent is null and cannot be retrieved by a call to {@link #getChildAt(int)}. 3629 * 3630 * @see #detachViewFromParent(View) 3631 * @see #detachViewFromParent(int) 3632 * @see #detachViewsFromParent(int, int) 3633 * @see #attachViewToParent(View, int, android.view.ViewGroup.LayoutParams) 3634 * @see #removeDetachedView(View, boolean) 3635 */ 3636 protected void detachAllViewsFromParent() { 3637 final int count = mChildrenCount; 3638 if (count <= 0) { 3639 return; 3640 } 3641 3642 final View[] children = mChildren; 3643 mChildrenCount = 0; 3644 3645 for (int i = count - 1; i >= 0; i--) { 3646 children[i].mParent = null; 3647 children[i] = null; 3648 } 3649 } 3650 3651 /** 3652 * Don't call or override this method. It is used for the implementation of 3653 * the view hierarchy. 3654 */ 3655 public final void invalidateChild(View child, final Rect dirty) { 3656 if (ViewDebug.TRACE_HIERARCHY) { 3657 ViewDebug.trace(this, ViewDebug.HierarchyTraceType.INVALIDATE_CHILD); 3658 } 3659 3660 ViewParent parent = this; 3661 3662 final AttachInfo attachInfo = mAttachInfo; 3663 if (attachInfo != null) { 3664 // If the child is drawing an animation, we want to copy this flag onto 3665 // ourselves and the parent to make sure the invalidate request goes 3666 // through 3667 final boolean drawAnimation = (child.mPrivateFlags & DRAW_ANIMATION) == DRAW_ANIMATION; 3668 3669 //noinspection PointlessBooleanExpression 3670 if (!HardwareRenderer.RENDER_DIRTY_REGIONS) { 3671 if (dirty == null) { 3672 if (child.mLayerType != LAYER_TYPE_NONE) { 3673 mPrivateFlags |= INVALIDATED; 3674 mPrivateFlags &= ~DRAWING_CACHE_VALID; 3675 child.mLocalDirtyRect.setEmpty(); 3676 } 3677 do { 3678 View view = null; 3679 if (parent instanceof View) { 3680 view = (View) parent; 3681 if (view.mLayerType != LAYER_TYPE_NONE) { 3682 view.mLocalDirtyRect.setEmpty(); 3683 if (view.getParent() instanceof View) { 3684 final View grandParent = (View) view.getParent(); 3685 grandParent.mPrivateFlags |= INVALIDATED; 3686 grandParent.mPrivateFlags &= ~DRAWING_CACHE_VALID; 3687 } 3688 } 3689 if ((view.mPrivateFlags & DIRTY_MASK) != 0) { 3690 // already marked dirty - we're done 3691 break; 3692 } 3693 } 3694 3695 if (drawAnimation) { 3696 if (view != null) { 3697 view.mPrivateFlags |= DRAW_ANIMATION; 3698 } else if (parent instanceof ViewRootImpl) { 3699 ((ViewRootImpl) parent).mIsAnimating = true; 3700 } 3701 } 3702 3703 if (parent instanceof ViewRootImpl) { 3704 ((ViewRootImpl) parent).invalidate(); 3705 parent = null; 3706 } else if (view != null) { 3707 if ((view.mPrivateFlags & DRAWN) == DRAWN || 3708 (view.mPrivateFlags & DRAWING_CACHE_VALID) == DRAWING_CACHE_VALID) { 3709 view.mPrivateFlags &= ~DRAWING_CACHE_VALID; 3710 view.mPrivateFlags |= DIRTY; 3711 parent = view.mParent; 3712 } else { 3713 parent = null; 3714 } 3715 } 3716 } while (parent != null); 3717 } 3718 3719 return; 3720 } 3721 3722 // Check whether the child that requests the invalidate is fully opaque 3723 // Views being animated or transformed are not considered opaque because we may 3724 // be invalidating their old position and need the parent to paint behind them. 3725 Matrix childMatrix = child.getMatrix(); 3726 final boolean isOpaque = child.isOpaque() && !drawAnimation && 3727 child.getAnimation() == null && childMatrix.isIdentity(); 3728 // Mark the child as dirty, using the appropriate flag 3729 // Make sure we do not set both flags at the same time 3730 int opaqueFlag = isOpaque ? DIRTY_OPAQUE : DIRTY; 3731 3732 if (child.mLayerType != LAYER_TYPE_NONE) { 3733 mPrivateFlags |= INVALIDATED; 3734 mPrivateFlags &= ~DRAWING_CACHE_VALID; 3735 child.mLocalDirtyRect.union(dirty); 3736 } 3737 3738 final int[] location = attachInfo.mInvalidateChildLocation; 3739 location[CHILD_LEFT_INDEX] = child.mLeft; 3740 location[CHILD_TOP_INDEX] = child.mTop; 3741 if (!childMatrix.isIdentity()) { 3742 RectF boundingRect = attachInfo.mTmpTransformRect; 3743 boundingRect.set(dirty); 3744 //boundingRect.inset(-0.5f, -0.5f); 3745 childMatrix.mapRect(boundingRect); 3746 dirty.set((int) (boundingRect.left - 0.5f), 3747 (int) (boundingRect.top - 0.5f), 3748 (int) (boundingRect.right + 0.5f), 3749 (int) (boundingRect.bottom + 0.5f)); 3750 } 3751 3752 do { 3753 View view = null; 3754 if (parent instanceof View) { 3755 view = (View) parent; 3756 if (view.mLayerType != LAYER_TYPE_NONE && 3757 view.getParent() instanceof View) { 3758 final View grandParent = (View) view.getParent(); 3759 grandParent.mPrivateFlags |= INVALIDATED; 3760 grandParent.mPrivateFlags &= ~DRAWING_CACHE_VALID; 3761 } 3762 } 3763 3764 if (drawAnimation) { 3765 if (view != null) { 3766 view.mPrivateFlags |= DRAW_ANIMATION; 3767 } else if (parent instanceof ViewRootImpl) { 3768 ((ViewRootImpl) parent).mIsAnimating = true; 3769 } 3770 } 3771 3772 // If the parent is dirty opaque or not dirty, mark it dirty with the opaque 3773 // flag coming from the child that initiated the invalidate 3774 if (view != null) { 3775 if ((view.mViewFlags & FADING_EDGE_MASK) != 0 && 3776 view.getSolidColor() == 0) { 3777 opaqueFlag = DIRTY; 3778 } 3779 if ((view.mPrivateFlags & DIRTY_MASK) != DIRTY) { 3780 view.mPrivateFlags = (view.mPrivateFlags & ~DIRTY_MASK) | opaqueFlag; 3781 } 3782 } 3783 3784 parent = parent.invalidateChildInParent(location, dirty); 3785 if (view != null) { 3786 // Account for transform on current parent 3787 Matrix m = view.getMatrix(); 3788 if (!m.isIdentity()) { 3789 RectF boundingRect = attachInfo.mTmpTransformRect; 3790 boundingRect.set(dirty); 3791 m.mapRect(boundingRect); 3792 dirty.set((int) (boundingRect.left - 0.5f), 3793 (int) (boundingRect.top - 0.5f), 3794 (int) (boundingRect.right + 0.5f), 3795 (int) (boundingRect.bottom + 0.5f)); 3796 } 3797 } 3798 } while (parent != null); 3799 } 3800 } 3801 3802 /** 3803 * Don't call or override this method. It is used for the implementation of 3804 * the view hierarchy. 3805 * 3806 * This implementation returns null if this ViewGroup does not have a parent, 3807 * if this ViewGroup is already fully invalidated or if the dirty rectangle 3808 * does not intersect with this ViewGroup's bounds. 3809 */ 3810 public ViewParent invalidateChildInParent(final int[] location, final Rect dirty) { 3811 if (ViewDebug.TRACE_HIERARCHY) { 3812 ViewDebug.trace(this, ViewDebug.HierarchyTraceType.INVALIDATE_CHILD_IN_PARENT); 3813 } 3814 3815 if ((mPrivateFlags & DRAWN) == DRAWN || 3816 (mPrivateFlags & DRAWING_CACHE_VALID) == DRAWING_CACHE_VALID) { 3817 if ((mGroupFlags & (FLAG_OPTIMIZE_INVALIDATE | FLAG_ANIMATION_DONE)) != 3818 FLAG_OPTIMIZE_INVALIDATE) { 3819 dirty.offset(location[CHILD_LEFT_INDEX] - mScrollX, 3820 location[CHILD_TOP_INDEX] - mScrollY); 3821 3822 final int left = mLeft; 3823 final int top = mTop; 3824 3825 if ((mGroupFlags & FLAG_CLIP_CHILDREN) != FLAG_CLIP_CHILDREN || 3826 dirty.intersect(0, 0, mRight - left, mBottom - top) || 3827 (mPrivateFlags & DRAW_ANIMATION) == DRAW_ANIMATION) { 3828 mPrivateFlags &= ~DRAWING_CACHE_VALID; 3829 3830 location[CHILD_LEFT_INDEX] = left; 3831 location[CHILD_TOP_INDEX] = top; 3832 3833 if (mLayerType != LAYER_TYPE_NONE) { 3834 mLocalDirtyRect.union(dirty); 3835 } 3836 3837 return mParent; 3838 } 3839 } else { 3840 mPrivateFlags &= ~DRAWN & ~DRAWING_CACHE_VALID; 3841 3842 location[CHILD_LEFT_INDEX] = mLeft; 3843 location[CHILD_TOP_INDEX] = mTop; 3844 if ((mGroupFlags & FLAG_CLIP_CHILDREN) == FLAG_CLIP_CHILDREN) { 3845 dirty.set(0, 0, mRight - mLeft, mBottom - mTop); 3846 } else { 3847 // in case the dirty rect extends outside the bounds of this container 3848 dirty.union(0, 0, mRight - mLeft, mBottom - mTop); 3849 } 3850 3851 if (mLayerType != LAYER_TYPE_NONE) { 3852 mLocalDirtyRect.union(dirty); 3853 } 3854 3855 return mParent; 3856 } 3857 } 3858 3859 return null; 3860 } 3861 3862 /** 3863 * Offset a rectangle that is in a descendant's coordinate 3864 * space into our coordinate space. 3865 * @param descendant A descendant of this view 3866 * @param rect A rectangle defined in descendant's coordinate space. 3867 */ 3868 public final void offsetDescendantRectToMyCoords(View descendant, Rect rect) { 3869 offsetRectBetweenParentAndChild(descendant, rect, true, false); 3870 } 3871 3872 /** 3873 * Offset a rectangle that is in our coordinate space into an ancestor's 3874 * coordinate space. 3875 * @param descendant A descendant of this view 3876 * @param rect A rectangle defined in descendant's coordinate space. 3877 */ 3878 public final void offsetRectIntoDescendantCoords(View descendant, Rect rect) { 3879 offsetRectBetweenParentAndChild(descendant, rect, false, false); 3880 } 3881 3882 /** 3883 * Helper method that offsets a rect either from parent to descendant or 3884 * descendant to parent. 3885 */ 3886 void offsetRectBetweenParentAndChild(View descendant, Rect rect, 3887 boolean offsetFromChildToParent, boolean clipToBounds) { 3888 3889 // already in the same coord system :) 3890 if (descendant == this) { 3891 return; 3892 } 3893 3894 ViewParent theParent = descendant.mParent; 3895 3896 // search and offset up to the parent 3897 while ((theParent != null) 3898 && (theParent instanceof View) 3899 && (theParent != this)) { 3900 3901 if (offsetFromChildToParent) { 3902 rect.offset(descendant.mLeft - descendant.mScrollX, 3903 descendant.mTop - descendant.mScrollY); 3904 if (clipToBounds) { 3905 View p = (View) theParent; 3906 rect.intersect(0, 0, p.mRight - p.mLeft, p.mBottom - p.mTop); 3907 } 3908 } else { 3909 if (clipToBounds) { 3910 View p = (View) theParent; 3911 rect.intersect(0, 0, p.mRight - p.mLeft, p.mBottom - p.mTop); 3912 } 3913 rect.offset(descendant.mScrollX - descendant.mLeft, 3914 descendant.mScrollY - descendant.mTop); 3915 } 3916 3917 descendant = (View) theParent; 3918 theParent = descendant.mParent; 3919 } 3920 3921 // now that we are up to this view, need to offset one more time 3922 // to get into our coordinate space 3923 if (theParent == this) { 3924 if (offsetFromChildToParent) { 3925 rect.offset(descendant.mLeft - descendant.mScrollX, 3926 descendant.mTop - descendant.mScrollY); 3927 } else { 3928 rect.offset(descendant.mScrollX - descendant.mLeft, 3929 descendant.mScrollY - descendant.mTop); 3930 } 3931 } else { 3932 throw new IllegalArgumentException("parameter must be a descendant of this view"); 3933 } 3934 } 3935 3936 /** 3937 * Offset the vertical location of all children of this view by the specified number of pixels. 3938 * 3939 * @param offset the number of pixels to offset 3940 * 3941 * @hide 3942 */ 3943 public void offsetChildrenTopAndBottom(int offset) { 3944 final int count = mChildrenCount; 3945 final View[] children = mChildren; 3946 3947 for (int i = 0; i < count; i++) { 3948 final View v = children[i]; 3949 v.mTop += offset; 3950 v.mBottom += offset; 3951 } 3952 } 3953 3954 /** 3955 * {@inheritDoc} 3956 */ 3957 public boolean getChildVisibleRect(View child, Rect r, android.graphics.Point offset) { 3958 // It doesn't make a whole lot of sense to call this on a view that isn't attached, 3959 // but for some simple tests it can be useful. If we don't have attach info this 3960 // will allocate memory. 3961 final RectF rect = mAttachInfo != null ? mAttachInfo.mTmpTransformRect : new RectF(); 3962 rect.set(r); 3963 3964 if (!child.hasIdentityMatrix()) { 3965 child.getMatrix().mapRect(rect); 3966 } 3967 3968 int dx = child.mLeft - mScrollX; 3969 int dy = child.mTop - mScrollY; 3970 3971 rect.offset(dx, dy); 3972 3973 if (offset != null) { 3974 if (!child.hasIdentityMatrix()) { 3975 float[] position = mAttachInfo != null ? mAttachInfo.mTmpTransformLocation 3976 : new float[2]; 3977 position[0] = offset.x; 3978 position[1] = offset.y; 3979 child.getMatrix().mapPoints(position); 3980 offset.x = (int) (position[0] + 0.5f); 3981 offset.y = (int) (position[1] + 0.5f); 3982 } 3983 offset.x += dx; 3984 offset.y += dy; 3985 } 3986 3987 if (rect.intersect(0, 0, mRight - mLeft, mBottom - mTop)) { 3988 if (mParent == null) return true; 3989 r.set((int) (rect.left + 0.5f), (int) (rect.top + 0.5f), 3990 (int) (rect.right + 0.5f), (int) (rect.bottom + 0.5f)); 3991 return mParent.getChildVisibleRect(this, r, offset); 3992 } 3993 3994 return false; 3995 } 3996 3997 /** 3998 * {@inheritDoc} 3999 */ 4000 @Override 4001 public final void layout(int l, int t, int r, int b) { 4002 if (mTransition == null || !mTransition.isChangingLayout()) { 4003 super.layout(l, t, r, b); 4004 } else { 4005 // record the fact that we noop'd it; request layout when transition finishes 4006 mLayoutSuppressed = true; 4007 } 4008 } 4009 4010 /** 4011 * {@inheritDoc} 4012 */ 4013 @Override 4014 protected abstract void onLayout(boolean changed, 4015 int l, int t, int r, int b); 4016 4017 /** 4018 * Indicates whether the view group has the ability to animate its children 4019 * after the first layout. 4020 * 4021 * @return true if the children can be animated, false otherwise 4022 */ 4023 protected boolean canAnimate() { 4024 return mLayoutAnimationController != null; 4025 } 4026 4027 /** 4028 * Runs the layout animation. Calling this method triggers a relayout of 4029 * this view group. 4030 */ 4031 public void startLayoutAnimation() { 4032 if (mLayoutAnimationController != null) { 4033 mGroupFlags |= FLAG_RUN_ANIMATION; 4034 requestLayout(); 4035 } 4036 } 4037 4038 /** 4039 * Schedules the layout animation to be played after the next layout pass 4040 * of this view group. This can be used to restart the layout animation 4041 * when the content of the view group changes or when the activity is 4042 * paused and resumed. 4043 */ 4044 public void scheduleLayoutAnimation() { 4045 mGroupFlags |= FLAG_RUN_ANIMATION; 4046 } 4047 4048 /** 4049 * Sets the layout animation controller used to animate the group's 4050 * children after the first layout. 4051 * 4052 * @param controller the animation controller 4053 */ 4054 public void setLayoutAnimation(LayoutAnimationController controller) { 4055 mLayoutAnimationController = controller; 4056 if (mLayoutAnimationController != null) { 4057 mGroupFlags |= FLAG_RUN_ANIMATION; 4058 } 4059 } 4060 4061 /** 4062 * Returns the layout animation controller used to animate the group's 4063 * children. 4064 * 4065 * @return the current animation controller 4066 */ 4067 public LayoutAnimationController getLayoutAnimation() { 4068 return mLayoutAnimationController; 4069 } 4070 4071 /** 4072 * Indicates whether the children's drawing cache is used during a layout 4073 * animation. By default, the drawing cache is enabled but this will prevent 4074 * nested layout animations from working. To nest animations, you must disable 4075 * the cache. 4076 * 4077 * @return true if the animation cache is enabled, false otherwise 4078 * 4079 * @see #setAnimationCacheEnabled(boolean) 4080 * @see View#setDrawingCacheEnabled(boolean) 4081 */ 4082 @ViewDebug.ExportedProperty 4083 public boolean isAnimationCacheEnabled() { 4084 return (mGroupFlags & FLAG_ANIMATION_CACHE) == FLAG_ANIMATION_CACHE; 4085 } 4086 4087 /** 4088 * Enables or disables the children's drawing cache during a layout animation. 4089 * By default, the drawing cache is enabled but this will prevent nested 4090 * layout animations from working. To nest animations, you must disable the 4091 * cache. 4092 * 4093 * @param enabled true to enable the animation cache, false otherwise 4094 * 4095 * @see #isAnimationCacheEnabled() 4096 * @see View#setDrawingCacheEnabled(boolean) 4097 */ 4098 public void setAnimationCacheEnabled(boolean enabled) { 4099 setBooleanFlag(FLAG_ANIMATION_CACHE, enabled); 4100 } 4101 4102 /** 4103 * Indicates whether this ViewGroup will always try to draw its children using their 4104 * drawing cache. By default this property is enabled. 4105 * 4106 * @return true if the animation cache is enabled, false otherwise 4107 * 4108 * @see #setAlwaysDrawnWithCacheEnabled(boolean) 4109 * @see #setChildrenDrawnWithCacheEnabled(boolean) 4110 * @see View#setDrawingCacheEnabled(boolean) 4111 */ 4112 @ViewDebug.ExportedProperty(category = "drawing") 4113 public boolean isAlwaysDrawnWithCacheEnabled() { 4114 return (mGroupFlags & FLAG_ALWAYS_DRAWN_WITH_CACHE) == FLAG_ALWAYS_DRAWN_WITH_CACHE; 4115 } 4116 4117 /** 4118 * Indicates whether this ViewGroup will always try to draw its children using their 4119 * drawing cache. This property can be set to true when the cache rendering is 4120 * slightly different from the children's normal rendering. Renderings can be different, 4121 * for instance, when the cache's quality is set to low. 4122 * 4123 * When this property is disabled, the ViewGroup will use the drawing cache of its 4124 * children only when asked to. It's usually the task of subclasses to tell ViewGroup 4125 * when to start using the drawing cache and when to stop using it. 4126 * 4127 * @param always true to always draw with the drawing cache, false otherwise 4128 * 4129 * @see #isAlwaysDrawnWithCacheEnabled() 4130 * @see #setChildrenDrawnWithCacheEnabled(boolean) 4131 * @see View#setDrawingCacheEnabled(boolean) 4132 * @see View#setDrawingCacheQuality(int) 4133 */ 4134 public void setAlwaysDrawnWithCacheEnabled(boolean always) { 4135 setBooleanFlag(FLAG_ALWAYS_DRAWN_WITH_CACHE, always); 4136 } 4137 4138 /** 4139 * Indicates whether the ViewGroup is currently drawing its children using 4140 * their drawing cache. 4141 * 4142 * @return true if children should be drawn with their cache, false otherwise 4143 * 4144 * @see #setAlwaysDrawnWithCacheEnabled(boolean) 4145 * @see #setChildrenDrawnWithCacheEnabled(boolean) 4146 */ 4147 @ViewDebug.ExportedProperty(category = "drawing") 4148 protected boolean isChildrenDrawnWithCacheEnabled() { 4149 return (mGroupFlags & FLAG_CHILDREN_DRAWN_WITH_CACHE) == FLAG_CHILDREN_DRAWN_WITH_CACHE; 4150 } 4151 4152 /** 4153 * Tells the ViewGroup to draw its children using their drawing cache. This property 4154 * is ignored when {@link #isAlwaysDrawnWithCacheEnabled()} is true. A child's drawing cache 4155 * will be used only if it has been enabled. 4156 * 4157 * Subclasses should call this method to start and stop using the drawing cache when 4158 * they perform performance sensitive operations, like scrolling or animating. 4159 * 4160 * @param enabled true if children should be drawn with their cache, false otherwise 4161 * 4162 * @see #setAlwaysDrawnWithCacheEnabled(boolean) 4163 * @see #isChildrenDrawnWithCacheEnabled() 4164 */ 4165 protected void setChildrenDrawnWithCacheEnabled(boolean enabled) { 4166 setBooleanFlag(FLAG_CHILDREN_DRAWN_WITH_CACHE, enabled); 4167 } 4168 4169 /** 4170 * Indicates whether the ViewGroup is drawing its children in the order defined by 4171 * {@link #getChildDrawingOrder(int, int)}. 4172 * 4173 * @return true if children drawing order is defined by {@link #getChildDrawingOrder(int, int)}, 4174 * false otherwise 4175 * 4176 * @see #setChildrenDrawingOrderEnabled(boolean) 4177 * @see #getChildDrawingOrder(int, int) 4178 */ 4179 @ViewDebug.ExportedProperty(category = "drawing") 4180 protected boolean isChildrenDrawingOrderEnabled() { 4181 return (mGroupFlags & FLAG_USE_CHILD_DRAWING_ORDER) == FLAG_USE_CHILD_DRAWING_ORDER; 4182 } 4183 4184 /** 4185 * Tells the ViewGroup whether to draw its children in the order defined by the method 4186 * {@link #getChildDrawingOrder(int, int)}. 4187 * 4188 * @param enabled true if the order of the children when drawing is determined by 4189 * {@link #getChildDrawingOrder(int, int)}, false otherwise 4190 * 4191 * @see #isChildrenDrawingOrderEnabled() 4192 * @see #getChildDrawingOrder(int, int) 4193 */ 4194 protected void setChildrenDrawingOrderEnabled(boolean enabled) { 4195 setBooleanFlag(FLAG_USE_CHILD_DRAWING_ORDER, enabled); 4196 } 4197 4198 private void setBooleanFlag(int flag, boolean value) { 4199 if (value) { 4200 mGroupFlags |= flag; 4201 } else { 4202 mGroupFlags &= ~flag; 4203 } 4204 } 4205 4206 /** 4207 * Returns an integer indicating what types of drawing caches are kept in memory. 4208 * 4209 * @see #setPersistentDrawingCache(int) 4210 * @see #setAnimationCacheEnabled(boolean) 4211 * 4212 * @return one or a combination of {@link #PERSISTENT_NO_CACHE}, 4213 * {@link #PERSISTENT_ANIMATION_CACHE}, {@link #PERSISTENT_SCROLLING_CACHE} 4214 * and {@link #PERSISTENT_ALL_CACHES} 4215 */ 4216 @ViewDebug.ExportedProperty(category = "drawing", mapping = { 4217 @ViewDebug.IntToString(from = PERSISTENT_NO_CACHE, to = "NONE"), 4218 @ViewDebug.IntToString(from = PERSISTENT_ANIMATION_CACHE, to = "ANIMATION"), 4219 @ViewDebug.IntToString(from = PERSISTENT_SCROLLING_CACHE, to = "SCROLLING"), 4220 @ViewDebug.IntToString(from = PERSISTENT_ALL_CACHES, to = "ALL") 4221 }) 4222 public int getPersistentDrawingCache() { 4223 return mPersistentDrawingCache; 4224 } 4225 4226 /** 4227 * Indicates what types of drawing caches should be kept in memory after 4228 * they have been created. 4229 * 4230 * @see #getPersistentDrawingCache() 4231 * @see #setAnimationCacheEnabled(boolean) 4232 * 4233 * @param drawingCacheToKeep one or a combination of {@link #PERSISTENT_NO_CACHE}, 4234 * {@link #PERSISTENT_ANIMATION_CACHE}, {@link #PERSISTENT_SCROLLING_CACHE} 4235 * and {@link #PERSISTENT_ALL_CACHES} 4236 */ 4237 public void setPersistentDrawingCache(int drawingCacheToKeep) { 4238 mPersistentDrawingCache = drawingCacheToKeep & PERSISTENT_ALL_CACHES; 4239 } 4240 4241 /** 4242 * Returns a new set of layout parameters based on the supplied attributes set. 4243 * 4244 * @param attrs the attributes to build the layout parameters from 4245 * 4246 * @return an instance of {@link android.view.ViewGroup.LayoutParams} or one 4247 * of its descendants 4248 */ 4249 public LayoutParams generateLayoutParams(AttributeSet attrs) { 4250 return new LayoutParams(getContext(), attrs); 4251 } 4252 4253 /** 4254 * Returns a safe set of layout parameters based on the supplied layout params. 4255 * When a ViewGroup is passed a View whose layout params do not pass the test of 4256 * {@link #checkLayoutParams(android.view.ViewGroup.LayoutParams)}, this method 4257 * is invoked. This method should return a new set of layout params suitable for 4258 * this ViewGroup, possibly by copying the appropriate attributes from the 4259 * specified set of layout params. 4260 * 4261 * @param p The layout parameters to convert into a suitable set of layout parameters 4262 * for this ViewGroup. 4263 * 4264 * @return an instance of {@link android.view.ViewGroup.LayoutParams} or one 4265 * of its descendants 4266 */ 4267 protected LayoutParams generateLayoutParams(ViewGroup.LayoutParams p) { 4268 return p; 4269 } 4270 4271 /** 4272 * Returns a set of default layout parameters. These parameters are requested 4273 * when the View passed to {@link #addView(View)} has no layout parameters 4274 * already set. If null is returned, an exception is thrown from addView. 4275 * 4276 * @return a set of default layout parameters or null 4277 */ 4278 protected LayoutParams generateDefaultLayoutParams() { 4279 return new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT); 4280 } 4281 4282 /** 4283 * @hide 4284 */ 4285 @Override 4286 protected boolean dispatchConsistencyCheck(int consistency) { 4287 boolean result = super.dispatchConsistencyCheck(consistency); 4288 4289 final int count = mChildrenCount; 4290 final View[] children = mChildren; 4291 for (int i = 0; i < count; i++) { 4292 if (!children[i].dispatchConsistencyCheck(consistency)) result = false; 4293 } 4294 4295 return result; 4296 } 4297 4298 /** 4299 * @hide 4300 */ 4301 @Override 4302 protected boolean onConsistencyCheck(int consistency) { 4303 boolean result = super.onConsistencyCheck(consistency); 4304 4305 final boolean checkLayout = (consistency & ViewDebug.CONSISTENCY_LAYOUT) != 0; 4306 final boolean checkDrawing = (consistency & ViewDebug.CONSISTENCY_DRAWING) != 0; 4307 4308 if (checkLayout) { 4309 final int count = mChildrenCount; 4310 final View[] children = mChildren; 4311 for (int i = 0; i < count; i++) { 4312 if (children[i].getParent() != this) { 4313 result = false; 4314 android.util.Log.d(ViewDebug.CONSISTENCY_LOG_TAG, 4315 "View " + children[i] + " has no parent/a parent that is not " + this); 4316 } 4317 } 4318 } 4319 4320 if (checkDrawing) { 4321 // If this group is dirty, check that the parent is dirty as well 4322 if ((mPrivateFlags & DIRTY_MASK) != 0) { 4323 final ViewParent parent = getParent(); 4324 if (parent != null && !(parent instanceof ViewRootImpl)) { 4325 if ((((View) parent).mPrivateFlags & DIRTY_MASK) == 0) { 4326 result = false; 4327 android.util.Log.d(ViewDebug.CONSISTENCY_LOG_TAG, 4328 "ViewGroup " + this + " is dirty but its parent is not: " + this); 4329 } 4330 } 4331 } 4332 } 4333 4334 return result; 4335 } 4336 4337 /** 4338 * {@inheritDoc} 4339 */ 4340 @Override 4341 protected void debug(int depth) { 4342 super.debug(depth); 4343 String output; 4344 4345 if (mFocused != null) { 4346 output = debugIndent(depth); 4347 output += "mFocused"; 4348 Log.d(VIEW_LOG_TAG, output); 4349 } 4350 if (mChildrenCount != 0) { 4351 output = debugIndent(depth); 4352 output += "{"; 4353 Log.d(VIEW_LOG_TAG, output); 4354 } 4355 int count = mChildrenCount; 4356 for (int i = 0; i < count; i++) { 4357 View child = mChildren[i]; 4358 child.debug(depth + 1); 4359 } 4360 4361 if (mChildrenCount != 0) { 4362 output = debugIndent(depth); 4363 output += "}"; 4364 Log.d(VIEW_LOG_TAG, output); 4365 } 4366 } 4367 4368 /** 4369 * Returns the position in the group of the specified child view. 4370 * 4371 * @param child the view for which to get the position 4372 * @return a positive integer representing the position of the view in the 4373 * group, or -1 if the view does not exist in the group 4374 */ 4375 public int indexOfChild(View child) { 4376 final int count = mChildrenCount; 4377 final View[] children = mChildren; 4378 for (int i = 0; i < count; i++) { 4379 if (children[i] == child) { 4380 return i; 4381 } 4382 } 4383 return -1; 4384 } 4385 4386 /** 4387 * Returns the number of children in the group. 4388 * 4389 * @return a positive integer representing the number of children in 4390 * the group 4391 */ 4392 public int getChildCount() { 4393 return mChildrenCount; 4394 } 4395 4396 /** 4397 * Returns the view at the specified position in the group. 4398 * 4399 * @param index the position at which to get the view from 4400 * @return the view at the specified position or null if the position 4401 * does not exist within the group 4402 */ 4403 public View getChildAt(int index) { 4404 if (index < 0 || index >= mChildrenCount) { 4405 return null; 4406 } 4407 return mChildren[index]; 4408 } 4409 4410 /** 4411 * Ask all of the children of this view to measure themselves, taking into 4412 * account both the MeasureSpec requirements for this view and its padding. 4413 * We skip children that are in the GONE state The heavy lifting is done in 4414 * getChildMeasureSpec. 4415 * 4416 * @param widthMeasureSpec The width requirements for this view 4417 * @param heightMeasureSpec The height requirements for this view 4418 */ 4419 protected void measureChildren(int widthMeasureSpec, int heightMeasureSpec) { 4420 final int size = mChildrenCount; 4421 final View[] children = mChildren; 4422 for (int i = 0; i < size; ++i) { 4423 final View child = children[i]; 4424 if ((child.mViewFlags & VISIBILITY_MASK) != GONE) { 4425 measureChild(child, widthMeasureSpec, heightMeasureSpec); 4426 } 4427 } 4428 } 4429 4430 /** 4431 * Ask one of the children of this view to measure itself, taking into 4432 * account both the MeasureSpec requirements for this view and its padding. 4433 * The heavy lifting is done in getChildMeasureSpec. 4434 * 4435 * @param child The child to measure 4436 * @param parentWidthMeasureSpec The width requirements for this view 4437 * @param parentHeightMeasureSpec The height requirements for this view 4438 */ 4439 protected void measureChild(View child, int parentWidthMeasureSpec, 4440 int parentHeightMeasureSpec) { 4441 final LayoutParams lp = child.getLayoutParams(); 4442 4443 final int childWidthMeasureSpec = getChildMeasureSpec(parentWidthMeasureSpec, 4444 mPaddingLeft + mPaddingRight, lp.width); 4445 final int childHeightMeasureSpec = getChildMeasureSpec(parentHeightMeasureSpec, 4446 mPaddingTop + mPaddingBottom, lp.height); 4447 4448 child.measure(childWidthMeasureSpec, childHeightMeasureSpec); 4449 } 4450 4451 /** 4452 * Ask one of the children of this view to measure itself, taking into 4453 * account both the MeasureSpec requirements for this view and its padding 4454 * and margins. The child must have MarginLayoutParams The heavy lifting is 4455 * done in getChildMeasureSpec. 4456 * 4457 * @param child The child to measure 4458 * @param parentWidthMeasureSpec The width requirements for this view 4459 * @param widthUsed Extra space that has been used up by the parent 4460 * horizontally (possibly by other children of the parent) 4461 * @param parentHeightMeasureSpec The height requirements for this view 4462 * @param heightUsed Extra space that has been used up by the parent 4463 * vertically (possibly by other children of the parent) 4464 */ 4465 protected void measureChildWithMargins(View child, 4466 int parentWidthMeasureSpec, int widthUsed, 4467 int parentHeightMeasureSpec, int heightUsed) { 4468 final MarginLayoutParams lp = (MarginLayoutParams) child.getLayoutParams(); 4469 4470 final int childWidthMeasureSpec = getChildMeasureSpec(parentWidthMeasureSpec, 4471 mPaddingLeft + mPaddingRight + lp.leftMargin + lp.rightMargin 4472 + widthUsed, lp.width); 4473 final int childHeightMeasureSpec = getChildMeasureSpec(parentHeightMeasureSpec, 4474 mPaddingTop + mPaddingBottom + lp.topMargin + lp.bottomMargin 4475 + heightUsed, lp.height); 4476 4477 child.measure(childWidthMeasureSpec, childHeightMeasureSpec); 4478 } 4479 4480 /** 4481 * Does the hard part of measureChildren: figuring out the MeasureSpec to 4482 * pass to a particular child. This method figures out the right MeasureSpec 4483 * for one dimension (height or width) of one child view. 4484 * 4485 * The goal is to combine information from our MeasureSpec with the 4486 * LayoutParams of the child to get the best possible results. For example, 4487 * if the this view knows its size (because its MeasureSpec has a mode of 4488 * EXACTLY), and the child has indicated in its LayoutParams that it wants 4489 * to be the same size as the parent, the parent should ask the child to 4490 * layout given an exact size. 4491 * 4492 * @param spec The requirements for this view 4493 * @param padding The padding of this view for the current dimension and 4494 * margins, if applicable 4495 * @param childDimension How big the child wants to be in the current 4496 * dimension 4497 * @return a MeasureSpec integer for the child 4498 */ 4499 public static int getChildMeasureSpec(int spec, int padding, int childDimension) { 4500 int specMode = MeasureSpec.getMode(spec); 4501 int specSize = MeasureSpec.getSize(spec); 4502 4503 int size = Math.max(0, specSize - padding); 4504 4505 int resultSize = 0; 4506 int resultMode = 0; 4507 4508 switch (specMode) { 4509 // Parent has imposed an exact size on us 4510 case MeasureSpec.EXACTLY: 4511 if (childDimension >= 0) { 4512 resultSize = childDimension; 4513 resultMode = MeasureSpec.EXACTLY; 4514 } else if (childDimension == LayoutParams.MATCH_PARENT) { 4515 // Child wants to be our size. So be it. 4516 resultSize = size; 4517 resultMode = MeasureSpec.EXACTLY; 4518 } else if (childDimension == LayoutParams.WRAP_CONTENT) { 4519 // Child wants to determine its own size. It can't be 4520 // bigger than us. 4521 resultSize = size; 4522 resultMode = MeasureSpec.AT_MOST; 4523 } 4524 break; 4525 4526 // Parent has imposed a maximum size on us 4527 case MeasureSpec.AT_MOST: 4528 if (childDimension >= 0) { 4529 // Child wants a specific size... so be it 4530 resultSize = childDimension; 4531 resultMode = MeasureSpec.EXACTLY; 4532 } else if (childDimension == LayoutParams.MATCH_PARENT) { 4533 // Child wants to be our size, but our size is not fixed. 4534 // Constrain child to not be bigger than us. 4535 resultSize = size; 4536 resultMode = MeasureSpec.AT_MOST; 4537 } else if (childDimension == LayoutParams.WRAP_CONTENT) { 4538 // Child wants to determine its own size. It can't be 4539 // bigger than us. 4540 resultSize = size; 4541 resultMode = MeasureSpec.AT_MOST; 4542 } 4543 break; 4544 4545 // Parent asked to see how big we want to be 4546 case MeasureSpec.UNSPECIFIED: 4547 if (childDimension >= 0) { 4548 // Child wants a specific size... let him have it 4549 resultSize = childDimension; 4550 resultMode = MeasureSpec.EXACTLY; 4551 } else if (childDimension == LayoutParams.MATCH_PARENT) { 4552 // Child wants to be our size... find out how big it should 4553 // be 4554 resultSize = 0; 4555 resultMode = MeasureSpec.UNSPECIFIED; 4556 } else if (childDimension == LayoutParams.WRAP_CONTENT) { 4557 // Child wants to determine its own size.... find out how 4558 // big it should be 4559 resultSize = 0; 4560 resultMode = MeasureSpec.UNSPECIFIED; 4561 } 4562 break; 4563 } 4564 return MeasureSpec.makeMeasureSpec(resultSize, resultMode); 4565 } 4566 4567 4568 /** 4569 * Removes any pending animations for views that have been removed. Call 4570 * this if you don't want animations for exiting views to stack up. 4571 */ 4572 public void clearDisappearingChildren() { 4573 if (mDisappearingChildren != null) { 4574 mDisappearingChildren.clear(); 4575 } 4576 } 4577 4578 /** 4579 * Add a view which is removed from mChildren but still needs animation 4580 * 4581 * @param v View to add 4582 */ 4583 private void addDisappearingView(View v) { 4584 ArrayList<View> disappearingChildren = mDisappearingChildren; 4585 4586 if (disappearingChildren == null) { 4587 disappearingChildren = mDisappearingChildren = new ArrayList<View>(); 4588 } 4589 4590 disappearingChildren.add(v); 4591 } 4592 4593 /** 4594 * Cleanup a view when its animation is done. This may mean removing it from 4595 * the list of disappearing views. 4596 * 4597 * @param view The view whose animation has finished 4598 * @param animation The animation, cannot be null 4599 */ 4600 void finishAnimatingView(final View view, Animation animation) { 4601 final ArrayList<View> disappearingChildren = mDisappearingChildren; 4602 if (disappearingChildren != null) { 4603 if (disappearingChildren.contains(view)) { 4604 disappearingChildren.remove(view); 4605 4606 if (view.mAttachInfo != null) { 4607 view.dispatchDetachedFromWindow(); 4608 } 4609 4610 view.clearAnimation(); 4611 mGroupFlags |= FLAG_INVALIDATE_REQUIRED; 4612 } 4613 } 4614 4615 if (animation != null && !animation.getFillAfter()) { 4616 view.clearAnimation(); 4617 } 4618 4619 if ((view.mPrivateFlags & ANIMATION_STARTED) == ANIMATION_STARTED) { 4620 view.onAnimationEnd(); 4621 // Should be performed by onAnimationEnd() but this avoid an infinite loop, 4622 // so we'd rather be safe than sorry 4623 view.mPrivateFlags &= ~ANIMATION_STARTED; 4624 // Draw one more frame after the animation is done 4625 mGroupFlags |= FLAG_INVALIDATE_REQUIRED; 4626 } 4627 } 4628 4629 /** 4630 * Utility function called by View during invalidation to determine whether a view that 4631 * is invisible or gone should still be invalidated because it is being transitioned (and 4632 * therefore still needs to be drawn). 4633 */ 4634 boolean isViewTransitioning(View view) { 4635 return (mTransitioningViews != null && mTransitioningViews.contains(view)); 4636 } 4637 4638 /** 4639 * This method tells the ViewGroup that the given View object, which should have this 4640 * ViewGroup as its parent, 4641 * should be kept around (re-displayed when the ViewGroup draws its children) even if it 4642 * is removed from its parent. This allows animations, such as those used by 4643 * {@link android.app.Fragment} and {@link android.animation.LayoutTransition} to animate 4644 * the removal of views. A call to this method should always be accompanied by a later call 4645 * to {@link #endViewTransition(View)}, such as after an animation on the View has finished, 4646 * so that the View finally gets removed. 4647 * 4648 * @param view The View object to be kept visible even if it gets removed from its parent. 4649 */ 4650 public void startViewTransition(View view) { 4651 if (view.mParent == this) { 4652 if (mTransitioningViews == null) { 4653 mTransitioningViews = new ArrayList<View>(); 4654 } 4655 mTransitioningViews.add(view); 4656 } 4657 } 4658 4659 /** 4660 * This method should always be called following an earlier call to 4661 * {@link #startViewTransition(View)}. The given View is finally removed from its parent 4662 * and will no longer be displayed. Note that this method does not perform the functionality 4663 * of removing a view from its parent; it just discontinues the display of a View that 4664 * has previously been removed. 4665 * 4666 * @return view The View object that has been removed but is being kept around in the visible 4667 * hierarchy by an earlier call to {@link #startViewTransition(View)}. 4668 */ 4669 public void endViewTransition(View view) { 4670 if (mTransitioningViews != null) { 4671 mTransitioningViews.remove(view); 4672 final ArrayList<View> disappearingChildren = mDisappearingChildren; 4673 if (disappearingChildren != null && disappearingChildren.contains(view)) { 4674 disappearingChildren.remove(view); 4675 if (mVisibilityChangingChildren != null && 4676 mVisibilityChangingChildren.contains(view)) { 4677 mVisibilityChangingChildren.remove(view); 4678 } else { 4679 if (view.mAttachInfo != null) { 4680 view.dispatchDetachedFromWindow(); 4681 } 4682 if (view.mParent != null) { 4683 view.mParent = null; 4684 } 4685 } 4686 mGroupFlags |= FLAG_INVALIDATE_REQUIRED; 4687 } 4688 } 4689 } 4690 4691 private LayoutTransition.TransitionListener mLayoutTransitionListener = 4692 new LayoutTransition.TransitionListener() { 4693 @Override 4694 public void startTransition(LayoutTransition transition, ViewGroup container, 4695 View view, int transitionType) { 4696 // We only care about disappearing items, since we need special logic to keep 4697 // those items visible after they've been 'removed' 4698 if (transitionType == LayoutTransition.DISAPPEARING) { 4699 startViewTransition(view); 4700 } 4701 } 4702 4703 @Override 4704 public void endTransition(LayoutTransition transition, ViewGroup container, 4705 View view, int transitionType) { 4706 if (mLayoutSuppressed && !transition.isChangingLayout()) { 4707 requestLayout(); 4708 mLayoutSuppressed = false; 4709 } 4710 if (transitionType == LayoutTransition.DISAPPEARING && mTransitioningViews != null) { 4711 endViewTransition(view); 4712 } 4713 } 4714 }; 4715 4716 /** 4717 * {@inheritDoc} 4718 */ 4719 @Override 4720 public boolean gatherTransparentRegion(Region region) { 4721 // If no transparent regions requested, we are always opaque. 4722 final boolean meOpaque = (mPrivateFlags & View.REQUEST_TRANSPARENT_REGIONS) == 0; 4723 if (meOpaque && region == null) { 4724 // The caller doesn't care about the region, so stop now. 4725 return true; 4726 } 4727 super.gatherTransparentRegion(region); 4728 final View[] children = mChildren; 4729 final int count = mChildrenCount; 4730 boolean noneOfTheChildrenAreTransparent = true; 4731 for (int i = 0; i < count; i++) { 4732 final View child = children[i]; 4733 if ((child.mViewFlags & VISIBILITY_MASK) == VISIBLE || child.getAnimation() != null) { 4734 if (!child.gatherTransparentRegion(region)) { 4735 noneOfTheChildrenAreTransparent = false; 4736 } 4737 } 4738 } 4739 return meOpaque || noneOfTheChildrenAreTransparent; 4740 } 4741 4742 /** 4743 * {@inheritDoc} 4744 */ 4745 public void requestTransparentRegion(View child) { 4746 if (child != null) { 4747 child.mPrivateFlags |= View.REQUEST_TRANSPARENT_REGIONS; 4748 if (mParent != null) { 4749 mParent.requestTransparentRegion(this); 4750 } 4751 } 4752 } 4753 4754 4755 @Override 4756 protected boolean fitSystemWindows(Rect insets) { 4757 boolean done = super.fitSystemWindows(insets); 4758 if (!done) { 4759 final int count = mChildrenCount; 4760 final View[] children = mChildren; 4761 for (int i = 0; i < count; i++) { 4762 done = children[i].fitSystemWindows(insets); 4763 if (done) { 4764 break; 4765 } 4766 } 4767 } 4768 return done; 4769 } 4770 4771 /** 4772 * Returns the animation listener to which layout animation events are 4773 * sent. 4774 * 4775 * @return an {@link android.view.animation.Animation.AnimationListener} 4776 */ 4777 public Animation.AnimationListener getLayoutAnimationListener() { 4778 return mAnimationListener; 4779 } 4780 4781 @Override 4782 protected void drawableStateChanged() { 4783 super.drawableStateChanged(); 4784 4785 if ((mGroupFlags & FLAG_NOTIFY_CHILDREN_ON_DRAWABLE_STATE_CHANGE) != 0) { 4786 if ((mGroupFlags & FLAG_ADD_STATES_FROM_CHILDREN) != 0) { 4787 throw new IllegalStateException("addStateFromChildren cannot be enabled if a" 4788 + " child has duplicateParentState set to true"); 4789 } 4790 4791 final View[] children = mChildren; 4792 final int count = mChildrenCount; 4793 4794 for (int i = 0; i < count; i++) { 4795 final View child = children[i]; 4796 if ((child.mViewFlags & DUPLICATE_PARENT_STATE) != 0) { 4797 child.refreshDrawableState(); 4798 } 4799 } 4800 } 4801 } 4802 4803 @Override 4804 public void jumpDrawablesToCurrentState() { 4805 super.jumpDrawablesToCurrentState(); 4806 final View[] children = mChildren; 4807 final int count = mChildrenCount; 4808 for (int i = 0; i < count; i++) { 4809 children[i].jumpDrawablesToCurrentState(); 4810 } 4811 } 4812 4813 @Override 4814 protected int[] onCreateDrawableState(int extraSpace) { 4815 if ((mGroupFlags & FLAG_ADD_STATES_FROM_CHILDREN) == 0) { 4816 return super.onCreateDrawableState(extraSpace); 4817 } 4818 4819 int need = 0; 4820 int n = getChildCount(); 4821 for (int i = 0; i < n; i++) { 4822 int[] childState = getChildAt(i).getDrawableState(); 4823 4824 if (childState != null) { 4825 need += childState.length; 4826 } 4827 } 4828 4829 int[] state = super.onCreateDrawableState(extraSpace + need); 4830 4831 for (int i = 0; i < n; i++) { 4832 int[] childState = getChildAt(i).getDrawableState(); 4833 4834 if (childState != null) { 4835 state = mergeDrawableStates(state, childState); 4836 } 4837 } 4838 4839 return state; 4840 } 4841 4842 /** 4843 * Sets whether this ViewGroup's drawable states also include 4844 * its children's drawable states. This is used, for example, to 4845 * make a group appear to be focused when its child EditText or button 4846 * is focused. 4847 */ 4848 public void setAddStatesFromChildren(boolean addsStates) { 4849 if (addsStates) { 4850 mGroupFlags |= FLAG_ADD_STATES_FROM_CHILDREN; 4851 } else { 4852 mGroupFlags &= ~FLAG_ADD_STATES_FROM_CHILDREN; 4853 } 4854 4855 refreshDrawableState(); 4856 } 4857 4858 /** 4859 * Returns whether this ViewGroup's drawable states also include 4860 * its children's drawable states. This is used, for example, to 4861 * make a group appear to be focused when its child EditText or button 4862 * is focused. 4863 */ 4864 public boolean addStatesFromChildren() { 4865 return (mGroupFlags & FLAG_ADD_STATES_FROM_CHILDREN) != 0; 4866 } 4867 4868 /** 4869 * If {link #addStatesFromChildren} is true, refreshes this group's 4870 * drawable state (to include the states from its children). 4871 */ 4872 public void childDrawableStateChanged(View child) { 4873 if ((mGroupFlags & FLAG_ADD_STATES_FROM_CHILDREN) != 0) { 4874 refreshDrawableState(); 4875 } 4876 } 4877 4878 /** 4879 * Specifies the animation listener to which layout animation events must 4880 * be sent. Only 4881 * {@link android.view.animation.Animation.AnimationListener#onAnimationStart(Animation)} 4882 * and 4883 * {@link android.view.animation.Animation.AnimationListener#onAnimationEnd(Animation)} 4884 * are invoked. 4885 * 4886 * @param animationListener the layout animation listener 4887 */ 4888 public void setLayoutAnimationListener(Animation.AnimationListener animationListener) { 4889 mAnimationListener = animationListener; 4890 } 4891 4892 /** 4893 * This method is called by LayoutTransition when there are 'changing' animations that need 4894 * to start after the layout/setup phase. The request is forwarded to the ViewAncestor, who 4895 * starts all pending transitions prior to the drawing phase in the current traversal. 4896 * 4897 * @param transition The LayoutTransition to be started on the next traversal. 4898 * 4899 * @hide 4900 */ 4901 public void requestTransitionStart(LayoutTransition transition) { 4902 ViewRootImpl viewAncestor = getViewRootImpl(); 4903 if (viewAncestor != null) { 4904 viewAncestor.requestTransitionStart(transition); 4905 } 4906 } 4907 4908 @Override 4909 protected void resetResolvedLayoutDirection() { 4910 super.resetResolvedLayoutDirection(); 4911 4912 // Take care of resetting the children resolution too 4913 final int count = getChildCount(); 4914 for (int i = 0; i < count; i++) { 4915 final View child = getChildAt(i); 4916 if (child.getLayoutDirection() == LAYOUT_DIRECTION_INHERIT) { 4917 child.resetResolvedLayoutDirection(); 4918 } 4919 } 4920 } 4921 4922 @Override 4923 public void onResetResolvedTextDirection() { 4924 // Take care of resetting the children resolution too 4925 final int count = getChildCount(); 4926 for (int i = 0; i < count; i++) { 4927 final View child = getChildAt(i); 4928 if (child.getTextDirection() == TEXT_DIRECTION_INHERIT) { 4929 child.resetResolvedTextDirection(); 4930 } 4931 } 4932 } 4933 4934 /** 4935 * Return true if the pressed state should be delayed for children or descendants of this 4936 * ViewGroup. Generally, this should be done for containers that can scroll, such as a List. 4937 * This prevents the pressed state from appearing when the user is actually trying to scroll 4938 * the content. 4939 * 4940 * The default implementation returns true for compatibility reasons. Subclasses that do 4941 * not scroll should generally override this method and return false. 4942 */ 4943 public boolean shouldDelayChildPressedState() { 4944 return true; 4945 } 4946 4947 /** @hide */ 4948 protected void onSetLayoutParams(View child, LayoutParams layoutParams) { 4949 } 4950 4951 /** 4952 * LayoutParams are used by views to tell their parents how they want to be 4953 * laid out. See 4954 * {@link android.R.styleable#ViewGroup_Layout ViewGroup Layout Attributes} 4955 * for a list of all child view attributes that this class supports. 4956 * 4957 * <p> 4958 * The base LayoutParams class just describes how big the view wants to be 4959 * for both width and height. For each dimension, it can specify one of: 4960 * <ul> 4961 * <li>FILL_PARENT (renamed MATCH_PARENT in API Level 8 and higher), which 4962 * means that the view wants to be as big as its parent (minus padding) 4963 * <li> WRAP_CONTENT, which means that the view wants to be just big enough 4964 * to enclose its content (plus padding) 4965 * <li> an exact number 4966 * </ul> 4967 * There are subclasses of LayoutParams for different subclasses of 4968 * ViewGroup. For example, AbsoluteLayout has its own subclass of 4969 * LayoutParams which adds an X and Y value.</p> 4970 * 4971 * <div class="special reference"> 4972 * <h3>Developer Guides</h3> 4973 * <p>For more information about creating user interface layouts, read the 4974 * <a href="{@docRoot}guide/topics/ui/declaring-layout.html">XML Layouts</a> developer 4975 * guide.</p></div> 4976 * 4977 * @attr ref android.R.styleable#ViewGroup_Layout_layout_height 4978 * @attr ref android.R.styleable#ViewGroup_Layout_layout_width 4979 */ 4980 public static class LayoutParams { 4981 /** 4982 * Special value for the height or width requested by a View. 4983 * FILL_PARENT means that the view wants to be as big as its parent, 4984 * minus the parent's padding, if any. This value is deprecated 4985 * starting in API Level 8 and replaced by {@link #MATCH_PARENT}. 4986 */ 4987 @SuppressWarnings({"UnusedDeclaration"}) 4988 @Deprecated 4989 public static final int FILL_PARENT = -1; 4990 4991 /** 4992 * Special value for the height or width requested by a View. 4993 * MATCH_PARENT means that the view wants to be as big as its parent, 4994 * minus the parent's padding, if any. Introduced in API Level 8. 4995 */ 4996 public static final int MATCH_PARENT = -1; 4997 4998 /** 4999 * Special value for the height or width requested by a View. 5000 * WRAP_CONTENT means that the view wants to be just large enough to fit 5001 * its own internal content, taking its own padding into account. 5002 */ 5003 public static final int WRAP_CONTENT = -2; 5004 5005 /** 5006 * Information about how wide the view wants to be. Can be one of the 5007 * constants FILL_PARENT (replaced by MATCH_PARENT , 5008 * in API Level 8) or WRAP_CONTENT. or an exact size. 5009 */ 5010 @ViewDebug.ExportedProperty(category = "layout", mapping = { 5011 @ViewDebug.IntToString(from = MATCH_PARENT, to = "MATCH_PARENT"), 5012 @ViewDebug.IntToString(from = WRAP_CONTENT, to = "WRAP_CONTENT") 5013 }) 5014 public int width; 5015 5016 /** 5017 * Information about how tall the view wants to be. Can be one of the 5018 * constants FILL_PARENT (replaced by MATCH_PARENT , 5019 * in API Level 8) or WRAP_CONTENT. or an exact size. 5020 */ 5021 @ViewDebug.ExportedProperty(category = "layout", mapping = { 5022 @ViewDebug.IntToString(from = MATCH_PARENT, to = "MATCH_PARENT"), 5023 @ViewDebug.IntToString(from = WRAP_CONTENT, to = "WRAP_CONTENT") 5024 }) 5025 public int height; 5026 5027 /** 5028 * Used to animate layouts. 5029 */ 5030 public LayoutAnimationController.AnimationParameters layoutAnimationParameters; 5031 5032 /** 5033 * Creates a new set of layout parameters. The values are extracted from 5034 * the supplied attributes set and context. The XML attributes mapped 5035 * to this set of layout parameters are: 5036 * 5037 * <ul> 5038 * <li><code>layout_width</code>: the width, either an exact value, 5039 * {@link #WRAP_CONTENT}, or {@link #FILL_PARENT} (replaced by 5040 * {@link #MATCH_PARENT} in API Level 8)</li> 5041 * <li><code>layout_height</code>: the height, either an exact value, 5042 * {@link #WRAP_CONTENT}, or {@link #FILL_PARENT} (replaced by 5043 * {@link #MATCH_PARENT} in API Level 8)</li> 5044 * </ul> 5045 * 5046 * @param c the application environment 5047 * @param attrs the set of attributes from which to extract the layout 5048 * parameters' values 5049 */ 5050 public LayoutParams(Context c, AttributeSet attrs) { 5051 TypedArray a = c.obtainStyledAttributes(attrs, R.styleable.ViewGroup_Layout); 5052 setBaseAttributes(a, 5053 R.styleable.ViewGroup_Layout_layout_width, 5054 R.styleable.ViewGroup_Layout_layout_height); 5055 a.recycle(); 5056 } 5057 5058 /** 5059 * Creates a new set of layout parameters with the specified width 5060 * and height. 5061 * 5062 * @param width the width, either {@link #WRAP_CONTENT}, 5063 * {@link #FILL_PARENT} (replaced by {@link #MATCH_PARENT} in 5064 * API Level 8), or a fixed size in pixels 5065 * @param height the height, either {@link #WRAP_CONTENT}, 5066 * {@link #FILL_PARENT} (replaced by {@link #MATCH_PARENT} in 5067 * API Level 8), or a fixed size in pixels 5068 */ 5069 public LayoutParams(int width, int height) { 5070 this.width = width; 5071 this.height = height; 5072 } 5073 5074 /** 5075 * Copy constructor. Clones the width and height values of the source. 5076 * 5077 * @param source The layout params to copy from. 5078 */ 5079 public LayoutParams(LayoutParams source) { 5080 this.width = source.width; 5081 this.height = source.height; 5082 } 5083 5084 /** 5085 * Used internally by MarginLayoutParams. 5086 * @hide 5087 */ 5088 LayoutParams() { 5089 } 5090 5091 /** 5092 * Extracts the layout parameters from the supplied attributes. 5093 * 5094 * @param a the style attributes to extract the parameters from 5095 * @param widthAttr the identifier of the width attribute 5096 * @param heightAttr the identifier of the height attribute 5097 */ 5098 protected void setBaseAttributes(TypedArray a, int widthAttr, int heightAttr) { 5099 width = a.getLayoutDimension(widthAttr, "layout_width"); 5100 height = a.getLayoutDimension(heightAttr, "layout_height"); 5101 } 5102 5103 /** 5104 * Resolve layout parameters depending on the layout direction. Subclasses that care about 5105 * layoutDirection changes should override this method. The default implementation does 5106 * nothing. 5107 * 5108 * @param layoutDirection the direction of the layout 5109 * 5110 * {@link View#LAYOUT_DIRECTION_LTR} 5111 * {@link View#LAYOUT_DIRECTION_RTL} 5112 * 5113 * @hide 5114 */ 5115 protected void resolveWithDirection(int layoutDirection) { 5116 } 5117 5118 /** 5119 * Returns a String representation of this set of layout parameters. 5120 * 5121 * @param output the String to prepend to the internal representation 5122 * @return a String with the following format: output + 5123 * "ViewGroup.LayoutParams={ width=WIDTH, height=HEIGHT }" 5124 * 5125 * @hide 5126 */ 5127 public String debug(String output) { 5128 return output + "ViewGroup.LayoutParams={ width=" 5129 + sizeToString(width) + ", height=" + sizeToString(height) + " }"; 5130 } 5131 5132 /** 5133 * Converts the specified size to a readable String. 5134 * 5135 * @param size the size to convert 5136 * @return a String instance representing the supplied size 5137 * 5138 * @hide 5139 */ 5140 protected static String sizeToString(int size) { 5141 if (size == WRAP_CONTENT) { 5142 return "wrap-content"; 5143 } 5144 if (size == MATCH_PARENT) { 5145 return "match-parent"; 5146 } 5147 return String.valueOf(size); 5148 } 5149 } 5150 5151 /** 5152 * Per-child layout information for layouts that support margins. 5153 * See 5154 * {@link android.R.styleable#ViewGroup_MarginLayout ViewGroup Margin Layout Attributes} 5155 * for a list of all child view attributes that this class supports. 5156 */ 5157 public static class MarginLayoutParams extends ViewGroup.LayoutParams { 5158 /** 5159 * The left margin in pixels of the child. 5160 * Call {@link ViewGroup#setLayoutParams(LayoutParams)} after reassigning a new value 5161 * to this field. 5162 */ 5163 @ViewDebug.ExportedProperty(category = "layout") 5164 public int leftMargin; 5165 5166 /** 5167 * The top margin in pixels of the child. 5168 * Call {@link ViewGroup#setLayoutParams(LayoutParams)} after reassigning a new value 5169 * to this field. 5170 */ 5171 @ViewDebug.ExportedProperty(category = "layout") 5172 public int topMargin; 5173 5174 /** 5175 * The right margin in pixels of the child. 5176 * Call {@link ViewGroup#setLayoutParams(LayoutParams)} after reassigning a new value 5177 * to this field. 5178 */ 5179 @ViewDebug.ExportedProperty(category = "layout") 5180 public int rightMargin; 5181 5182 /** 5183 * The bottom margin in pixels of the child. 5184 * Call {@link ViewGroup#setLayoutParams(LayoutParams)} after reassigning a new value 5185 * to this field. 5186 */ 5187 @ViewDebug.ExportedProperty(category = "layout") 5188 public int bottomMargin; 5189 5190 /** 5191 * The start margin in pixels of the child. 5192 * Call {@link ViewGroup#setLayoutParams(LayoutParams)} after reassigning a new value 5193 * to this field. 5194 */ 5195 @ViewDebug.ExportedProperty(category = "layout") 5196 public int startMargin = DEFAULT_RELATIVE; 5197 5198 /** 5199 * The end margin in pixels of the child. 5200 * Call {@link ViewGroup#setLayoutParams(LayoutParams)} after reassigning a new value 5201 * to this field. 5202 */ 5203 @ViewDebug.ExportedProperty(category = "layout") 5204 public int endMargin = DEFAULT_RELATIVE; 5205 5206 /** 5207 * The default start and end margin. 5208 */ 5209 static private final int DEFAULT_RELATIVE = Integer.MIN_VALUE; 5210 5211 /** 5212 * Creates a new set of layout parameters. The values are extracted from 5213 * the supplied attributes set and context. 5214 * 5215 * @param c the application environment 5216 * @param attrs the set of attributes from which to extract the layout 5217 * parameters' values 5218 */ 5219 public MarginLayoutParams(Context c, AttributeSet attrs) { 5220 super(); 5221 5222 TypedArray a = c.obtainStyledAttributes(attrs, R.styleable.ViewGroup_MarginLayout); 5223 setBaseAttributes(a, 5224 R.styleable.ViewGroup_MarginLayout_layout_width, 5225 R.styleable.ViewGroup_MarginLayout_layout_height); 5226 5227 int margin = a.getDimensionPixelSize( 5228 com.android.internal.R.styleable.ViewGroup_MarginLayout_layout_margin, -1); 5229 if (margin >= 0) { 5230 leftMargin = margin; 5231 topMargin = margin; 5232 rightMargin= margin; 5233 bottomMargin = margin; 5234 } else { 5235 leftMargin = a.getDimensionPixelSize( 5236 R.styleable.ViewGroup_MarginLayout_layout_marginLeft, 0); 5237 topMargin = a.getDimensionPixelSize( 5238 R.styleable.ViewGroup_MarginLayout_layout_marginTop, 0); 5239 rightMargin = a.getDimensionPixelSize( 5240 R.styleable.ViewGroup_MarginLayout_layout_marginRight, 0); 5241 bottomMargin = a.getDimensionPixelSize( 5242 R.styleable.ViewGroup_MarginLayout_layout_marginBottom, 0); 5243 startMargin = a.getDimensionPixelSize( 5244 R.styleable.ViewGroup_MarginLayout_layout_marginStart, DEFAULT_RELATIVE); 5245 endMargin = a.getDimensionPixelSize( 5246 R.styleable.ViewGroup_MarginLayout_layout_marginEnd, DEFAULT_RELATIVE); 5247 } 5248 5249 a.recycle(); 5250 } 5251 5252 /** 5253 * {@inheritDoc} 5254 */ 5255 public MarginLayoutParams(int width, int height) { 5256 super(width, height); 5257 } 5258 5259 /** 5260 * Copy constructor. Clones the width, height and margin values of the source. 5261 * 5262 * @param source The layout params to copy from. 5263 */ 5264 public MarginLayoutParams(MarginLayoutParams source) { 5265 this.width = source.width; 5266 this.height = source.height; 5267 5268 this.leftMargin = source.leftMargin; 5269 this.topMargin = source.topMargin; 5270 this.rightMargin = source.rightMargin; 5271 this.bottomMargin = source.bottomMargin; 5272 this.startMargin = source.startMargin; 5273 this.endMargin = source.endMargin; 5274 } 5275 5276 /** 5277 * {@inheritDoc} 5278 */ 5279 public MarginLayoutParams(LayoutParams source) { 5280 super(source); 5281 } 5282 5283 /** 5284 * Sets the margins, in pixels. A call to {@link android.view.View#requestLayout()} needs 5285 * to be done so that the new margins are taken into account. Left and right margins may be 5286 * overriden by {@link android.view.View#requestLayout()} depending on layout direction. 5287 * 5288 * @param left the left margin size 5289 * @param top the top margin size 5290 * @param right the right margin size 5291 * @param bottom the bottom margin size 5292 * 5293 * @attr ref android.R.styleable#ViewGroup_MarginLayout_layout_marginLeft 5294 * @attr ref android.R.styleable#ViewGroup_MarginLayout_layout_marginTop 5295 * @attr ref android.R.styleable#ViewGroup_MarginLayout_layout_marginRight 5296 * @attr ref android.R.styleable#ViewGroup_MarginLayout_layout_marginBottom 5297 */ 5298 public void setMargins(int left, int top, int right, int bottom) { 5299 leftMargin = left; 5300 topMargin = top; 5301 rightMargin = right; 5302 bottomMargin = bottom; 5303 } 5304 5305 /** 5306 * Sets the relative margins, in pixels. A call to {@link android.view.View#requestLayout()} 5307 * needs to be done so that the new relative margins are taken into account. Left and right 5308 * margins may be overriden by {@link android.view.View#requestLayout()} depending on layout 5309 * direction. 5310 * 5311 * @param start the start margin size 5312 * @param top the top margin size 5313 * @param end the right margin size 5314 * @param bottom the bottom margin size 5315 * 5316 * @attr ref android.R.styleable#ViewGroup_MarginLayout_layout_marginStart 5317 * @attr ref android.R.styleable#ViewGroup_MarginLayout_layout_marginTop 5318 * @attr ref android.R.styleable#ViewGroup_MarginLayout_layout_marginEnd 5319 * @attr ref android.R.styleable#ViewGroup_MarginLayout_layout_marginBottom 5320 * 5321 * @hide 5322 */ 5323 public void setMarginsRelative(int start, int top, int end, int bottom) { 5324 startMargin = start; 5325 topMargin = top; 5326 endMargin = end; 5327 bottomMargin = bottom; 5328 } 5329 5330 /** 5331 * Returns the start margin in pixels. 5332 * 5333 * @attr ref android.R.styleable#ViewGroup_MarginLayout_layout_marginStart 5334 * 5335 * @return the start margin in pixels. 5336 */ 5337 public int getMarginStart() { 5338 return startMargin; 5339 } 5340 5341 /** 5342 * Returns the end margin in pixels. 5343 * 5344 * @attr ref android.R.styleable#ViewGroup_MarginLayout_layout_marginEnd 5345 * 5346 * @return the end margin in pixels. 5347 */ 5348 public int getMarginEnd() { 5349 return endMargin; 5350 } 5351 5352 /** 5353 * Check if margins are relative. 5354 * 5355 * @attr ref android.R.styleable#ViewGroup_MarginLayout_layout_marginStart 5356 * @attr ref android.R.styleable#ViewGroup_MarginLayout_layout_marginEnd 5357 * 5358 * @return true if either marginStart or marginEnd has been set 5359 */ 5360 public boolean isMarginRelative() { 5361 return (startMargin != DEFAULT_RELATIVE) || (endMargin != DEFAULT_RELATIVE); 5362 } 5363 5364 /** 5365 * This will be called by {@link android.view.View#requestLayout()}. Left and Right margins 5366 * maybe overriden depending on layout direction. 5367 * 5368 * @hide 5369 */ 5370 @Override 5371 protected void resolveWithDirection(int layoutDirection) { 5372 switch(layoutDirection) { 5373 case View.LAYOUT_DIRECTION_RTL: 5374 leftMargin = (endMargin > DEFAULT_RELATIVE) ? endMargin : leftMargin; 5375 rightMargin = (startMargin > DEFAULT_RELATIVE) ? startMargin : rightMargin; 5376 break; 5377 case View.LAYOUT_DIRECTION_LTR: 5378 default: 5379 leftMargin = (startMargin > DEFAULT_RELATIVE) ? startMargin : leftMargin; 5380 rightMargin = (endMargin > DEFAULT_RELATIVE) ? endMargin : rightMargin; 5381 break; 5382 } 5383 } 5384 } 5385 5386 /* Describes a touched view and the ids of the pointers that it has captured. 5387 * 5388 * This code assumes that pointer ids are always in the range 0..31 such that 5389 * it can use a bitfield to track which pointer ids are present. 5390 * As it happens, the lower layers of the input dispatch pipeline also use the 5391 * same trick so the assumption should be safe here... 5392 */ 5393 private static final class TouchTarget { 5394 private static final int MAX_RECYCLED = 32; 5395 private static final Object sRecycleLock = new Object(); 5396 private static TouchTarget sRecycleBin; 5397 private static int sRecycledCount; 5398 5399 public static final int ALL_POINTER_IDS = -1; // all ones 5400 5401 // The touched child view. 5402 public View child; 5403 5404 // The combined bit mask of pointer ids for all pointers captured by the target. 5405 public int pointerIdBits; 5406 5407 // The next target in the target list. 5408 public TouchTarget next; 5409 5410 private TouchTarget() { 5411 } 5412 5413 public static TouchTarget obtain(View child, int pointerIdBits) { 5414 final TouchTarget target; 5415 synchronized (sRecycleLock) { 5416 if (sRecycleBin == null) { 5417 target = new TouchTarget(); 5418 } else { 5419 target = sRecycleBin; 5420 sRecycleBin = target.next; 5421 sRecycledCount--; 5422 target.next = null; 5423 } 5424 } 5425 target.child = child; 5426 target.pointerIdBits = pointerIdBits; 5427 return target; 5428 } 5429 5430 public void recycle() { 5431 synchronized (sRecycleLock) { 5432 if (sRecycledCount < MAX_RECYCLED) { 5433 next = sRecycleBin; 5434 sRecycleBin = this; 5435 sRecycledCount += 1; 5436 } else { 5437 next = null; 5438 } 5439 child = null; 5440 } 5441 } 5442 } 5443 5444 /* Describes a hovered view. */ 5445 private static final class HoverTarget { 5446 private static final int MAX_RECYCLED = 32; 5447 private static final Object sRecycleLock = new Object(); 5448 private static HoverTarget sRecycleBin; 5449 private static int sRecycledCount; 5450 5451 // The hovered child view. 5452 public View child; 5453 5454 // The next target in the target list. 5455 public HoverTarget next; 5456 5457 private HoverTarget() { 5458 } 5459 5460 public static HoverTarget obtain(View child) { 5461 final HoverTarget target; 5462 synchronized (sRecycleLock) { 5463 if (sRecycleBin == null) { 5464 target = new HoverTarget(); 5465 } else { 5466 target = sRecycleBin; 5467 sRecycleBin = target.next; 5468 sRecycledCount--; 5469 target.next = null; 5470 } 5471 } 5472 target.child = child; 5473 return target; 5474 } 5475 5476 public void recycle() { 5477 synchronized (sRecycleLock) { 5478 if (sRecycledCount < MAX_RECYCLED) { 5479 next = sRecycleBin; 5480 sRecycleBin = this; 5481 sRecycledCount += 1; 5482 } else { 5483 next = null; 5484 } 5485 child = null; 5486 } 5487 } 5488 } 5489} 5490