ViewGroup.java revision e36d6e277e49475076b7872d36ea6a5c5b996e9d
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 com.android.internal.R; 20 21import android.content.Context; 22import android.content.res.Configuration; 23import android.content.res.TypedArray; 24import android.graphics.Bitmap; 25import android.graphics.Canvas; 26import android.graphics.Paint; 27import android.graphics.Rect; 28import android.graphics.RectF; 29import android.graphics.Region; 30import android.os.Parcelable; 31import android.os.SystemClock; 32import android.util.AttributeSet; 33import android.util.Config; 34import android.util.EventLog; 35import android.util.Log; 36import android.util.SparseArray; 37import android.view.accessibility.AccessibilityEvent; 38import android.view.animation.Animation; 39import android.view.animation.AnimationUtils; 40import android.view.animation.LayoutAnimationController; 41import android.view.animation.Transformation; 42 43import java.util.ArrayList; 44 45/** 46 * <p> 47 * A <code>ViewGroup</code> is a special view that can contain other views 48 * (called children.) The view group is the base class for layouts and views 49 * containers. This class also defines the 50 * {@link android.view.ViewGroup.LayoutParams} class which serves as the base 51 * class for layouts parameters. 52 * </p> 53 * 54 * <p> 55 * Also see {@link LayoutParams} for layout attributes. 56 * </p> 57 * 58 * @attr ref android.R.styleable#ViewGroup_clipChildren 59 * @attr ref android.R.styleable#ViewGroup_clipToPadding 60 * @attr ref android.R.styleable#ViewGroup_layoutAnimation 61 * @attr ref android.R.styleable#ViewGroup_animationCache 62 * @attr ref android.R.styleable#ViewGroup_persistentDrawingCache 63 * @attr ref android.R.styleable#ViewGroup_alwaysDrawnWithCache 64 * @attr ref android.R.styleable#ViewGroup_addStatesFromChildren 65 * @attr ref android.R.styleable#ViewGroup_descendantFocusability 66 */ 67public abstract class ViewGroup extends View implements ViewParent, ViewManager { 68 private static final boolean DBG = false; 69 70 /** 71 * Views which have been hidden or removed which need to be animated on 72 * their way out. 73 * This field should be made private, so it is hidden from the SDK. 74 * {@hide} 75 */ 76 protected ArrayList<View> mDisappearingChildren; 77 78 /** 79 * Listener used to propagate events indicating when children are added 80 * and/or removed from a view group. 81 * This field should be made private, so it is hidden from the SDK. 82 * {@hide} 83 */ 84 protected OnHierarchyChangeListener mOnHierarchyChangeListener; 85 86 // The view contained within this ViewGroup that has or contains focus. 87 private View mFocused; 88 89 // The current transformation to apply on the child being drawn 90 private Transformation mChildTransformation; 91 private RectF mInvalidateRegion; 92 93 // Target of Motion events 94 private View mMotionTarget; 95 private final Rect mTempRect = new Rect(); 96 97 // Layout animation 98 private LayoutAnimationController mLayoutAnimationController; 99 private Animation.AnimationListener mAnimationListener; 100 101 /** 102 * Internal flags. 103 * 104 * This field should be made private, so it is hidden from the SDK. 105 * {@hide} 106 */ 107 protected int mGroupFlags; 108 109 // When set, ViewGroup invalidates only the child's rectangle 110 // Set by default 111 private static final int FLAG_CLIP_CHILDREN = 0x1; 112 113 // When set, ViewGroup excludes the padding area from the invalidate rectangle 114 // Set by default 115 private static final int FLAG_CLIP_TO_PADDING = 0x2; 116 117 // When set, dispatchDraw() will invoke invalidate(); this is set by drawChild() when 118 // a child needs to be invalidated and FLAG_OPTIMIZE_INVALIDATE is set 119 private static final int FLAG_INVALIDATE_REQUIRED = 0x4; 120 121 // When set, dispatchDraw() will run the layout animation and unset the flag 122 private static final int FLAG_RUN_ANIMATION = 0x8; 123 124 // When set, there is either no layout animation on the ViewGroup or the layout 125 // animation is over 126 // Set by default 127 private static final int FLAG_ANIMATION_DONE = 0x10; 128 129 // If set, this ViewGroup has padding; if unset there is no padding and we don't need 130 // to clip it, even if FLAG_CLIP_TO_PADDING is set 131 private static final int FLAG_PADDING_NOT_NULL = 0x20; 132 133 // When set, this ViewGroup caches its children in a Bitmap before starting a layout animation 134 // Set by default 135 private static final int FLAG_ANIMATION_CACHE = 0x40; 136 137 // When set, this ViewGroup converts calls to invalidate(Rect) to invalidate() during a 138 // layout animation; this avoid clobbering the hierarchy 139 // Automatically set when the layout animation starts, depending on the animation's 140 // characteristics 141 private static final int FLAG_OPTIMIZE_INVALIDATE = 0x80; 142 143 // When set, the next call to drawChild() will clear mChildTransformation's matrix 144 private static final int FLAG_CLEAR_TRANSFORMATION = 0x100; 145 146 // When set, this ViewGroup invokes mAnimationListener.onAnimationEnd() and removes 147 // the children's Bitmap caches if necessary 148 // This flag is set when the layout animation is over (after FLAG_ANIMATION_DONE is set) 149 private static final int FLAG_NOTIFY_ANIMATION_LISTENER = 0x200; 150 151 /** 152 * When set, the drawing method will call {@link #getChildDrawingOrder(int, int)} 153 * to get the index of the child to draw for that iteration. 154 * 155 * @hide 156 */ 157 protected static final int FLAG_USE_CHILD_DRAWING_ORDER = 0x400; 158 159 /** 160 * When set, this ViewGroup supports static transformations on children; this causes 161 * {@link #getChildStaticTransformation(View, android.view.animation.Transformation)} to be 162 * invoked when a child is drawn. 163 * 164 * Any subclass overriding 165 * {@link #getChildStaticTransformation(View, android.view.animation.Transformation)} should 166 * set this flags in {@link #mGroupFlags}. 167 * 168 * {@hide} 169 */ 170 protected static final int FLAG_SUPPORT_STATIC_TRANSFORMATIONS = 0x800; 171 172 // When the previous drawChild() invocation used an alpha value that was lower than 173 // 1.0 and set it in mCachePaint 174 private static final int FLAG_ALPHA_LOWER_THAN_ONE = 0x1000; 175 176 /** 177 * When set, this ViewGroup's drawable states also include those 178 * of its children. 179 */ 180 private static final int FLAG_ADD_STATES_FROM_CHILDREN = 0x2000; 181 182 /** 183 * When set, this ViewGroup tries to always draw its children using their drawing cache. 184 */ 185 private static final int FLAG_ALWAYS_DRAWN_WITH_CACHE = 0x4000; 186 187 /** 188 * When set, and if FLAG_ALWAYS_DRAWN_WITH_CACHE is not set, this ViewGroup will try to 189 * draw its children with their drawing cache. 190 */ 191 private static final int FLAG_CHILDREN_DRAWN_WITH_CACHE = 0x8000; 192 193 /** 194 * When set, this group will go through its list of children to notify them of 195 * any drawable state change. 196 */ 197 private static final int FLAG_NOTIFY_CHILDREN_ON_DRAWABLE_STATE_CHANGE = 0x10000; 198 199 private static final int FLAG_MASK_FOCUSABILITY = 0x60000; 200 201 /** 202 * This view will get focus before any of its descendants. 203 */ 204 public static final int FOCUS_BEFORE_DESCENDANTS = 0x20000; 205 206 /** 207 * This view will get focus only if none of its descendants want it. 208 */ 209 public static final int FOCUS_AFTER_DESCENDANTS = 0x40000; 210 211 /** 212 * This view will block any of its descendants from getting focus, even 213 * if they are focusable. 214 */ 215 public static final int FOCUS_BLOCK_DESCENDANTS = 0x60000; 216 217 /** 218 * Used to map between enum in attrubutes and flag values. 219 */ 220 private static final int[] DESCENDANT_FOCUSABILITY_FLAGS = 221 {FOCUS_BEFORE_DESCENDANTS, FOCUS_AFTER_DESCENDANTS, 222 FOCUS_BLOCK_DESCENDANTS}; 223 224 /** 225 * When set, this ViewGroup should not intercept touch events. 226 */ 227 private static final int FLAG_DISALLOW_INTERCEPT = 0x80000; 228 229 /** 230 * Indicates which types of drawing caches are to be kept in memory. 231 * This field should be made private, so it is hidden from the SDK. 232 * {@hide} 233 */ 234 protected int mPersistentDrawingCache; 235 236 /** 237 * Used to indicate that no drawing cache should be kept in memory. 238 */ 239 public static final int PERSISTENT_NO_CACHE = 0x0; 240 241 /** 242 * Used to indicate that the animation drawing cache should be kept in memory. 243 */ 244 public static final int PERSISTENT_ANIMATION_CACHE = 0x1; 245 246 /** 247 * Used to indicate that the scrolling drawing cache should be kept in memory. 248 */ 249 public static final int PERSISTENT_SCROLLING_CACHE = 0x2; 250 251 /** 252 * Used to indicate that all drawing caches should be kept in memory. 253 */ 254 public static final int PERSISTENT_ALL_CACHES = 0x3; 255 256 /** 257 * We clip to padding when FLAG_CLIP_TO_PADDING and FLAG_PADDING_NOT_NULL 258 * are set at the same time. 259 */ 260 protected static final int CLIP_TO_PADDING_MASK = FLAG_CLIP_TO_PADDING | FLAG_PADDING_NOT_NULL; 261 262 // Index of the child's left position in the mLocation array 263 private static final int CHILD_LEFT_INDEX = 0; 264 // Index of the child's top position in the mLocation array 265 private static final int CHILD_TOP_INDEX = 1; 266 267 // Child views of this ViewGroup 268 private View[] mChildren; 269 // Number of valid children in the mChildren array, the rest should be null or not 270 // considered as children 271 private int mChildrenCount; 272 273 private static final int ARRAY_INITIAL_CAPACITY = 12; 274 private static final int ARRAY_CAPACITY_INCREMENT = 12; 275 276 // Used to draw cached views 277 private final Paint mCachePaint = new Paint(); 278 279 public ViewGroup(Context context) { 280 super(context); 281 initViewGroup(); 282 } 283 284 public ViewGroup(Context context, AttributeSet attrs) { 285 super(context, attrs); 286 initViewGroup(); 287 initFromAttributes(context, attrs); 288 } 289 290 public ViewGroup(Context context, AttributeSet attrs, int defStyle) { 291 super(context, attrs, defStyle); 292 initViewGroup(); 293 initFromAttributes(context, attrs); 294 } 295 296 private void initViewGroup() { 297 // ViewGroup doesn't draw by default 298 setFlags(WILL_NOT_DRAW, DRAW_MASK); 299 mGroupFlags |= FLAG_CLIP_CHILDREN; 300 mGroupFlags |= FLAG_CLIP_TO_PADDING; 301 mGroupFlags |= FLAG_ANIMATION_DONE; 302 mGroupFlags |= FLAG_ANIMATION_CACHE; 303 mGroupFlags |= FLAG_ALWAYS_DRAWN_WITH_CACHE; 304 305 setDescendantFocusability(FOCUS_BEFORE_DESCENDANTS); 306 307 mChildren = new View[ARRAY_INITIAL_CAPACITY]; 308 mChildrenCount = 0; 309 310 mCachePaint.setDither(false); 311 312 mPersistentDrawingCache = PERSISTENT_SCROLLING_CACHE; 313 } 314 315 private void initFromAttributes(Context context, AttributeSet attrs) { 316 TypedArray a = context.obtainStyledAttributes(attrs, 317 R.styleable.ViewGroup); 318 319 final int N = a.getIndexCount(); 320 for (int i = 0; i < N; i++) { 321 int attr = a.getIndex(i); 322 switch (attr) { 323 case R.styleable.ViewGroup_clipChildren: 324 setClipChildren(a.getBoolean(attr, true)); 325 break; 326 case R.styleable.ViewGroup_clipToPadding: 327 setClipToPadding(a.getBoolean(attr, true)); 328 break; 329 case R.styleable.ViewGroup_animationCache: 330 setAnimationCacheEnabled(a.getBoolean(attr, true)); 331 break; 332 case R.styleable.ViewGroup_persistentDrawingCache: 333 setPersistentDrawingCache(a.getInt(attr, PERSISTENT_SCROLLING_CACHE)); 334 break; 335 case R.styleable.ViewGroup_addStatesFromChildren: 336 setAddStatesFromChildren(a.getBoolean(attr, false)); 337 break; 338 case R.styleable.ViewGroup_alwaysDrawnWithCache: 339 setAlwaysDrawnWithCacheEnabled(a.getBoolean(attr, true)); 340 break; 341 case R.styleable.ViewGroup_layoutAnimation: 342 int id = a.getResourceId(attr, -1); 343 if (id > 0) { 344 setLayoutAnimation(AnimationUtils.loadLayoutAnimation(mContext, id)); 345 } 346 break; 347 case R.styleable.ViewGroup_descendantFocusability: 348 setDescendantFocusability(DESCENDANT_FOCUSABILITY_FLAGS[a.getInt(attr, 0)]); 349 break; 350 } 351 } 352 353 a.recycle(); 354 } 355 356 /** 357 * Gets the descendant focusability of this view group. The descendant 358 * focusability defines the relationship between this view group and its 359 * descendants when looking for a view to take focus in 360 * {@link #requestFocus(int, android.graphics.Rect)}. 361 * 362 * @return one of {@link #FOCUS_BEFORE_DESCENDANTS}, {@link #FOCUS_AFTER_DESCENDANTS}, 363 * {@link #FOCUS_BLOCK_DESCENDANTS}. 364 */ 365 @ViewDebug.ExportedProperty(mapping = { 366 @ViewDebug.IntToString(from = FOCUS_BEFORE_DESCENDANTS, to = "FOCUS_BEFORE_DESCENDANTS"), 367 @ViewDebug.IntToString(from = FOCUS_AFTER_DESCENDANTS, to = "FOCUS_AFTER_DESCENDANTS"), 368 @ViewDebug.IntToString(from = FOCUS_BLOCK_DESCENDANTS, to = "FOCUS_BLOCK_DESCENDANTS") 369 }) 370 public int getDescendantFocusability() { 371 return mGroupFlags & FLAG_MASK_FOCUSABILITY; 372 } 373 374 /** 375 * Set the descendant focusability of this view group. This defines the relationship 376 * between this view group and its descendants when looking for a view to 377 * take focus in {@link #requestFocus(int, android.graphics.Rect)}. 378 * 379 * @param focusability one of {@link #FOCUS_BEFORE_DESCENDANTS}, {@link #FOCUS_AFTER_DESCENDANTS}, 380 * {@link #FOCUS_BLOCK_DESCENDANTS}. 381 */ 382 public void setDescendantFocusability(int focusability) { 383 switch (focusability) { 384 case FOCUS_BEFORE_DESCENDANTS: 385 case FOCUS_AFTER_DESCENDANTS: 386 case FOCUS_BLOCK_DESCENDANTS: 387 break; 388 default: 389 throw new IllegalArgumentException("must be one of FOCUS_BEFORE_DESCENDANTS, " 390 + "FOCUS_AFTER_DESCENDANTS, FOCUS_BLOCK_DESCENDANTS"); 391 } 392 mGroupFlags &= ~FLAG_MASK_FOCUSABILITY; 393 mGroupFlags |= (focusability & FLAG_MASK_FOCUSABILITY); 394 } 395 396 /** 397 * {@inheritDoc} 398 */ 399 @Override 400 void handleFocusGainInternal(int direction, Rect previouslyFocusedRect) { 401 if (mFocused != null) { 402 mFocused.unFocus(); 403 mFocused = null; 404 } 405 super.handleFocusGainInternal(direction, previouslyFocusedRect); 406 } 407 408 /** 409 * {@inheritDoc} 410 */ 411 public void requestChildFocus(View child, View focused) { 412 if (DBG) { 413 System.out.println(this + " requestChildFocus()"); 414 } 415 if (getDescendantFocusability() == FOCUS_BLOCK_DESCENDANTS) { 416 return; 417 } 418 419 // Unfocus us, if necessary 420 super.unFocus(); 421 422 // We had a previous notion of who had focus. Clear it. 423 if (mFocused != child) { 424 if (mFocused != null) { 425 mFocused.unFocus(); 426 } 427 428 mFocused = child; 429 } 430 if (mParent != null) { 431 mParent.requestChildFocus(this, focused); 432 } 433 } 434 435 /** 436 * {@inheritDoc} 437 */ 438 public void focusableViewAvailable(View v) { 439 if (mParent != null 440 // shortcut: don't report a new focusable view if we block our descendants from 441 // getting focus 442 && (getDescendantFocusability() != FOCUS_BLOCK_DESCENDANTS) 443 // shortcut: don't report a new focusable view if we already are focused 444 // (and we don't prefer our descendants) 445 // 446 // note: knowing that mFocused is non-null is not a good enough reason 447 // to break the traversal since in that case we'd actually have to find 448 // the focused view and make sure it wasn't FOCUS_AFTER_DESCENDANTS and 449 // an ancestor of v; this will get checked for at ViewRoot 450 && !(isFocused() && getDescendantFocusability() != FOCUS_AFTER_DESCENDANTS)) { 451 mParent.focusableViewAvailable(v); 452 } 453 } 454 455 /** 456 * {@inheritDoc} 457 */ 458 public boolean showContextMenuForChild(View originalView) { 459 return mParent != null && mParent.showContextMenuForChild(originalView); 460 } 461 462 /** 463 * Find the nearest view in the specified direction that wants to take 464 * focus. 465 * 466 * @param focused The view that currently has focus 467 * @param direction One of FOCUS_UP, FOCUS_DOWN, FOCUS_LEFT, and 468 * FOCUS_RIGHT, or 0 for not applicable. 469 */ 470 public View focusSearch(View focused, int direction) { 471 if (isRootNamespace()) { 472 // root namespace means we should consider ourselves the top of the 473 // tree for focus searching; otherwise we could be focus searching 474 // into other tabs. see LocalActivityManager and TabHost for more info 475 return FocusFinder.getInstance().findNextFocus(this, focused, direction); 476 } else if (mParent != null) { 477 return mParent.focusSearch(focused, direction); 478 } 479 return null; 480 } 481 482 /** 483 * {@inheritDoc} 484 */ 485 public boolean requestChildRectangleOnScreen(View child, Rect rectangle, boolean immediate) { 486 return false; 487 } 488 489 /** 490 * {@inheritDoc} 491 */ 492 @Override 493 public boolean dispatchUnhandledMove(View focused, int direction) { 494 return mFocused != null && 495 mFocused.dispatchUnhandledMove(focused, direction); 496 } 497 498 /** 499 * {@inheritDoc} 500 */ 501 public void clearChildFocus(View child) { 502 if (DBG) { 503 System.out.println(this + " clearChildFocus()"); 504 } 505 506 mFocused = null; 507 if (mParent != null) { 508 mParent.clearChildFocus(this); 509 } 510 } 511 512 /** 513 * {@inheritDoc} 514 */ 515 @Override 516 public void clearFocus() { 517 super.clearFocus(); 518 519 // clear any child focus if it exists 520 if (mFocused != null) { 521 mFocused.clearFocus(); 522 } 523 } 524 525 /** 526 * {@inheritDoc} 527 */ 528 @Override 529 void unFocus() { 530 if (DBG) { 531 System.out.println(this + " unFocus()"); 532 } 533 534 super.unFocus(); 535 if (mFocused != null) { 536 mFocused.unFocus(); 537 } 538 mFocused = null; 539 } 540 541 /** 542 * Returns the focused child of this view, if any. The child may have focus 543 * or contain focus. 544 * 545 * @return the focused child or null. 546 */ 547 public View getFocusedChild() { 548 return mFocused; 549 } 550 551 /** 552 * Returns true if this view has or contains focus 553 * 554 * @return true if this view has or contains focus 555 */ 556 @Override 557 public boolean hasFocus() { 558 return (mPrivateFlags & FOCUSED) != 0 || mFocused != null; 559 } 560 561 /* 562 * (non-Javadoc) 563 * 564 * @see android.view.View#findFocus() 565 */ 566 @Override 567 public View findFocus() { 568 if (DBG) { 569 System.out.println("Find focus in " + this + ": flags=" 570 + isFocused() + ", child=" + mFocused); 571 } 572 573 if (isFocused()) { 574 return this; 575 } 576 577 if (mFocused != null) { 578 return mFocused.findFocus(); 579 } 580 return null; 581 } 582 583 /** 584 * {@inheritDoc} 585 */ 586 @Override 587 public boolean hasFocusable() { 588 if ((mViewFlags & VISIBILITY_MASK) != VISIBLE) { 589 return false; 590 } 591 592 if (isFocusable()) { 593 return true; 594 } 595 596 final int descendantFocusability = getDescendantFocusability(); 597 if (descendantFocusability != FOCUS_BLOCK_DESCENDANTS) { 598 final int count = mChildrenCount; 599 final View[] children = mChildren; 600 601 for (int i = 0; i < count; i++) { 602 final View child = children[i]; 603 if (child.hasFocusable()) { 604 return true; 605 } 606 } 607 } 608 609 return false; 610 } 611 612 /** 613 * {@inheritDoc} 614 */ 615 @Override 616 public void addFocusables(ArrayList<View> views, int direction) { 617 addFocusables(views, direction, FOCUSABLES_TOUCH_MODE); 618 } 619 620 /** 621 * {@inheritDoc} 622 */ 623 @Override 624 public void addFocusables(ArrayList<View> views, int direction, int focusableMode) { 625 final int focusableCount = views.size(); 626 627 final int descendantFocusability = getDescendantFocusability(); 628 629 if (descendantFocusability != FOCUS_BLOCK_DESCENDANTS) { 630 final int count = mChildrenCount; 631 final View[] children = mChildren; 632 633 for (int i = 0; i < count; i++) { 634 final View child = children[i]; 635 if ((child.mViewFlags & VISIBILITY_MASK) == VISIBLE) { 636 child.addFocusables(views, direction, focusableMode); 637 } 638 } 639 } 640 641 // we add ourselves (if focusable) in all cases except for when we are 642 // FOCUS_AFTER_DESCENDANTS and there are some descendants focusable. this is 643 // to avoid the focus search finding layouts when a more precise search 644 // among the focusable children would be more interesting. 645 if ( 646 descendantFocusability != FOCUS_AFTER_DESCENDANTS || 647 // No focusable descendants 648 (focusableCount == views.size())) { 649 super.addFocusables(views, direction, focusableMode); 650 } 651 } 652 653 /** 654 * {@inheritDoc} 655 */ 656 @Override 657 public void dispatchWindowFocusChanged(boolean hasFocus) { 658 super.dispatchWindowFocusChanged(hasFocus); 659 final int count = mChildrenCount; 660 final View[] children = mChildren; 661 for (int i = 0; i < count; i++) { 662 children[i].dispatchWindowFocusChanged(hasFocus); 663 } 664 } 665 666 /** 667 * {@inheritDoc} 668 */ 669 @Override 670 public void addTouchables(ArrayList<View> views) { 671 super.addTouchables(views); 672 673 final int count = mChildrenCount; 674 final View[] children = mChildren; 675 676 for (int i = 0; i < count; i++) { 677 final View child = children[i]; 678 if ((child.mViewFlags & VISIBILITY_MASK) == VISIBLE) { 679 child.addTouchables(views); 680 } 681 } 682 } 683 684 /** 685 * {@inheritDoc} 686 */ 687 @Override 688 public void dispatchDisplayHint(int hint) { 689 super.dispatchDisplayHint(hint); 690 final int count = mChildrenCount; 691 final View[] children = mChildren; 692 for (int i = 0; i < count; i++) { 693 children[i].dispatchDisplayHint(hint); 694 } 695 } 696 697 /** 698 * {@inheritDoc} 699 */ 700 @Override 701 protected void dispatchVisibilityChanged(View changedView, int visibility) { 702 super.dispatchVisibilityChanged(changedView, visibility); 703 final int count = mChildrenCount; 704 final View[] children = mChildren; 705 for (int i = 0; i < count; i++) { 706 children[i].dispatchVisibilityChanged(changedView, visibility); 707 } 708 } 709 710 /** 711 * {@inheritDoc} 712 */ 713 @Override 714 public void dispatchWindowVisibilityChanged(int visibility) { 715 super.dispatchWindowVisibilityChanged(visibility); 716 final int count = mChildrenCount; 717 final View[] children = mChildren; 718 for (int i = 0; i < count; i++) { 719 children[i].dispatchWindowVisibilityChanged(visibility); 720 } 721 } 722 723 /** 724 * {@inheritDoc} 725 */ 726 @Override 727 public void dispatchConfigurationChanged(Configuration newConfig) { 728 super.dispatchConfigurationChanged(newConfig); 729 final int count = mChildrenCount; 730 final View[] children = mChildren; 731 for (int i = 0; i < count; i++) { 732 children[i].dispatchConfigurationChanged(newConfig); 733 } 734 } 735 736 /** 737 * {@inheritDoc} 738 */ 739 public void recomputeViewAttributes(View child) { 740 ViewParent parent = mParent; 741 if (parent != null) parent.recomputeViewAttributes(this); 742 } 743 744 @Override 745 void dispatchCollectViewAttributes(int visibility) { 746 visibility |= mViewFlags&VISIBILITY_MASK; 747 super.dispatchCollectViewAttributes(visibility); 748 final int count = mChildrenCount; 749 final View[] children = mChildren; 750 for (int i = 0; i < count; i++) { 751 children[i].dispatchCollectViewAttributes(visibility); 752 } 753 } 754 755 /** 756 * {@inheritDoc} 757 */ 758 public void bringChildToFront(View child) { 759 int index = indexOfChild(child); 760 if (index >= 0) { 761 removeFromArray(index); 762 addInArray(child, mChildrenCount); 763 child.mParent = this; 764 } 765 } 766 767 /** 768 * {@inheritDoc} 769 */ 770 @Override 771 public boolean dispatchKeyEventPreIme(KeyEvent event) { 772 if ((mPrivateFlags & (FOCUSED | HAS_BOUNDS)) == (FOCUSED | HAS_BOUNDS)) { 773 return super.dispatchKeyEventPreIme(event); 774 } else if (mFocused != null && (mFocused.mPrivateFlags & HAS_BOUNDS) == HAS_BOUNDS) { 775 return mFocused.dispatchKeyEventPreIme(event); 776 } 777 return false; 778 } 779 780 /** 781 * {@inheritDoc} 782 */ 783 @Override 784 public boolean dispatchKeyEvent(KeyEvent event) { 785 if ((mPrivateFlags & (FOCUSED | HAS_BOUNDS)) == (FOCUSED | HAS_BOUNDS)) { 786 return super.dispatchKeyEvent(event); 787 } else if (mFocused != null && (mFocused.mPrivateFlags & HAS_BOUNDS) == HAS_BOUNDS) { 788 return mFocused.dispatchKeyEvent(event); 789 } 790 return false; 791 } 792 793 /** 794 * {@inheritDoc} 795 */ 796 @Override 797 public boolean dispatchKeyShortcutEvent(KeyEvent event) { 798 if ((mPrivateFlags & (FOCUSED | HAS_BOUNDS)) == (FOCUSED | HAS_BOUNDS)) { 799 return super.dispatchKeyShortcutEvent(event); 800 } else if (mFocused != null && (mFocused.mPrivateFlags & HAS_BOUNDS) == HAS_BOUNDS) { 801 return mFocused.dispatchKeyShortcutEvent(event); 802 } 803 return false; 804 } 805 806 /** 807 * {@inheritDoc} 808 */ 809 @Override 810 public boolean dispatchTrackballEvent(MotionEvent event) { 811 if ((mPrivateFlags & (FOCUSED | HAS_BOUNDS)) == (FOCUSED | HAS_BOUNDS)) { 812 return super.dispatchTrackballEvent(event); 813 } else if (mFocused != null && (mFocused.mPrivateFlags & HAS_BOUNDS) == HAS_BOUNDS) { 814 return mFocused.dispatchTrackballEvent(event); 815 } 816 return false; 817 } 818 819 /** 820 * {@inheritDoc} 821 */ 822 @Override 823 public boolean dispatchTouchEvent(MotionEvent ev) { 824 final int action = ev.getAction(); 825 final float xf = ev.getX(); 826 final float yf = ev.getY(); 827 final float scrolledXFloat = xf + mScrollX; 828 final float scrolledYFloat = yf + mScrollY; 829 final Rect frame = mTempRect; 830 831 boolean disallowIntercept = (mGroupFlags & FLAG_DISALLOW_INTERCEPT) != 0; 832 833 if (action == MotionEvent.ACTION_DOWN) { 834 if (mMotionTarget != null) { 835 // this is weird, we got a pen down, but we thought it was 836 // already down! 837 // XXX: We should probably send an ACTION_UP to the current 838 // target. 839 mMotionTarget = null; 840 } 841 // If we're disallowing intercept or if we're allowing and we didn't 842 // intercept 843 if (disallowIntercept || !onInterceptTouchEvent(ev)) { 844 // reset this event's action (just to protect ourselves) 845 ev.setAction(MotionEvent.ACTION_DOWN); 846 // We know we want to dispatch the event down, find a child 847 // who can handle it, start with the front-most child. 848 final int scrolledXInt = (int) scrolledXFloat; 849 final int scrolledYInt = (int) scrolledYFloat; 850 final View[] children = mChildren; 851 final int count = mChildrenCount; 852 for (int i = count - 1; i >= 0; i--) { 853 final View child = children[i]; 854 if ((child.mViewFlags & VISIBILITY_MASK) == VISIBLE 855 || child.getAnimation() != null) { 856 child.getHitRect(frame); 857 if (frame.contains(scrolledXInt, scrolledYInt)) { 858 // offset the event to the view's coordinate system 859 final float xc = scrolledXFloat - child.mLeft; 860 final float yc = scrolledYFloat - child.mTop; 861 ev.setLocation(xc, yc); 862 if (child.dispatchTouchEvent(ev)) { 863 // Event handled, we have a target now. 864 mMotionTarget = child; 865 return true; 866 } 867 // The event didn't get handled, try the next view. 868 // Don't reset the event's location, it's not 869 // necessary here. 870 } 871 } 872 } 873 } 874 } 875 876 boolean isUpOrCancel = (action == MotionEvent.ACTION_UP) || 877 (action == MotionEvent.ACTION_CANCEL); 878 879 if (isUpOrCancel) { 880 // Note, we've already copied the previous state to our local 881 // variable, so this takes effect on the next event 882 mGroupFlags &= ~FLAG_DISALLOW_INTERCEPT; 883 } 884 885 // The event wasn't an ACTION_DOWN, dispatch it to our target if 886 // we have one. 887 final View target = mMotionTarget; 888 if (target == null) { 889 // We don't have a target, this means we're handling the 890 // event as a regular view. 891 ev.setLocation(xf, yf); 892 return super.dispatchTouchEvent(ev); 893 } 894 895 // if have a target, see if we're allowed to and want to intercept its 896 // events 897 if (!disallowIntercept && onInterceptTouchEvent(ev)) { 898 final float xc = scrolledXFloat - (float) target.mLeft; 899 final float yc = scrolledYFloat - (float) target.mTop; 900 ev.setAction(MotionEvent.ACTION_CANCEL); 901 ev.setLocation(xc, yc); 902 if (!target.dispatchTouchEvent(ev)) { 903 // target didn't handle ACTION_CANCEL. not much we can do 904 // but they should have. 905 } 906 // clear the target 907 mMotionTarget = null; 908 // Don't dispatch this event to our own view, because we already 909 // saw it when intercepting; we just want to give the following 910 // event to the normal onTouchEvent(). 911 return true; 912 } 913 914 if (isUpOrCancel) { 915 mMotionTarget = null; 916 } 917 918 // finally offset the event to the target's coordinate system and 919 // dispatch the event. 920 final float xc = scrolledXFloat - (float) target.mLeft; 921 final float yc = scrolledYFloat - (float) target.mTop; 922 ev.setLocation(xc, yc); 923 924 return target.dispatchTouchEvent(ev); 925 } 926 927 /** 928 * {@inheritDoc} 929 */ 930 public void requestDisallowInterceptTouchEvent(boolean disallowIntercept) { 931 932 if (disallowIntercept == ((mGroupFlags & FLAG_DISALLOW_INTERCEPT) != 0)) { 933 // We're already in this state, assume our ancestors are too 934 return; 935 } 936 937 if (disallowIntercept) { 938 mGroupFlags |= FLAG_DISALLOW_INTERCEPT; 939 } else { 940 mGroupFlags &= ~FLAG_DISALLOW_INTERCEPT; 941 } 942 943 // Pass it up to our parent 944 if (mParent != null) { 945 mParent.requestDisallowInterceptTouchEvent(disallowIntercept); 946 } 947 } 948 949 /** 950 * Implement this method to intercept all touch screen motion events. This 951 * allows you to watch events as they are dispatched to your children, and 952 * take ownership of the current gesture at any point. 953 * 954 * <p>Using this function takes some care, as it has a fairly complicated 955 * interaction with {@link View#onTouchEvent(MotionEvent) 956 * View.onTouchEvent(MotionEvent)}, and using it requires implementing 957 * that method as well as this one in the correct way. Events will be 958 * received in the following order: 959 * 960 * <ol> 961 * <li> You will receive the down event here. 962 * <li> The down event will be handled either by a child of this view 963 * group, or given to your own onTouchEvent() method to handle; this means 964 * you should implement onTouchEvent() to return true, so you will 965 * continue to see the rest of the gesture (instead of looking for 966 * a parent view to handle it). Also, by returning true from 967 * onTouchEvent(), you will not receive any following 968 * events in onInterceptTouchEvent() and all touch processing must 969 * happen in onTouchEvent() like normal. 970 * <li> For as long as you return false from this function, each following 971 * event (up to and including the final up) will be delivered first here 972 * and then to the target's onTouchEvent(). 973 * <li> If you return true from here, you will not receive any 974 * following events: the target view will receive the same event but 975 * with the action {@link MotionEvent#ACTION_CANCEL}, and all further 976 * events will be delivered to your onTouchEvent() method and no longer 977 * appear here. 978 * </ol> 979 * 980 * @param ev The motion event being dispatched down the hierarchy. 981 * @return Return true to steal motion events from the children and have 982 * them dispatched to this ViewGroup through onTouchEvent(). 983 * The current target will receive an ACTION_CANCEL event, and no further 984 * messages will be delivered here. 985 */ 986 public boolean onInterceptTouchEvent(MotionEvent ev) { 987 return false; 988 } 989 990 /** 991 * {@inheritDoc} 992 * 993 * Looks for a view to give focus to respecting the setting specified by 994 * {@link #getDescendantFocusability()}. 995 * 996 * Uses {@link #onRequestFocusInDescendants(int, android.graphics.Rect)} to 997 * find focus within the children of this group when appropriate. 998 * 999 * @see #FOCUS_BEFORE_DESCENDANTS 1000 * @see #FOCUS_AFTER_DESCENDANTS 1001 * @see #FOCUS_BLOCK_DESCENDANTS 1002 * @see #onRequestFocusInDescendants 1003 */ 1004 @Override 1005 public boolean requestFocus(int direction, Rect previouslyFocusedRect) { 1006 if (DBG) { 1007 System.out.println(this + " ViewGroup.requestFocus direction=" 1008 + direction); 1009 } 1010 int descendantFocusability = getDescendantFocusability(); 1011 1012 switch (descendantFocusability) { 1013 case FOCUS_BLOCK_DESCENDANTS: 1014 return super.requestFocus(direction, previouslyFocusedRect); 1015 case FOCUS_BEFORE_DESCENDANTS: { 1016 final boolean took = super.requestFocus(direction, previouslyFocusedRect); 1017 return took ? took : onRequestFocusInDescendants(direction, previouslyFocusedRect); 1018 } 1019 case FOCUS_AFTER_DESCENDANTS: { 1020 final boolean took = onRequestFocusInDescendants(direction, previouslyFocusedRect); 1021 return took ? took : super.requestFocus(direction, previouslyFocusedRect); 1022 } 1023 default: 1024 throw new IllegalStateException("descendant focusability must be " 1025 + "one of FOCUS_BEFORE_DESCENDANTS, FOCUS_AFTER_DESCENDANTS, FOCUS_BLOCK_DESCENDANTS " 1026 + "but is " + descendantFocusability); 1027 } 1028 } 1029 1030 /** 1031 * Look for a descendant to call {@link View#requestFocus} on. 1032 * Called by {@link ViewGroup#requestFocus(int, android.graphics.Rect)} 1033 * when it wants to request focus within its children. Override this to 1034 * customize how your {@link ViewGroup} requests focus within its children. 1035 * @param direction One of FOCUS_UP, FOCUS_DOWN, FOCUS_LEFT, and FOCUS_RIGHT 1036 * @param previouslyFocusedRect The rectangle (in this View's coordinate system) 1037 * to give a finer grained hint about where focus is coming from. May be null 1038 * if there is no hint. 1039 * @return Whether focus was taken. 1040 */ 1041 @SuppressWarnings({"ConstantConditions"}) 1042 protected boolean onRequestFocusInDescendants(int direction, 1043 Rect previouslyFocusedRect) { 1044 int index; 1045 int increment; 1046 int end; 1047 int count = mChildrenCount; 1048 if ((direction & FOCUS_FORWARD) != 0) { 1049 index = 0; 1050 increment = 1; 1051 end = count; 1052 } else { 1053 index = count - 1; 1054 increment = -1; 1055 end = -1; 1056 } 1057 final View[] children = mChildren; 1058 for (int i = index; i != end; i += increment) { 1059 View child = children[i]; 1060 if ((child.mViewFlags & VISIBILITY_MASK) == VISIBLE) { 1061 if (child.requestFocus(direction, previouslyFocusedRect)) { 1062 return true; 1063 } 1064 } 1065 } 1066 return false; 1067 } 1068 1069 /** 1070 * {@inheritDoc} 1071 */ 1072 @Override 1073 void dispatchAttachedToWindow(AttachInfo info, int visibility) { 1074 super.dispatchAttachedToWindow(info, visibility); 1075 visibility |= mViewFlags & VISIBILITY_MASK; 1076 final int count = mChildrenCount; 1077 final View[] children = mChildren; 1078 for (int i = 0; i < count; i++) { 1079 children[i].dispatchAttachedToWindow(info, visibility); 1080 } 1081 } 1082 1083 @Override 1084 public boolean dispatchPopulateAccessibilityEvent(AccessibilityEvent event) { 1085 boolean populated = false; 1086 for (int i = 0, count = getChildCount(); i < count; i++) { 1087 populated |= getChildAt(i).dispatchPopulateAccessibilityEvent(event); 1088 } 1089 return populated; 1090 } 1091 1092 /** 1093 * {@inheritDoc} 1094 */ 1095 @Override 1096 void dispatchDetachedFromWindow() { 1097 // If we still have a motion target, we are still in the process of 1098 // dispatching motion events to a child; we need to get rid of that 1099 // child to avoid dispatching events to it after the window is torn 1100 // down. To make sure we keep the child in a consistent state, we 1101 // first send it an ACTION_CANCEL motion event. 1102 if (mMotionTarget != null) { 1103 final long now = SystemClock.uptimeMillis(); 1104 final MotionEvent event = MotionEvent.obtain(now, now, 1105 MotionEvent.ACTION_CANCEL, 0.0f, 0.0f, 0); 1106 mMotionTarget.dispatchTouchEvent(event); 1107 event.recycle(); 1108 mMotionTarget = null; 1109 } 1110 1111 final int count = mChildrenCount; 1112 final View[] children = mChildren; 1113 for (int i = 0; i < count; i++) { 1114 children[i].dispatchDetachedFromWindow(); 1115 } 1116 super.dispatchDetachedFromWindow(); 1117 } 1118 1119 /** 1120 * {@inheritDoc} 1121 */ 1122 @Override 1123 public void setPadding(int left, int top, int right, int bottom) { 1124 super.setPadding(left, top, right, bottom); 1125 1126 if ((mPaddingLeft | mPaddingTop | mPaddingRight | mPaddingRight) != 0) { 1127 mGroupFlags |= FLAG_PADDING_NOT_NULL; 1128 } else { 1129 mGroupFlags &= ~FLAG_PADDING_NOT_NULL; 1130 } 1131 } 1132 1133 /** 1134 * {@inheritDoc} 1135 */ 1136 @Override 1137 protected void dispatchSaveInstanceState(SparseArray<Parcelable> container) { 1138 super.dispatchSaveInstanceState(container); 1139 final int count = mChildrenCount; 1140 final View[] children = mChildren; 1141 for (int i = 0; i < count; i++) { 1142 children[i].dispatchSaveInstanceState(container); 1143 } 1144 } 1145 1146 /** 1147 * Perform dispatching of a {@link #saveHierarchyState freeze()} to only this view, 1148 * not to its children. For use when overriding 1149 * {@link #dispatchSaveInstanceState dispatchFreeze()} to allow subclasses to freeze 1150 * their own state but not the state of their children. 1151 * 1152 * @param container the container 1153 */ 1154 protected void dispatchFreezeSelfOnly(SparseArray<Parcelable> container) { 1155 super.dispatchSaveInstanceState(container); 1156 } 1157 1158 /** 1159 * {@inheritDoc} 1160 */ 1161 @Override 1162 protected void dispatchRestoreInstanceState(SparseArray<Parcelable> container) { 1163 super.dispatchRestoreInstanceState(container); 1164 final int count = mChildrenCount; 1165 final View[] children = mChildren; 1166 for (int i = 0; i < count; i++) { 1167 children[i].dispatchRestoreInstanceState(container); 1168 } 1169 } 1170 1171 /** 1172 * Perform dispatching of a {@link #restoreHierarchyState thaw()} to only this view, 1173 * not to its children. For use when overriding 1174 * {@link #dispatchRestoreInstanceState dispatchThaw()} to allow subclasses to thaw 1175 * their own state but not the state of their children. 1176 * 1177 * @param container the container 1178 */ 1179 protected void dispatchThawSelfOnly(SparseArray<Parcelable> container) { 1180 super.dispatchRestoreInstanceState(container); 1181 } 1182 1183 /** 1184 * Enables or disables the drawing cache for each child of this view group. 1185 * 1186 * @param enabled true to enable the cache, false to dispose of it 1187 */ 1188 protected void setChildrenDrawingCacheEnabled(boolean enabled) { 1189 if (enabled || (mPersistentDrawingCache & PERSISTENT_ALL_CACHES) != PERSISTENT_ALL_CACHES) { 1190 final View[] children = mChildren; 1191 final int count = mChildrenCount; 1192 for (int i = 0; i < count; i++) { 1193 children[i].setDrawingCacheEnabled(enabled); 1194 } 1195 } 1196 } 1197 1198 @Override 1199 protected void onAnimationStart() { 1200 super.onAnimationStart(); 1201 1202 // When this ViewGroup's animation starts, build the cache for the children 1203 if ((mGroupFlags & FLAG_ANIMATION_CACHE) == FLAG_ANIMATION_CACHE) { 1204 final int count = mChildrenCount; 1205 final View[] children = mChildren; 1206 1207 for (int i = 0; i < count; i++) { 1208 final View child = children[i]; 1209 if ((child.mViewFlags & VISIBILITY_MASK) == VISIBLE) { 1210 child.setDrawingCacheEnabled(true); 1211 child.buildDrawingCache(true); 1212 } 1213 } 1214 1215 mGroupFlags |= FLAG_CHILDREN_DRAWN_WITH_CACHE; 1216 } 1217 } 1218 1219 @Override 1220 protected void onAnimationEnd() { 1221 super.onAnimationEnd(); 1222 1223 // When this ViewGroup's animation ends, destroy the cache of the children 1224 if ((mGroupFlags & FLAG_ANIMATION_CACHE) == FLAG_ANIMATION_CACHE) { 1225 mGroupFlags &= ~FLAG_CHILDREN_DRAWN_WITH_CACHE; 1226 1227 if ((mPersistentDrawingCache & PERSISTENT_ANIMATION_CACHE) == 0) { 1228 setChildrenDrawingCacheEnabled(false); 1229 } 1230 } 1231 } 1232 1233 /** 1234 * {@inheritDoc} 1235 */ 1236 @Override 1237 protected void dispatchDraw(Canvas canvas) { 1238 final int count = mChildrenCount; 1239 final View[] children = mChildren; 1240 int flags = mGroupFlags; 1241 1242 if ((flags & FLAG_RUN_ANIMATION) != 0 && canAnimate()) { 1243 final boolean cache = (mGroupFlags & FLAG_ANIMATION_CACHE) == FLAG_ANIMATION_CACHE; 1244 1245 for (int i = 0; i < count; i++) { 1246 final View child = children[i]; 1247 if ((child.mViewFlags & VISIBILITY_MASK) == VISIBLE) { 1248 final LayoutParams params = child.getLayoutParams(); 1249 attachLayoutAnimationParameters(child, params, i, count); 1250 bindLayoutAnimation(child); 1251 if (cache) { 1252 child.setDrawingCacheEnabled(true); 1253 child.buildDrawingCache(true); 1254 } 1255 } 1256 } 1257 1258 final LayoutAnimationController controller = mLayoutAnimationController; 1259 if (controller.willOverlap()) { 1260 mGroupFlags |= FLAG_OPTIMIZE_INVALIDATE; 1261 } 1262 1263 controller.start(); 1264 1265 mGroupFlags &= ~FLAG_RUN_ANIMATION; 1266 mGroupFlags &= ~FLAG_ANIMATION_DONE; 1267 1268 if (cache) { 1269 mGroupFlags |= FLAG_CHILDREN_DRAWN_WITH_CACHE; 1270 } 1271 1272 if (mAnimationListener != null) { 1273 mAnimationListener.onAnimationStart(controller.getAnimation()); 1274 } 1275 } 1276 1277 int saveCount = 0; 1278 final boolean clipToPadding = (flags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK; 1279 if (clipToPadding) { 1280 saveCount = canvas.save(); 1281 canvas.clipRect(mScrollX + mPaddingLeft, mScrollY + mPaddingTop, 1282 mScrollX + mRight - mLeft - mPaddingRight, 1283 mScrollY + mBottom - mTop - mPaddingBottom); 1284 1285 } 1286 1287 // We will draw our child's animation, let's reset the flag 1288 mPrivateFlags &= ~DRAW_ANIMATION; 1289 mGroupFlags &= ~FLAG_INVALIDATE_REQUIRED; 1290 1291 boolean more = false; 1292 final long drawingTime = getDrawingTime(); 1293 1294 if ((flags & FLAG_USE_CHILD_DRAWING_ORDER) == 0) { 1295 for (int i = 0; i < count; i++) { 1296 final View child = children[i]; 1297 if ((child.mViewFlags & VISIBILITY_MASK) == VISIBLE || child.getAnimation() != null) { 1298 more |= drawChild(canvas, child, drawingTime); 1299 } 1300 } 1301 } else { 1302 for (int i = 0; i < count; i++) { 1303 final View child = children[getChildDrawingOrder(count, i)]; 1304 if ((child.mViewFlags & VISIBILITY_MASK) == VISIBLE || child.getAnimation() != null) { 1305 more |= drawChild(canvas, child, drawingTime); 1306 } 1307 } 1308 } 1309 1310 // Draw any disappearing views that have animations 1311 if (mDisappearingChildren != null) { 1312 final ArrayList<View> disappearingChildren = mDisappearingChildren; 1313 final int disappearingCount = disappearingChildren.size() - 1; 1314 // Go backwards -- we may delete as animations finish 1315 for (int i = disappearingCount; i >= 0; i--) { 1316 final View child = disappearingChildren.get(i); 1317 more |= drawChild(canvas, child, drawingTime); 1318 } 1319 } 1320 1321 if (clipToPadding) { 1322 canvas.restoreToCount(saveCount); 1323 } 1324 1325 // mGroupFlags might have been updated by drawChild() 1326 flags = mGroupFlags; 1327 1328 if ((flags & FLAG_INVALIDATE_REQUIRED) == FLAG_INVALIDATE_REQUIRED) { 1329 invalidate(); 1330 } 1331 1332 if ((flags & FLAG_ANIMATION_DONE) == 0 && (flags & FLAG_NOTIFY_ANIMATION_LISTENER) == 0 && 1333 mLayoutAnimationController.isDone() && !more) { 1334 // We want to erase the drawing cache and notify the listener after the 1335 // next frame is drawn because one extra invalidate() is caused by 1336 // drawChild() after the animation is over 1337 mGroupFlags |= FLAG_NOTIFY_ANIMATION_LISTENER; 1338 final Runnable end = new Runnable() { 1339 public void run() { 1340 notifyAnimationListener(); 1341 } 1342 }; 1343 post(end); 1344 } 1345 } 1346 1347 /** 1348 * Returns the index of the child to draw for this iteration. Override this 1349 * if you want to change the drawing order of children. By default, it 1350 * returns i. 1351 * <p> 1352 * NOTE: In order for this method to be called, you must enable child ordering 1353 * first by calling {@link #setChildrenDrawingOrderEnabled(boolean)}. 1354 * 1355 * @param i The current iteration. 1356 * @return The index of the child to draw this iteration. 1357 * 1358 * @see #setChildrenDrawingOrderEnabled(boolean) 1359 * @see #isChildrenDrawingOrderEnabled() 1360 */ 1361 protected int getChildDrawingOrder(int childCount, int i) { 1362 return i; 1363 } 1364 1365 private void notifyAnimationListener() { 1366 mGroupFlags &= ~FLAG_NOTIFY_ANIMATION_LISTENER; 1367 mGroupFlags |= FLAG_ANIMATION_DONE; 1368 1369 if (mAnimationListener != null) { 1370 final Runnable end = new Runnable() { 1371 public void run() { 1372 mAnimationListener.onAnimationEnd(mLayoutAnimationController.getAnimation()); 1373 } 1374 }; 1375 post(end); 1376 } 1377 1378 if ((mGroupFlags & FLAG_ANIMATION_CACHE) == FLAG_ANIMATION_CACHE) { 1379 mGroupFlags &= ~FLAG_CHILDREN_DRAWN_WITH_CACHE; 1380 if ((mPersistentDrawingCache & PERSISTENT_ANIMATION_CACHE) == 0) { 1381 setChildrenDrawingCacheEnabled(false); 1382 } 1383 } 1384 1385 invalidate(); 1386 } 1387 1388 /** 1389 * Draw one child of this View Group. This method is responsible for getting 1390 * the canvas in the right state. This includes clipping, translating so 1391 * that the child's scrolled origin is at 0, 0, and applying any animation 1392 * transformations. 1393 * 1394 * @param canvas The canvas on which to draw the child 1395 * @param child Who to draw 1396 * @param drawingTime The time at which draw is occuring 1397 * @return True if an invalidate() was issued 1398 */ 1399 protected boolean drawChild(Canvas canvas, View child, long drawingTime) { 1400 boolean more = false; 1401 1402 final int cl = child.mLeft; 1403 final int ct = child.mTop; 1404 final int cr = child.mRight; 1405 final int cb = child.mBottom; 1406 1407 final int flags = mGroupFlags; 1408 1409 if ((flags & FLAG_CLEAR_TRANSFORMATION) == FLAG_CLEAR_TRANSFORMATION) { 1410 if (mChildTransformation != null) { 1411 mChildTransformation.clear(); 1412 } 1413 mGroupFlags &= ~FLAG_CLEAR_TRANSFORMATION; 1414 } 1415 1416 Transformation transformToApply = null; 1417 final Animation a = child.getAnimation(); 1418 boolean concatMatrix = false; 1419 1420 if (a != null) { 1421 if (mInvalidateRegion == null) { 1422 mInvalidateRegion = new RectF(); 1423 } 1424 final RectF region = mInvalidateRegion; 1425 1426 final boolean initialized = a.isInitialized(); 1427 if (!initialized) { 1428 a.initialize(cr - cl, cb - ct, getWidth(), getHeight()); 1429 a.initializeInvalidateRegion(0, 0, cr - cl, cb - ct); 1430 child.onAnimationStart(); 1431 } 1432 1433 if (mChildTransformation == null) { 1434 mChildTransformation = new Transformation(); 1435 } 1436 more = a.getTransformation(drawingTime, mChildTransformation); 1437 transformToApply = mChildTransformation; 1438 1439 concatMatrix = a.willChangeTransformationMatrix(); 1440 1441 if (more) { 1442 if (!a.willChangeBounds()) { 1443 if ((flags & (FLAG_OPTIMIZE_INVALIDATE | FLAG_ANIMATION_DONE)) == 1444 FLAG_OPTIMIZE_INVALIDATE) { 1445 mGroupFlags |= FLAG_INVALIDATE_REQUIRED; 1446 } else if ((flags & FLAG_INVALIDATE_REQUIRED) == 0) { 1447 // The child need to draw an animation, potentially offscreen, so 1448 // make sure we do not cancel invalidate requests 1449 mPrivateFlags |= DRAW_ANIMATION; 1450 invalidate(cl, ct, cr, cb); 1451 } 1452 } else { 1453 a.getInvalidateRegion(0, 0, cr - cl, cb - ct, region, transformToApply); 1454 1455 // The child need to draw an animation, potentially offscreen, so 1456 // make sure we do not cancel invalidate requests 1457 mPrivateFlags |= DRAW_ANIMATION; 1458 1459 final int left = cl + (int) region.left; 1460 final int top = ct + (int) region.top; 1461 invalidate(left, top, left + (int) region.width(), top + (int) region.height()); 1462 } 1463 } 1464 } else if ((flags & FLAG_SUPPORT_STATIC_TRANSFORMATIONS) == 1465 FLAG_SUPPORT_STATIC_TRANSFORMATIONS) { 1466 if (mChildTransformation == null) { 1467 mChildTransformation = new Transformation(); 1468 } 1469 final boolean hasTransform = getChildStaticTransformation(child, mChildTransformation); 1470 if (hasTransform) { 1471 final int transformType = mChildTransformation.getTransformationType(); 1472 transformToApply = transformType != Transformation.TYPE_IDENTITY ? 1473 mChildTransformation : null; 1474 concatMatrix = (transformType & Transformation.TYPE_MATRIX) != 0; 1475 } 1476 } 1477 1478 // Sets the flag as early as possible to allow draw() implementations 1479 // to call invalidate() successfully when doing animations 1480 child.mPrivateFlags |= DRAWN; 1481 1482 if (!concatMatrix && canvas.quickReject(cl, ct, cr, cb, Canvas.EdgeType.BW) && 1483 (child.mPrivateFlags & DRAW_ANIMATION) == 0) { 1484 return more; 1485 } 1486 1487 child.computeScroll(); 1488 1489 final int sx = child.mScrollX; 1490 final int sy = child.mScrollY; 1491 1492 boolean scalingRequired = false; 1493 Bitmap cache = null; 1494 if ((flags & FLAG_CHILDREN_DRAWN_WITH_CACHE) == FLAG_CHILDREN_DRAWN_WITH_CACHE || 1495 (flags & FLAG_ALWAYS_DRAWN_WITH_CACHE) == FLAG_ALWAYS_DRAWN_WITH_CACHE) { 1496 cache = child.getDrawingCache(true); 1497 if (mAttachInfo != null) scalingRequired = mAttachInfo.mScalingRequired; 1498 } 1499 1500 final boolean hasNoCache = cache == null; 1501 1502 final int restoreTo = canvas.save(); 1503 if (hasNoCache) { 1504 canvas.translate(cl - sx, ct - sy); 1505 } else { 1506 canvas.translate(cl, ct); 1507 if (scalingRequired) { 1508 // mAttachInfo cannot be null, otherwise scalingRequired == false 1509 final float scale = 1.0f / mAttachInfo.mApplicationScale; 1510 canvas.scale(scale, scale); 1511 } 1512 } 1513 1514 float alpha = 1.0f; 1515 1516 if (transformToApply != null) { 1517 if (concatMatrix) { 1518 int transX = 0; 1519 int transY = 0; 1520 if (hasNoCache) { 1521 transX = -sx; 1522 transY = -sy; 1523 } 1524 // Undo the scroll translation, apply the transformation matrix, 1525 // then redo the scroll translate to get the correct result. 1526 canvas.translate(-transX, -transY); 1527 canvas.concat(transformToApply.getMatrix()); 1528 canvas.translate(transX, transY); 1529 mGroupFlags |= FLAG_CLEAR_TRANSFORMATION; 1530 } 1531 1532 alpha = transformToApply.getAlpha(); 1533 if (alpha < 1.0f) { 1534 mGroupFlags |= FLAG_CLEAR_TRANSFORMATION; 1535 } 1536 1537 if (alpha < 1.0f && hasNoCache) { 1538 final int multipliedAlpha = (int) (255 * alpha); 1539 if (!child.onSetAlpha(multipliedAlpha)) { 1540 canvas.saveLayerAlpha(sx, sy, sx + cr - cl, sy + cb - ct, multipliedAlpha, 1541 Canvas.HAS_ALPHA_LAYER_SAVE_FLAG | Canvas.CLIP_TO_LAYER_SAVE_FLAG); 1542 } else { 1543 child.mPrivateFlags |= ALPHA_SET; 1544 } 1545 } 1546 } else if ((child.mPrivateFlags & ALPHA_SET) == ALPHA_SET) { 1547 child.onSetAlpha(255); 1548 } 1549 1550 if ((flags & FLAG_CLIP_CHILDREN) == FLAG_CLIP_CHILDREN) { 1551 if (hasNoCache) { 1552 canvas.clipRect(sx, sy, sx + (cr - cl), sy + (cb - ct)); 1553 } else { 1554 if (!scalingRequired) { 1555 canvas.clipRect(0, 0, cr - cl, cb - ct); 1556 } else { 1557 canvas.clipRect(0, 0, cache.getWidth(), cache.getHeight()); 1558 } 1559 } 1560 } 1561 1562 if (hasNoCache) { 1563 // Fast path for layouts with no backgrounds 1564 if ((child.mPrivateFlags & SKIP_DRAW) == SKIP_DRAW) { 1565 if (ViewDebug.TRACE_HIERARCHY) { 1566 ViewDebug.trace(this, ViewDebug.HierarchyTraceType.DRAW); 1567 } 1568 child.mPrivateFlags &= ~DIRTY_MASK; 1569 child.dispatchDraw(canvas); 1570 } else { 1571 child.draw(canvas); 1572 } 1573 } else { 1574 final Paint cachePaint = mCachePaint; 1575 if (alpha < 1.0f) { 1576 cachePaint.setAlpha((int) (alpha * 255)); 1577 mGroupFlags |= FLAG_ALPHA_LOWER_THAN_ONE; 1578 } else if ((flags & FLAG_ALPHA_LOWER_THAN_ONE) == FLAG_ALPHA_LOWER_THAN_ONE) { 1579 cachePaint.setAlpha(255); 1580 mGroupFlags &= ~FLAG_ALPHA_LOWER_THAN_ONE; 1581 } 1582 if (Config.DEBUG && ViewDebug.profileDrawing) { 1583 EventLog.writeEvent(60003, hashCode()); 1584 } 1585 canvas.drawBitmap(cache, 0.0f, 0.0f, cachePaint); 1586 } 1587 1588 canvas.restoreToCount(restoreTo); 1589 1590 if (a != null && !more) { 1591 child.onSetAlpha(255); 1592 finishAnimatingView(child, a); 1593 } 1594 1595 return more; 1596 } 1597 1598 /** 1599 * By default, children are clipped to their bounds before drawing. This 1600 * allows view groups to override this behavior for animations, etc. 1601 * 1602 * @param clipChildren true to clip children to their bounds, 1603 * false otherwise 1604 * @attr ref android.R.styleable#ViewGroup_clipChildren 1605 */ 1606 public void setClipChildren(boolean clipChildren) { 1607 setBooleanFlag(FLAG_CLIP_CHILDREN, clipChildren); 1608 } 1609 1610 /** 1611 * By default, children are clipped to the padding of the ViewGroup. This 1612 * allows view groups to override this behavior 1613 * 1614 * @param clipToPadding true to clip children to the padding of the 1615 * group, false otherwise 1616 * @attr ref android.R.styleable#ViewGroup_clipToPadding 1617 */ 1618 public void setClipToPadding(boolean clipToPadding) { 1619 setBooleanFlag(FLAG_CLIP_TO_PADDING, clipToPadding); 1620 } 1621 1622 /** 1623 * {@inheritDoc} 1624 */ 1625 @Override 1626 public void dispatchSetSelected(boolean selected) { 1627 final View[] children = mChildren; 1628 final int count = mChildrenCount; 1629 for (int i = 0; i < count; i++) { 1630 children[i].setSelected(selected); 1631 } 1632 } 1633 1634 @Override 1635 protected void dispatchSetPressed(boolean pressed) { 1636 final View[] children = mChildren; 1637 final int count = mChildrenCount; 1638 for (int i = 0; i < count; i++) { 1639 children[i].setPressed(pressed); 1640 } 1641 } 1642 1643 /** 1644 * When this property is set to true, this ViewGroup supports static transformations on 1645 * children; this causes 1646 * {@link #getChildStaticTransformation(View, android.view.animation.Transformation)} to be 1647 * invoked when a child is drawn. 1648 * 1649 * Any subclass overriding 1650 * {@link #getChildStaticTransformation(View, android.view.animation.Transformation)} should 1651 * set this property to true. 1652 * 1653 * @param enabled True to enable static transformations on children, false otherwise. 1654 * 1655 * @see #FLAG_SUPPORT_STATIC_TRANSFORMATIONS 1656 */ 1657 protected void setStaticTransformationsEnabled(boolean enabled) { 1658 setBooleanFlag(FLAG_SUPPORT_STATIC_TRANSFORMATIONS, enabled); 1659 } 1660 1661 /** 1662 * {@inheritDoc} 1663 * 1664 * @see #setStaticTransformationsEnabled(boolean) 1665 */ 1666 protected boolean getChildStaticTransformation(View child, Transformation t) { 1667 return false; 1668 } 1669 1670 /** 1671 * {@hide} 1672 */ 1673 @Override 1674 protected View findViewTraversal(int id) { 1675 if (id == mID) { 1676 return this; 1677 } 1678 1679 final View[] where = mChildren; 1680 final int len = mChildrenCount; 1681 1682 for (int i = 0; i < len; i++) { 1683 View v = where[i]; 1684 1685 if ((v.mPrivateFlags & IS_ROOT_NAMESPACE) == 0) { 1686 v = v.findViewById(id); 1687 1688 if (v != null) { 1689 return v; 1690 } 1691 } 1692 } 1693 1694 return null; 1695 } 1696 1697 /** 1698 * {@hide} 1699 */ 1700 @Override 1701 protected View findViewWithTagTraversal(Object tag) { 1702 if (tag != null && tag.equals(mTag)) { 1703 return this; 1704 } 1705 1706 final View[] where = mChildren; 1707 final int len = mChildrenCount; 1708 1709 for (int i = 0; i < len; i++) { 1710 View v = where[i]; 1711 1712 if ((v.mPrivateFlags & IS_ROOT_NAMESPACE) == 0) { 1713 v = v.findViewWithTag(tag); 1714 1715 if (v != null) { 1716 return v; 1717 } 1718 } 1719 } 1720 1721 return null; 1722 } 1723 1724 /** 1725 * Adds a child view. If no layout parameters are already set on the child, the 1726 * default parameters for this ViewGroup are set on the child. 1727 * 1728 * @param child the child view to add 1729 * 1730 * @see #generateDefaultLayoutParams() 1731 */ 1732 public void addView(View child) { 1733 addView(child, -1); 1734 } 1735 1736 /** 1737 * Adds a child view. If no layout parameters are already set on the child, the 1738 * default parameters for this ViewGroup are set on the child. 1739 * 1740 * @param child the child view to add 1741 * @param index the position at which to add the child 1742 * 1743 * @see #generateDefaultLayoutParams() 1744 */ 1745 public void addView(View child, int index) { 1746 LayoutParams params = child.getLayoutParams(); 1747 if (params == null) { 1748 params = generateDefaultLayoutParams(); 1749 if (params == null) { 1750 throw new IllegalArgumentException("generateDefaultLayoutParams() cannot return null"); 1751 } 1752 } 1753 addView(child, index, params); 1754 } 1755 1756 /** 1757 * Adds a child view with this ViewGroup's default layout parameters and the 1758 * specified width and height. 1759 * 1760 * @param child the child view to add 1761 */ 1762 public void addView(View child, int width, int height) { 1763 final LayoutParams params = generateDefaultLayoutParams(); 1764 params.width = width; 1765 params.height = height; 1766 addView(child, -1, params); 1767 } 1768 1769 /** 1770 * Adds a child view with the specified layout parameters. 1771 * 1772 * @param child the child view to add 1773 * @param params the layout parameters to set on the child 1774 */ 1775 public void addView(View child, LayoutParams params) { 1776 addView(child, -1, params); 1777 } 1778 1779 /** 1780 * Adds a child view with the specified layout parameters. 1781 * 1782 * @param child the child view to add 1783 * @param index the position at which to add the child 1784 * @param params the layout parameters to set on the child 1785 */ 1786 public void addView(View child, int index, LayoutParams params) { 1787 if (DBG) { 1788 System.out.println(this + " addView"); 1789 } 1790 1791 // addViewInner() will call child.requestLayout() when setting the new LayoutParams 1792 // therefore, we call requestLayout() on ourselves before, so that the child's request 1793 // will be blocked at our level 1794 requestLayout(); 1795 invalidate(); 1796 addViewInner(child, index, params, false); 1797 } 1798 1799 /** 1800 * {@inheritDoc} 1801 */ 1802 public void updateViewLayout(View view, ViewGroup.LayoutParams params) { 1803 if (!checkLayoutParams(params)) { 1804 throw new IllegalArgumentException("Invalid LayoutParams supplied to " + this); 1805 } 1806 if (view.mParent != this) { 1807 throw new IllegalArgumentException("Given view not a child of " + this); 1808 } 1809 view.setLayoutParams(params); 1810 } 1811 1812 /** 1813 * {@inheritDoc} 1814 */ 1815 protected boolean checkLayoutParams(ViewGroup.LayoutParams p) { 1816 return p != null; 1817 } 1818 1819 /** 1820 * Interface definition for a callback to be invoked when the hierarchy 1821 * within this view changed. The hierarchy changes whenever a child is added 1822 * to or removed from this view. 1823 */ 1824 public interface OnHierarchyChangeListener { 1825 /** 1826 * Called when a new child is added to a parent view. 1827 * 1828 * @param parent the view in which a child was added 1829 * @param child the new child view added in the hierarchy 1830 */ 1831 void onChildViewAdded(View parent, View child); 1832 1833 /** 1834 * Called when a child is removed from a parent view. 1835 * 1836 * @param parent the view from which the child was removed 1837 * @param child the child removed from the hierarchy 1838 */ 1839 void onChildViewRemoved(View parent, View child); 1840 } 1841 1842 /** 1843 * Register a callback to be invoked when a child is added to or removed 1844 * from this view. 1845 * 1846 * @param listener the callback to invoke on hierarchy change 1847 */ 1848 public void setOnHierarchyChangeListener(OnHierarchyChangeListener listener) { 1849 mOnHierarchyChangeListener = listener; 1850 } 1851 1852 /** 1853 * Adds a view during layout. This is useful if in your onLayout() method, 1854 * you need to add more views (as does the list view for example). 1855 * 1856 * If index is negative, it means put it at the end of the list. 1857 * 1858 * @param child the view to add to the group 1859 * @param index the index at which the child must be added 1860 * @param params the layout parameters to associate with the child 1861 * @return true if the child was added, false otherwise 1862 */ 1863 protected boolean addViewInLayout(View child, int index, LayoutParams params) { 1864 return addViewInLayout(child, index, params, false); 1865 } 1866 1867 /** 1868 * Adds a view during layout. This is useful if in your onLayout() method, 1869 * you need to add more views (as does the list view for example). 1870 * 1871 * If index is negative, it means put it at the end of the list. 1872 * 1873 * @param child the view to add to the group 1874 * @param index the index at which the child must be added 1875 * @param params the layout parameters to associate with the child 1876 * @param preventRequestLayout if true, calling this method will not trigger a 1877 * layout request on child 1878 * @return true if the child was added, false otherwise 1879 */ 1880 protected boolean addViewInLayout(View child, int index, LayoutParams params, 1881 boolean preventRequestLayout) { 1882 child.mParent = null; 1883 addViewInner(child, index, params, preventRequestLayout); 1884 child.mPrivateFlags = (child.mPrivateFlags & ~DIRTY_MASK) | DRAWN; 1885 return true; 1886 } 1887 1888 /** 1889 * Prevents the specified child to be laid out during the next layout pass. 1890 * 1891 * @param child the child on which to perform the cleanup 1892 */ 1893 protected void cleanupLayoutState(View child) { 1894 child.mPrivateFlags &= ~View.FORCE_LAYOUT; 1895 } 1896 1897 private void addViewInner(View child, int index, LayoutParams params, 1898 boolean preventRequestLayout) { 1899 1900 if (child.getParent() != null) { 1901 throw new IllegalStateException("The specified child already has a parent. " + 1902 "You must call removeView() on the child's parent first."); 1903 } 1904 1905 if (!checkLayoutParams(params)) { 1906 params = generateLayoutParams(params); 1907 } 1908 1909 if (preventRequestLayout) { 1910 child.mLayoutParams = params; 1911 } else { 1912 child.setLayoutParams(params); 1913 } 1914 1915 if (index < 0) { 1916 index = mChildrenCount; 1917 } 1918 1919 addInArray(child, index); 1920 1921 // tell our children 1922 if (preventRequestLayout) { 1923 child.assignParent(this); 1924 } else { 1925 child.mParent = this; 1926 } 1927 1928 if (child.hasFocus()) { 1929 requestChildFocus(child, child.findFocus()); 1930 } 1931 1932 AttachInfo ai = mAttachInfo; 1933 if (ai != null) { 1934 boolean lastKeepOn = ai.mKeepScreenOn; 1935 ai.mKeepScreenOn = false; 1936 child.dispatchAttachedToWindow(mAttachInfo, (mViewFlags&VISIBILITY_MASK)); 1937 if (ai.mKeepScreenOn) { 1938 needGlobalAttributesUpdate(true); 1939 } 1940 ai.mKeepScreenOn = lastKeepOn; 1941 } 1942 1943 if (mOnHierarchyChangeListener != null) { 1944 mOnHierarchyChangeListener.onChildViewAdded(this, child); 1945 } 1946 1947 if ((child.mViewFlags & DUPLICATE_PARENT_STATE) == DUPLICATE_PARENT_STATE) { 1948 mGroupFlags |= FLAG_NOTIFY_CHILDREN_ON_DRAWABLE_STATE_CHANGE; 1949 } 1950 } 1951 1952 private void addInArray(View child, int index) { 1953 View[] children = mChildren; 1954 final int count = mChildrenCount; 1955 final int size = children.length; 1956 if (index == count) { 1957 if (size == count) { 1958 mChildren = new View[size + ARRAY_CAPACITY_INCREMENT]; 1959 System.arraycopy(children, 0, mChildren, 0, size); 1960 children = mChildren; 1961 } 1962 children[mChildrenCount++] = child; 1963 } else if (index < count) { 1964 if (size == count) { 1965 mChildren = new View[size + ARRAY_CAPACITY_INCREMENT]; 1966 System.arraycopy(children, 0, mChildren, 0, index); 1967 System.arraycopy(children, index, mChildren, index + 1, count - index); 1968 children = mChildren; 1969 } else { 1970 System.arraycopy(children, index, children, index + 1, count - index); 1971 } 1972 children[index] = child; 1973 mChildrenCount++; 1974 } else { 1975 throw new IndexOutOfBoundsException("index=" + index + " count=" + count); 1976 } 1977 } 1978 1979 // This method also sets the child's mParent to null 1980 private void removeFromArray(int index) { 1981 final View[] children = mChildren; 1982 children[index].mParent = null; 1983 final int count = mChildrenCount; 1984 if (index == count - 1) { 1985 children[--mChildrenCount] = null; 1986 } else if (index >= 0 && index < count) { 1987 System.arraycopy(children, index + 1, children, index, count - index - 1); 1988 children[--mChildrenCount] = null; 1989 } else { 1990 throw new IndexOutOfBoundsException(); 1991 } 1992 } 1993 1994 // This method also sets the children's mParent to null 1995 private void removeFromArray(int start, int count) { 1996 final View[] children = mChildren; 1997 final int childrenCount = mChildrenCount; 1998 1999 start = Math.max(0, start); 2000 final int end = Math.min(childrenCount, start + count); 2001 2002 if (start == end) { 2003 return; 2004 } 2005 2006 if (end == childrenCount) { 2007 for (int i = start; i < end; i++) { 2008 children[i].mParent = null; 2009 children[i] = null; 2010 } 2011 } else { 2012 for (int i = start; i < end; i++) { 2013 children[i].mParent = null; 2014 } 2015 2016 // Since we're looping above, we might as well do the copy, but is arraycopy() 2017 // faster than the extra 2 bounds checks we would do in the loop? 2018 System.arraycopy(children, end, children, start, childrenCount - end); 2019 2020 for (int i = childrenCount - (end - start); i < childrenCount; i++) { 2021 children[i] = null; 2022 } 2023 } 2024 2025 mChildrenCount -= (end - start); 2026 } 2027 2028 private void bindLayoutAnimation(View child) { 2029 Animation a = mLayoutAnimationController.getAnimationForView(child); 2030 child.setAnimation(a); 2031 } 2032 2033 /** 2034 * Subclasses should override this method to set layout animation 2035 * parameters on the supplied child. 2036 * 2037 * @param child the child to associate with animation parameters 2038 * @param params the child's layout parameters which hold the animation 2039 * parameters 2040 * @param index the index of the child in the view group 2041 * @param count the number of children in the view group 2042 */ 2043 protected void attachLayoutAnimationParameters(View child, 2044 LayoutParams params, int index, int count) { 2045 LayoutAnimationController.AnimationParameters animationParams = 2046 params.layoutAnimationParameters; 2047 if (animationParams == null) { 2048 animationParams = new LayoutAnimationController.AnimationParameters(); 2049 params.layoutAnimationParameters = animationParams; 2050 } 2051 2052 animationParams.count = count; 2053 animationParams.index = index; 2054 } 2055 2056 /** 2057 * {@inheritDoc} 2058 */ 2059 public void removeView(View view) { 2060 removeViewInternal(view); 2061 requestLayout(); 2062 invalidate(); 2063 } 2064 2065 /** 2066 * Removes a view during layout. This is useful if in your onLayout() method, 2067 * you need to remove more views. 2068 * 2069 * @param view the view to remove from the group 2070 */ 2071 public void removeViewInLayout(View view) { 2072 removeViewInternal(view); 2073 } 2074 2075 /** 2076 * Removes a range of views during layout. This is useful if in your onLayout() method, 2077 * you need to remove more views. 2078 * 2079 * @param start the index of the first view to remove from the group 2080 * @param count the number of views to remove from the group 2081 */ 2082 public void removeViewsInLayout(int start, int count) { 2083 removeViewsInternal(start, count); 2084 } 2085 2086 /** 2087 * Removes the view at the specified position in the group. 2088 * 2089 * @param index the position in the group of the view to remove 2090 */ 2091 public void removeViewAt(int index) { 2092 removeViewInternal(index, getChildAt(index)); 2093 requestLayout(); 2094 invalidate(); 2095 } 2096 2097 /** 2098 * Removes the specified range of views from the group. 2099 * 2100 * @param start the first position in the group of the range of views to remove 2101 * @param count the number of views to remove 2102 */ 2103 public void removeViews(int start, int count) { 2104 removeViewsInternal(start, count); 2105 requestLayout(); 2106 invalidate(); 2107 } 2108 2109 private void removeViewInternal(View view) { 2110 final int index = indexOfChild(view); 2111 if (index >= 0) { 2112 removeViewInternal(index, view); 2113 } 2114 } 2115 2116 private void removeViewInternal(int index, View view) { 2117 boolean clearChildFocus = false; 2118 if (view == mFocused) { 2119 view.clearFocusForRemoval(); 2120 clearChildFocus = true; 2121 } 2122 2123 if (view.getAnimation() != null) { 2124 addDisappearingView(view); 2125 } else if (view.mAttachInfo != null) { 2126 view.dispatchDetachedFromWindow(); 2127 } 2128 2129 if (mOnHierarchyChangeListener != null) { 2130 mOnHierarchyChangeListener.onChildViewRemoved(this, view); 2131 } 2132 2133 needGlobalAttributesUpdate(false); 2134 2135 removeFromArray(index); 2136 2137 if (clearChildFocus) { 2138 clearChildFocus(view); 2139 } 2140 } 2141 2142 private void removeViewsInternal(int start, int count) { 2143 final OnHierarchyChangeListener onHierarchyChangeListener = mOnHierarchyChangeListener; 2144 final boolean notifyListener = onHierarchyChangeListener != null; 2145 final View focused = mFocused; 2146 final boolean detach = mAttachInfo != null; 2147 View clearChildFocus = null; 2148 2149 final View[] children = mChildren; 2150 final int end = start + count; 2151 2152 for (int i = start; i < end; i++) { 2153 final View view = children[i]; 2154 2155 if (view == focused) { 2156 view.clearFocusForRemoval(); 2157 clearChildFocus = view; 2158 } 2159 2160 if (view.getAnimation() != null) { 2161 addDisappearingView(view); 2162 } else if (detach) { 2163 view.dispatchDetachedFromWindow(); 2164 } 2165 2166 needGlobalAttributesUpdate(false); 2167 2168 if (notifyListener) { 2169 onHierarchyChangeListener.onChildViewRemoved(this, view); 2170 } 2171 } 2172 2173 removeFromArray(start, count); 2174 2175 if (clearChildFocus != null) { 2176 clearChildFocus(clearChildFocus); 2177 } 2178 } 2179 2180 /** 2181 * Call this method to remove all child views from the 2182 * ViewGroup. 2183 */ 2184 public void removeAllViews() { 2185 removeAllViewsInLayout(); 2186 requestLayout(); 2187 invalidate(); 2188 } 2189 2190 /** 2191 * Called by a ViewGroup subclass to remove child views from itself, 2192 * when it must first know its size on screen before it can calculate how many 2193 * child views it will render. An example is a Gallery or a ListView, which 2194 * may "have" 50 children, but actually only render the number of children 2195 * that can currently fit inside the object on screen. Do not call 2196 * this method unless you are extending ViewGroup and understand the 2197 * view measuring and layout pipeline. 2198 */ 2199 public void removeAllViewsInLayout() { 2200 final int count = mChildrenCount; 2201 if (count <= 0) { 2202 return; 2203 } 2204 2205 final View[] children = mChildren; 2206 mChildrenCount = 0; 2207 2208 final OnHierarchyChangeListener listener = mOnHierarchyChangeListener; 2209 final boolean notify = listener != null; 2210 final View focused = mFocused; 2211 final boolean detach = mAttachInfo != null; 2212 View clearChildFocus = null; 2213 2214 needGlobalAttributesUpdate(false); 2215 2216 for (int i = count - 1; i >= 0; i--) { 2217 final View view = children[i]; 2218 2219 if (view == focused) { 2220 view.clearFocusForRemoval(); 2221 clearChildFocus = view; 2222 } 2223 2224 if (view.getAnimation() != null) { 2225 addDisappearingView(view); 2226 } else if (detach) { 2227 view.dispatchDetachedFromWindow(); 2228 } 2229 2230 if (notify) { 2231 listener.onChildViewRemoved(this, view); 2232 } 2233 2234 view.mParent = null; 2235 children[i] = null; 2236 } 2237 2238 if (clearChildFocus != null) { 2239 clearChildFocus(clearChildFocus); 2240 } 2241 } 2242 2243 /** 2244 * Finishes the removal of a detached view. This method will dispatch the detached from 2245 * window event and notify the hierarchy change listener. 2246 * 2247 * @param child the child to be definitely removed from the view hierarchy 2248 * @param animate if true and the view has an animation, the view is placed in the 2249 * disappearing views list, otherwise, it is detached from the window 2250 * 2251 * @see #attachViewToParent(View, int, android.view.ViewGroup.LayoutParams) 2252 * @see #detachAllViewsFromParent() 2253 * @see #detachViewFromParent(View) 2254 * @see #detachViewFromParent(int) 2255 */ 2256 protected void removeDetachedView(View child, boolean animate) { 2257 if (child == mFocused) { 2258 child.clearFocus(); 2259 } 2260 2261 if (animate && child.getAnimation() != null) { 2262 addDisappearingView(child); 2263 } else if (child.mAttachInfo != null) { 2264 child.dispatchDetachedFromWindow(); 2265 } 2266 2267 if (mOnHierarchyChangeListener != null) { 2268 mOnHierarchyChangeListener.onChildViewRemoved(this, child); 2269 } 2270 } 2271 2272 /** 2273 * Attaches a view to this view group. Attaching a view assigns this group as the parent, 2274 * sets the layout parameters and puts the view in the list of children so it can be retrieved 2275 * by calling {@link #getChildAt(int)}. 2276 * 2277 * This method should be called only for view which were detached from their parent. 2278 * 2279 * @param child the child to attach 2280 * @param index the index at which the child should be attached 2281 * @param params the layout parameters of the child 2282 * 2283 * @see #removeDetachedView(View, boolean) 2284 * @see #detachAllViewsFromParent() 2285 * @see #detachViewFromParent(View) 2286 * @see #detachViewFromParent(int) 2287 */ 2288 protected void attachViewToParent(View child, int index, LayoutParams params) { 2289 child.mLayoutParams = params; 2290 2291 if (index < 0) { 2292 index = mChildrenCount; 2293 } 2294 2295 addInArray(child, index); 2296 2297 child.mParent = this; 2298 child.mPrivateFlags = (child.mPrivateFlags & ~DIRTY_MASK & ~DRAWING_CACHE_VALID) | DRAWN; 2299 2300 if (child.hasFocus()) { 2301 requestChildFocus(child, child.findFocus()); 2302 } 2303 } 2304 2305 /** 2306 * Detaches a view from its parent. Detaching a view should be temporary and followed 2307 * either by a call to {@link #attachViewToParent(View, int, android.view.ViewGroup.LayoutParams)} 2308 * or a call to {@link #removeDetachedView(View, boolean)}. When a view is detached, 2309 * its parent is null and cannot be retrieved by a call to {@link #getChildAt(int)}. 2310 * 2311 * @param child the child to detach 2312 * 2313 * @see #detachViewFromParent(int) 2314 * @see #detachViewsFromParent(int, int) 2315 * @see #detachAllViewsFromParent() 2316 * @see #attachViewToParent(View, int, android.view.ViewGroup.LayoutParams) 2317 * @see #removeDetachedView(View, boolean) 2318 */ 2319 protected void detachViewFromParent(View child) { 2320 removeFromArray(indexOfChild(child)); 2321 } 2322 2323 /** 2324 * Detaches a view from its parent. Detaching a view should be temporary and followed 2325 * either by a call to {@link #attachViewToParent(View, int, android.view.ViewGroup.LayoutParams)} 2326 * or a call to {@link #removeDetachedView(View, boolean)}. When a view is detached, 2327 * its parent is null and cannot be retrieved by a call to {@link #getChildAt(int)}. 2328 * 2329 * @param index the index of the child to detach 2330 * 2331 * @see #detachViewFromParent(View) 2332 * @see #detachAllViewsFromParent() 2333 * @see #detachViewsFromParent(int, int) 2334 * @see #attachViewToParent(View, int, android.view.ViewGroup.LayoutParams) 2335 * @see #removeDetachedView(View, boolean) 2336 */ 2337 protected void detachViewFromParent(int index) { 2338 removeFromArray(index); 2339 } 2340 2341 /** 2342 * Detaches a range of view from their parent. Detaching a view should be temporary and followed 2343 * either by a call to {@link #attachViewToParent(View, int, android.view.ViewGroup.LayoutParams)} 2344 * or a call to {@link #removeDetachedView(View, boolean)}. When a view is detached, its 2345 * parent is null and cannot be retrieved by a call to {@link #getChildAt(int)}. 2346 * 2347 * @param start the first index of the childrend range to detach 2348 * @param count the number of children to detach 2349 * 2350 * @see #detachViewFromParent(View) 2351 * @see #detachViewFromParent(int) 2352 * @see #detachAllViewsFromParent() 2353 * @see #attachViewToParent(View, int, android.view.ViewGroup.LayoutParams) 2354 * @see #removeDetachedView(View, boolean) 2355 */ 2356 protected void detachViewsFromParent(int start, int count) { 2357 removeFromArray(start, count); 2358 } 2359 2360 /** 2361 * Detaches all views from the parent. Detaching a view should be temporary and followed 2362 * either by a call to {@link #attachViewToParent(View, int, android.view.ViewGroup.LayoutParams)} 2363 * or a call to {@link #removeDetachedView(View, boolean)}. When a view is detached, 2364 * its parent is null and cannot be retrieved by a call to {@link #getChildAt(int)}. 2365 * 2366 * @see #detachViewFromParent(View) 2367 * @see #detachViewFromParent(int) 2368 * @see #detachViewsFromParent(int, int) 2369 * @see #attachViewToParent(View, int, android.view.ViewGroup.LayoutParams) 2370 * @see #removeDetachedView(View, boolean) 2371 */ 2372 protected void detachAllViewsFromParent() { 2373 final int count = mChildrenCount; 2374 if (count <= 0) { 2375 return; 2376 } 2377 2378 final View[] children = mChildren; 2379 mChildrenCount = 0; 2380 2381 for (int i = count - 1; i >= 0; i--) { 2382 children[i].mParent = null; 2383 children[i] = null; 2384 } 2385 } 2386 2387 /** 2388 * Don't call or override this method. It is used for the implementation of 2389 * the view hierarchy. 2390 */ 2391 public final void invalidateChild(View child, final Rect dirty) { 2392 if (ViewDebug.TRACE_HIERARCHY) { 2393 ViewDebug.trace(this, ViewDebug.HierarchyTraceType.INVALIDATE_CHILD); 2394 } 2395 2396 ViewParent parent = this; 2397 2398 final AttachInfo attachInfo = mAttachInfo; 2399 if (attachInfo != null) { 2400 final int[] location = attachInfo.mInvalidateChildLocation; 2401 location[CHILD_LEFT_INDEX] = child.mLeft; 2402 location[CHILD_TOP_INDEX] = child.mTop; 2403 2404 // If the child is drawing an animation, we want to copy this flag onto 2405 // ourselves and the parent to make sure the invalidate request goes 2406 // through 2407 final boolean drawAnimation = (child.mPrivateFlags & DRAW_ANIMATION) == DRAW_ANIMATION; 2408 2409 // Check whether the child that requests the invalidate is fully opaque 2410 final boolean isOpaque = child.isOpaque() && !drawAnimation && 2411 child.getAnimation() != null; 2412 // Mark the child as dirty, using the appropriate flag 2413 // Make sure we do not set both flags at the same time 2414 final int opaqueFlag = isOpaque ? DIRTY_OPAQUE : DIRTY; 2415 2416 do { 2417 View view = null; 2418 if (parent instanceof View) { 2419 view = (View) parent; 2420 } 2421 2422 if (drawAnimation) { 2423 if (view != null) { 2424 view.mPrivateFlags |= DRAW_ANIMATION; 2425 } else if (parent instanceof ViewRoot) { 2426 ((ViewRoot) parent).mIsAnimating = true; 2427 } 2428 } 2429 2430 // If the parent is dirty opaque or not dirty, mark it dirty with the opaque 2431 // flag coming from the child that initiated the invalidate 2432 if (view != null && (view.mPrivateFlags & DIRTY_MASK) != DIRTY) { 2433 view.mPrivateFlags = (view.mPrivateFlags & ~DIRTY_MASK) | opaqueFlag; 2434 } 2435 2436 parent = parent.invalidateChildInParent(location, dirty); 2437 } while (parent != null); 2438 } 2439 } 2440 2441 /** 2442 * Don't call or override this method. It is used for the implementation of 2443 * the view hierarchy. 2444 * 2445 * This implementation returns null if this ViewGroup does not have a parent, 2446 * if this ViewGroup is already fully invalidated or if the dirty rectangle 2447 * does not intersect with this ViewGroup's bounds. 2448 */ 2449 public ViewParent invalidateChildInParent(final int[] location, final Rect dirty) { 2450 if (ViewDebug.TRACE_HIERARCHY) { 2451 ViewDebug.trace(this, ViewDebug.HierarchyTraceType.INVALIDATE_CHILD_IN_PARENT); 2452 } 2453 2454 if ((mPrivateFlags & DRAWN) == DRAWN) { 2455 if ((mGroupFlags & (FLAG_OPTIMIZE_INVALIDATE | FLAG_ANIMATION_DONE)) != 2456 FLAG_OPTIMIZE_INVALIDATE) { 2457 dirty.offset(location[CHILD_LEFT_INDEX] - mScrollX, 2458 location[CHILD_TOP_INDEX] - mScrollY); 2459 2460 final int left = mLeft; 2461 final int top = mTop; 2462 2463 if (dirty.intersect(0, 0, mRight - left, mBottom - top) || 2464 (mPrivateFlags & DRAW_ANIMATION) == DRAW_ANIMATION) { 2465 mPrivateFlags &= ~DRAWING_CACHE_VALID; 2466 2467 location[CHILD_LEFT_INDEX] = left; 2468 location[CHILD_TOP_INDEX] = top; 2469 2470 return mParent; 2471 } 2472 } else { 2473 mPrivateFlags &= ~DRAWN & ~DRAWING_CACHE_VALID; 2474 2475 location[CHILD_LEFT_INDEX] = mLeft; 2476 location[CHILD_TOP_INDEX] = mTop; 2477 2478 dirty.set(0, 0, mRight - location[CHILD_LEFT_INDEX], 2479 mBottom - location[CHILD_TOP_INDEX]); 2480 2481 return mParent; 2482 } 2483 } 2484 2485 return null; 2486 } 2487 2488 /** 2489 * Offset a rectangle that is in a descendant's coordinate 2490 * space into our coordinate space. 2491 * @param descendant A descendant of this view 2492 * @param rect A rectangle defined in descendant's coordinate space. 2493 */ 2494 public final void offsetDescendantRectToMyCoords(View descendant, Rect rect) { 2495 offsetRectBetweenParentAndChild(descendant, rect, true, false); 2496 } 2497 2498 /** 2499 * Offset a rectangle that is in our coordinate space into an ancestor's 2500 * coordinate space. 2501 * @param descendant A descendant of this view 2502 * @param rect A rectangle defined in descendant's coordinate space. 2503 */ 2504 public final void offsetRectIntoDescendantCoords(View descendant, Rect rect) { 2505 offsetRectBetweenParentAndChild(descendant, rect, false, false); 2506 } 2507 2508 /** 2509 * Helper method that offsets a rect either from parent to descendant or 2510 * descendant to parent. 2511 */ 2512 void offsetRectBetweenParentAndChild(View descendant, Rect rect, 2513 boolean offsetFromChildToParent, boolean clipToBounds) { 2514 2515 // already in the same coord system :) 2516 if (descendant == this) { 2517 return; 2518 } 2519 2520 ViewParent theParent = descendant.mParent; 2521 2522 // search and offset up to the parent 2523 while ((theParent != null) 2524 && (theParent instanceof View) 2525 && (theParent != this)) { 2526 2527 if (offsetFromChildToParent) { 2528 rect.offset(descendant.mLeft - descendant.mScrollX, 2529 descendant.mTop - descendant.mScrollY); 2530 if (clipToBounds) { 2531 View p = (View) theParent; 2532 rect.intersect(0, 0, p.mRight - p.mLeft, p.mBottom - p.mTop); 2533 } 2534 } else { 2535 if (clipToBounds) { 2536 View p = (View) theParent; 2537 rect.intersect(0, 0, p.mRight - p.mLeft, p.mBottom - p.mTop); 2538 } 2539 rect.offset(descendant.mScrollX - descendant.mLeft, 2540 descendant.mScrollY - descendant.mTop); 2541 } 2542 2543 descendant = (View) theParent; 2544 theParent = descendant.mParent; 2545 } 2546 2547 // now that we are up to this view, need to offset one more time 2548 // to get into our coordinate space 2549 if (theParent == this) { 2550 if (offsetFromChildToParent) { 2551 rect.offset(descendant.mLeft - descendant.mScrollX, 2552 descendant.mTop - descendant.mScrollY); 2553 } else { 2554 rect.offset(descendant.mScrollX - descendant.mLeft, 2555 descendant.mScrollY - descendant.mTop); 2556 } 2557 } else { 2558 throw new IllegalArgumentException("parameter must be a descendant of this view"); 2559 } 2560 } 2561 2562 /** 2563 * Offset the vertical location of all children of this view by the specified number of pixels. 2564 * 2565 * @param offset the number of pixels to offset 2566 * 2567 * @hide 2568 */ 2569 public void offsetChildrenTopAndBottom(int offset) { 2570 final int count = mChildrenCount; 2571 final View[] children = mChildren; 2572 2573 for (int i = 0; i < count; i++) { 2574 final View v = children[i]; 2575 v.mTop += offset; 2576 v.mBottom += offset; 2577 } 2578 } 2579 2580 /** 2581 * {@inheritDoc} 2582 */ 2583 public boolean getChildVisibleRect(View child, Rect r, android.graphics.Point offset) { 2584 int dx = child.mLeft - mScrollX; 2585 int dy = child.mTop - mScrollY; 2586 if (offset != null) { 2587 offset.x += dx; 2588 offset.y += dy; 2589 } 2590 r.offset(dx, dy); 2591 return r.intersect(0, 0, mRight - mLeft, mBottom - mTop) && 2592 (mParent == null || mParent.getChildVisibleRect(this, r, offset)); 2593 } 2594 2595 /** 2596 * {@inheritDoc} 2597 */ 2598 @Override 2599 protected abstract void onLayout(boolean changed, 2600 int l, int t, int r, int b); 2601 2602 /** 2603 * Indicates whether the view group has the ability to animate its children 2604 * after the first layout. 2605 * 2606 * @return true if the children can be animated, false otherwise 2607 */ 2608 protected boolean canAnimate() { 2609 return mLayoutAnimationController != null; 2610 } 2611 2612 /** 2613 * Runs the layout animation. Calling this method triggers a relayout of 2614 * this view group. 2615 */ 2616 public void startLayoutAnimation() { 2617 if (mLayoutAnimationController != null) { 2618 mGroupFlags |= FLAG_RUN_ANIMATION; 2619 requestLayout(); 2620 } 2621 } 2622 2623 /** 2624 * Schedules the layout animation to be played after the next layout pass 2625 * of this view group. This can be used to restart the layout animation 2626 * when the content of the view group changes or when the activity is 2627 * paused and resumed. 2628 */ 2629 public void scheduleLayoutAnimation() { 2630 mGroupFlags |= FLAG_RUN_ANIMATION; 2631 } 2632 2633 /** 2634 * Sets the layout animation controller used to animate the group's 2635 * children after the first layout. 2636 * 2637 * @param controller the animation controller 2638 */ 2639 public void setLayoutAnimation(LayoutAnimationController controller) { 2640 mLayoutAnimationController = controller; 2641 if (mLayoutAnimationController != null) { 2642 mGroupFlags |= FLAG_RUN_ANIMATION; 2643 } 2644 } 2645 2646 /** 2647 * Returns the layout animation controller used to animate the group's 2648 * children. 2649 * 2650 * @return the current animation controller 2651 */ 2652 public LayoutAnimationController getLayoutAnimation() { 2653 return mLayoutAnimationController; 2654 } 2655 2656 /** 2657 * Indicates whether the children's drawing cache is used during a layout 2658 * animation. By default, the drawing cache is enabled but this will prevent 2659 * nested layout animations from working. To nest animations, you must disable 2660 * the cache. 2661 * 2662 * @return true if the animation cache is enabled, false otherwise 2663 * 2664 * @see #setAnimationCacheEnabled(boolean) 2665 * @see View#setDrawingCacheEnabled(boolean) 2666 */ 2667 @ViewDebug.ExportedProperty 2668 public boolean isAnimationCacheEnabled() { 2669 return (mGroupFlags & FLAG_ANIMATION_CACHE) == FLAG_ANIMATION_CACHE; 2670 } 2671 2672 /** 2673 * Enables or disables the children's drawing cache during a layout animation. 2674 * By default, the drawing cache is enabled but this will prevent nested 2675 * layout animations from working. To nest animations, you must disable the 2676 * cache. 2677 * 2678 * @param enabled true to enable the animation cache, false otherwise 2679 * 2680 * @see #isAnimationCacheEnabled() 2681 * @see View#setDrawingCacheEnabled(boolean) 2682 */ 2683 public void setAnimationCacheEnabled(boolean enabled) { 2684 setBooleanFlag(FLAG_ANIMATION_CACHE, enabled); 2685 } 2686 2687 /** 2688 * Indicates whether this ViewGroup will always try to draw its children using their 2689 * drawing cache. By default this property is enabled. 2690 * 2691 * @return true if the animation cache is enabled, false otherwise 2692 * 2693 * @see #setAlwaysDrawnWithCacheEnabled(boolean) 2694 * @see #setChildrenDrawnWithCacheEnabled(boolean) 2695 * @see View#setDrawingCacheEnabled(boolean) 2696 */ 2697 @ViewDebug.ExportedProperty 2698 public boolean isAlwaysDrawnWithCacheEnabled() { 2699 return (mGroupFlags & FLAG_ALWAYS_DRAWN_WITH_CACHE) == FLAG_ALWAYS_DRAWN_WITH_CACHE; 2700 } 2701 2702 /** 2703 * Indicates whether this ViewGroup will always try to draw its children using their 2704 * drawing cache. This property can be set to true when the cache rendering is 2705 * slightly different from the children's normal rendering. Renderings can be different, 2706 * for instance, when the cache's quality is set to low. 2707 * 2708 * When this property is disabled, the ViewGroup will use the drawing cache of its 2709 * children only when asked to. It's usually the task of subclasses to tell ViewGroup 2710 * when to start using the drawing cache and when to stop using it. 2711 * 2712 * @param always true to always draw with the drawing cache, false otherwise 2713 * 2714 * @see #isAlwaysDrawnWithCacheEnabled() 2715 * @see #setChildrenDrawnWithCacheEnabled(boolean) 2716 * @see View#setDrawingCacheEnabled(boolean) 2717 * @see View#setDrawingCacheQuality(int) 2718 */ 2719 public void setAlwaysDrawnWithCacheEnabled(boolean always) { 2720 setBooleanFlag(FLAG_ALWAYS_DRAWN_WITH_CACHE, always); 2721 } 2722 2723 /** 2724 * Indicates whether the ViewGroup is currently drawing its children using 2725 * their drawing cache. 2726 * 2727 * @return true if children should be drawn with their cache, false otherwise 2728 * 2729 * @see #setAlwaysDrawnWithCacheEnabled(boolean) 2730 * @see #setChildrenDrawnWithCacheEnabled(boolean) 2731 */ 2732 @ViewDebug.ExportedProperty 2733 protected boolean isChildrenDrawnWithCacheEnabled() { 2734 return (mGroupFlags & FLAG_CHILDREN_DRAWN_WITH_CACHE) == FLAG_CHILDREN_DRAWN_WITH_CACHE; 2735 } 2736 2737 /** 2738 * Tells the ViewGroup to draw its children using their drawing cache. This property 2739 * is ignored when {@link #isAlwaysDrawnWithCacheEnabled()} is true. A child's drawing cache 2740 * will be used only if it has been enabled. 2741 * 2742 * Subclasses should call this method to start and stop using the drawing cache when 2743 * they perform performance sensitive operations, like scrolling or animating. 2744 * 2745 * @param enabled true if children should be drawn with their cache, false otherwise 2746 * 2747 * @see #setAlwaysDrawnWithCacheEnabled(boolean) 2748 * @see #isChildrenDrawnWithCacheEnabled() 2749 */ 2750 protected void setChildrenDrawnWithCacheEnabled(boolean enabled) { 2751 setBooleanFlag(FLAG_CHILDREN_DRAWN_WITH_CACHE, enabled); 2752 } 2753 2754 /** 2755 * Indicates whether the ViewGroup is drawing its children in the order defined by 2756 * {@link #getChildDrawingOrder(int, int)}. 2757 * 2758 * @return true if children drawing order is defined by {@link #getChildDrawingOrder(int, int)}, 2759 * false otherwise 2760 * 2761 * @see #setChildrenDrawingOrderEnabled(boolean) 2762 * @see #getChildDrawingOrder(int, int) 2763 */ 2764 @ViewDebug.ExportedProperty 2765 protected boolean isChildrenDrawingOrderEnabled() { 2766 return (mGroupFlags & FLAG_USE_CHILD_DRAWING_ORDER) == FLAG_USE_CHILD_DRAWING_ORDER; 2767 } 2768 2769 /** 2770 * Tells the ViewGroup whether to draw its children in the order defined by the method 2771 * {@link #getChildDrawingOrder(int, int)}. 2772 * 2773 * @param enabled true if the order of the children when drawing is determined by 2774 * {@link #getChildDrawingOrder(int, int)}, false otherwise 2775 * 2776 * @see #isChildrenDrawingOrderEnabled() 2777 * @see #getChildDrawingOrder(int, int) 2778 */ 2779 protected void setChildrenDrawingOrderEnabled(boolean enabled) { 2780 setBooleanFlag(FLAG_USE_CHILD_DRAWING_ORDER, enabled); 2781 } 2782 2783 private void setBooleanFlag(int flag, boolean value) { 2784 if (value) { 2785 mGroupFlags |= flag; 2786 } else { 2787 mGroupFlags &= ~flag; 2788 } 2789 } 2790 2791 /** 2792 * Returns an integer indicating what types of drawing caches are kept in memory. 2793 * 2794 * @see #setPersistentDrawingCache(int) 2795 * @see #setAnimationCacheEnabled(boolean) 2796 * 2797 * @return one or a combination of {@link #PERSISTENT_NO_CACHE}, 2798 * {@link #PERSISTENT_ANIMATION_CACHE}, {@link #PERSISTENT_SCROLLING_CACHE} 2799 * and {@link #PERSISTENT_ALL_CACHES} 2800 */ 2801 @ViewDebug.ExportedProperty(mapping = { 2802 @ViewDebug.IntToString(from = PERSISTENT_NO_CACHE, to = "NONE"), 2803 @ViewDebug.IntToString(from = PERSISTENT_ALL_CACHES, to = "ANIMATION"), 2804 @ViewDebug.IntToString(from = PERSISTENT_SCROLLING_CACHE, to = "SCROLLING"), 2805 @ViewDebug.IntToString(from = PERSISTENT_ALL_CACHES, to = "ALL") 2806 }) 2807 public int getPersistentDrawingCache() { 2808 return mPersistentDrawingCache; 2809 } 2810 2811 /** 2812 * Indicates what types of drawing caches should be kept in memory after 2813 * they have been created. 2814 * 2815 * @see #getPersistentDrawingCache() 2816 * @see #setAnimationCacheEnabled(boolean) 2817 * 2818 * @param drawingCacheToKeep one or a combination of {@link #PERSISTENT_NO_CACHE}, 2819 * {@link #PERSISTENT_ANIMATION_CACHE}, {@link #PERSISTENT_SCROLLING_CACHE} 2820 * and {@link #PERSISTENT_ALL_CACHES} 2821 */ 2822 public void setPersistentDrawingCache(int drawingCacheToKeep) { 2823 mPersistentDrawingCache = drawingCacheToKeep & PERSISTENT_ALL_CACHES; 2824 } 2825 2826 /** 2827 * Returns a new set of layout parameters based on the supplied attributes set. 2828 * 2829 * @param attrs the attributes to build the layout parameters from 2830 * 2831 * @return an instance of {@link android.view.ViewGroup.LayoutParams} or one 2832 * of its descendants 2833 */ 2834 public LayoutParams generateLayoutParams(AttributeSet attrs) { 2835 return new LayoutParams(getContext(), attrs); 2836 } 2837 2838 /** 2839 * Returns a safe set of layout parameters based on the supplied layout params. 2840 * When a ViewGroup is passed a View whose layout params do not pass the test of 2841 * {@link #checkLayoutParams(android.view.ViewGroup.LayoutParams)}, this method 2842 * is invoked. This method should return a new set of layout params suitable for 2843 * this ViewGroup, possibly by copying the appropriate attributes from the 2844 * specified set of layout params. 2845 * 2846 * @param p The layout parameters to convert into a suitable set of layout parameters 2847 * for this ViewGroup. 2848 * 2849 * @return an instance of {@link android.view.ViewGroup.LayoutParams} or one 2850 * of its descendants 2851 */ 2852 protected LayoutParams generateLayoutParams(ViewGroup.LayoutParams p) { 2853 return p; 2854 } 2855 2856 /** 2857 * Returns a set of default layout parameters. These parameters are requested 2858 * when the View passed to {@link #addView(View)} has no layout parameters 2859 * already set. If null is returned, an exception is thrown from addView. 2860 * 2861 * @return a set of default layout parameters or null 2862 */ 2863 protected LayoutParams generateDefaultLayoutParams() { 2864 return new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT); 2865 } 2866 2867 /** 2868 * @hide 2869 */ 2870 @Override 2871 protected boolean dispatchConsistencyCheck(int consistency) { 2872 boolean result = super.dispatchConsistencyCheck(consistency); 2873 2874 final int count = mChildrenCount; 2875 final View[] children = mChildren; 2876 for (int i = 0; i < count; i++) { 2877 if (!children[i].dispatchConsistencyCheck(consistency)) result = false; 2878 } 2879 2880 return result; 2881 } 2882 2883 /** 2884 * @hide 2885 */ 2886 @Override 2887 protected boolean onConsistencyCheck(int consistency) { 2888 boolean result = super.onConsistencyCheck(consistency); 2889 2890 final boolean checkLayout = (consistency & ViewDebug.CONSISTENCY_LAYOUT) != 0; 2891 final boolean checkDrawing = (consistency & ViewDebug.CONSISTENCY_DRAWING) != 0; 2892 2893 if (checkLayout) { 2894 final int count = mChildrenCount; 2895 final View[] children = mChildren; 2896 for (int i = 0; i < count; i++) { 2897 if (children[i].getParent() != this) { 2898 result = false; 2899 android.util.Log.d(ViewDebug.CONSISTENCY_LOG_TAG, 2900 "View " + children[i] + " has no parent/a parent that is not " + this); 2901 } 2902 } 2903 } 2904 2905 if (checkDrawing) { 2906 // If this group is dirty, check that the parent is dirty as well 2907 if ((mPrivateFlags & DIRTY_MASK) != 0) { 2908 final ViewParent parent = getParent(); 2909 if (parent != null && !(parent instanceof ViewRoot)) { 2910 if ((((View) parent).mPrivateFlags & DIRTY_MASK) == 0) { 2911 result = false; 2912 android.util.Log.d(ViewDebug.CONSISTENCY_LOG_TAG, 2913 "ViewGroup " + this + " is dirty but its parent is not: " + this); 2914 } 2915 } 2916 } 2917 } 2918 2919 return result; 2920 } 2921 2922 /** 2923 * {@inheritDoc} 2924 */ 2925 @Override 2926 protected void debug(int depth) { 2927 super.debug(depth); 2928 String output; 2929 2930 if (mFocused != null) { 2931 output = debugIndent(depth); 2932 output += "mFocused"; 2933 Log.d(VIEW_LOG_TAG, output); 2934 } 2935 if (mChildrenCount != 0) { 2936 output = debugIndent(depth); 2937 output += "{"; 2938 Log.d(VIEW_LOG_TAG, output); 2939 } 2940 int count = mChildrenCount; 2941 for (int i = 0; i < count; i++) { 2942 View child = mChildren[i]; 2943 child.debug(depth + 1); 2944 } 2945 2946 if (mChildrenCount != 0) { 2947 output = debugIndent(depth); 2948 output += "}"; 2949 Log.d(VIEW_LOG_TAG, output); 2950 } 2951 } 2952 2953 /** 2954 * Returns the position in the group of the specified child view. 2955 * 2956 * @param child the view for which to get the position 2957 * @return a positive integer representing the position of the view in the 2958 * group, or -1 if the view does not exist in the group 2959 */ 2960 public int indexOfChild(View child) { 2961 final int count = mChildrenCount; 2962 final View[] children = mChildren; 2963 for (int i = 0; i < count; i++) { 2964 if (children[i] == child) { 2965 return i; 2966 } 2967 } 2968 return -1; 2969 } 2970 2971 /** 2972 * Returns the number of children in the group. 2973 * 2974 * @return a positive integer representing the number of children in 2975 * the group 2976 */ 2977 public int getChildCount() { 2978 return mChildrenCount; 2979 } 2980 2981 /** 2982 * Returns the view at the specified position in the group. 2983 * 2984 * @param index the position at which to get the view from 2985 * @return the view at the specified position or null if the position 2986 * does not exist within the group 2987 */ 2988 public View getChildAt(int index) { 2989 try { 2990 return mChildren[index]; 2991 } catch (IndexOutOfBoundsException ex) { 2992 return null; 2993 } 2994 } 2995 2996 /** 2997 * Ask all of the children of this view to measure themselves, taking into 2998 * account both the MeasureSpec requirements for this view and its padding. 2999 * We skip children that are in the GONE state The heavy lifting is done in 3000 * getChildMeasureSpec. 3001 * 3002 * @param widthMeasureSpec The width requirements for this view 3003 * @param heightMeasureSpec The height requirements for this view 3004 */ 3005 protected void measureChildren(int widthMeasureSpec, int heightMeasureSpec) { 3006 final int size = mChildrenCount; 3007 final View[] children = mChildren; 3008 for (int i = 0; i < size; ++i) { 3009 final View child = children[i]; 3010 if ((child.mViewFlags & VISIBILITY_MASK) != GONE) { 3011 measureChild(child, widthMeasureSpec, heightMeasureSpec); 3012 } 3013 } 3014 } 3015 3016 /** 3017 * Ask one of the children of this view to measure itself, taking into 3018 * account both the MeasureSpec requirements for this view and its padding. 3019 * The heavy lifting is done in getChildMeasureSpec. 3020 * 3021 * @param child The child to measure 3022 * @param parentWidthMeasureSpec The width requirements for this view 3023 * @param parentHeightMeasureSpec The height requirements for this view 3024 */ 3025 protected void measureChild(View child, int parentWidthMeasureSpec, 3026 int parentHeightMeasureSpec) { 3027 final LayoutParams lp = child.getLayoutParams(); 3028 3029 final int childWidthMeasureSpec = getChildMeasureSpec(parentWidthMeasureSpec, 3030 mPaddingLeft + mPaddingRight, lp.width); 3031 final int childHeightMeasureSpec = getChildMeasureSpec(parentHeightMeasureSpec, 3032 mPaddingTop + mPaddingBottom, lp.height); 3033 3034 child.measure(childWidthMeasureSpec, childHeightMeasureSpec); 3035 } 3036 3037 /** 3038 * Ask one of the children of this view to measure itself, taking into 3039 * account both the MeasureSpec requirements for this view and its padding 3040 * and margins. The child must have MarginLayoutParams The heavy lifting is 3041 * done in getChildMeasureSpec. 3042 * 3043 * @param child The child to measure 3044 * @param parentWidthMeasureSpec The width requirements for this view 3045 * @param widthUsed Extra space that has been used up by the parent 3046 * horizontally (possibly by other children of the parent) 3047 * @param parentHeightMeasureSpec The height requirements for this view 3048 * @param heightUsed Extra space that has been used up by the parent 3049 * vertically (possibly by other children of the parent) 3050 */ 3051 protected void measureChildWithMargins(View child, 3052 int parentWidthMeasureSpec, int widthUsed, 3053 int parentHeightMeasureSpec, int heightUsed) { 3054 final MarginLayoutParams lp = (MarginLayoutParams) child.getLayoutParams(); 3055 3056 final int childWidthMeasureSpec = getChildMeasureSpec(parentWidthMeasureSpec, 3057 mPaddingLeft + mPaddingRight + lp.leftMargin + lp.rightMargin 3058 + widthUsed, lp.width); 3059 final int childHeightMeasureSpec = getChildMeasureSpec(parentHeightMeasureSpec, 3060 mPaddingTop + mPaddingBottom + lp.topMargin + lp.bottomMargin 3061 + heightUsed, lp.height); 3062 3063 child.measure(childWidthMeasureSpec, childHeightMeasureSpec); 3064 } 3065 3066 /** 3067 * Does the hard part of measureChildren: figuring out the MeasureSpec to 3068 * pass to a particular child. This method figures out the right MeasureSpec 3069 * for one dimension (height or width) of one child view. 3070 * 3071 * The goal is to combine information from our MeasureSpec with the 3072 * LayoutParams of the child to get the best possible results. For example, 3073 * if the this view knows its size (because its MeasureSpec has a mode of 3074 * EXACTLY), and the child has indicated in its LayoutParams that it wants 3075 * to be the same size as the parent, the parent should ask the child to 3076 * layout given an exact size. 3077 * 3078 * @param spec The requirements for this view 3079 * @param padding The padding of this view for the current dimension and 3080 * margins, if applicable 3081 * @param childDimension How big the child wants to be in the current 3082 * dimension 3083 * @return a MeasureSpec integer for the child 3084 */ 3085 public static int getChildMeasureSpec(int spec, int padding, int childDimension) { 3086 int specMode = MeasureSpec.getMode(spec); 3087 int specSize = MeasureSpec.getSize(spec); 3088 3089 int size = Math.max(0, specSize - padding); 3090 3091 int resultSize = 0; 3092 int resultMode = 0; 3093 3094 switch (specMode) { 3095 // Parent has imposed an exact size on us 3096 case MeasureSpec.EXACTLY: 3097 if (childDimension >= 0) { 3098 resultSize = childDimension; 3099 resultMode = MeasureSpec.EXACTLY; 3100 } else if (childDimension == LayoutParams.MATCH_PARENT) { 3101 // Child wants to be our size. So be it. 3102 resultSize = size; 3103 resultMode = MeasureSpec.EXACTLY; 3104 } else if (childDimension == LayoutParams.WRAP_CONTENT) { 3105 // Child wants to determine its own size. It can't be 3106 // bigger than us. 3107 resultSize = size; 3108 resultMode = MeasureSpec.AT_MOST; 3109 } 3110 break; 3111 3112 // Parent has imposed a maximum size on us 3113 case MeasureSpec.AT_MOST: 3114 if (childDimension >= 0) { 3115 // Child wants a specific size... so be it 3116 resultSize = childDimension; 3117 resultMode = MeasureSpec.EXACTLY; 3118 } else if (childDimension == LayoutParams.MATCH_PARENT) { 3119 // Child wants to be our size, but our size is not fixed. 3120 // Constrain child to not be bigger than us. 3121 resultSize = size; 3122 resultMode = MeasureSpec.AT_MOST; 3123 } else if (childDimension == LayoutParams.WRAP_CONTENT) { 3124 // Child wants to determine its own size. It can't be 3125 // bigger than us. 3126 resultSize = size; 3127 resultMode = MeasureSpec.AT_MOST; 3128 } 3129 break; 3130 3131 // Parent asked to see how big we want to be 3132 case MeasureSpec.UNSPECIFIED: 3133 if (childDimension >= 0) { 3134 // Child wants a specific size... let him have it 3135 resultSize = childDimension; 3136 resultMode = MeasureSpec.EXACTLY; 3137 } else if (childDimension == LayoutParams.MATCH_PARENT) { 3138 // Child wants to be our size... find out how big it should 3139 // be 3140 resultSize = 0; 3141 resultMode = MeasureSpec.UNSPECIFIED; 3142 } else if (childDimension == LayoutParams.WRAP_CONTENT) { 3143 // Child wants to determine its own size.... find out how 3144 // big it should be 3145 resultSize = 0; 3146 resultMode = MeasureSpec.UNSPECIFIED; 3147 } 3148 break; 3149 } 3150 return MeasureSpec.makeMeasureSpec(resultSize, resultMode); 3151 } 3152 3153 3154 /** 3155 * Removes any pending animations for views that have been removed. Call 3156 * this if you don't want animations for exiting views to stack up. 3157 */ 3158 public void clearDisappearingChildren() { 3159 if (mDisappearingChildren != null) { 3160 mDisappearingChildren.clear(); 3161 } 3162 } 3163 3164 /** 3165 * Add a view which is removed from mChildren but still needs animation 3166 * 3167 * @param v View to add 3168 */ 3169 private void addDisappearingView(View v) { 3170 ArrayList<View> disappearingChildren = mDisappearingChildren; 3171 3172 if (disappearingChildren == null) { 3173 disappearingChildren = mDisappearingChildren = new ArrayList<View>(); 3174 } 3175 3176 disappearingChildren.add(v); 3177 } 3178 3179 /** 3180 * Cleanup a view when its animation is done. This may mean removing it from 3181 * the list of disappearing views. 3182 * 3183 * @param view The view whose animation has finished 3184 * @param animation The animation, cannot be null 3185 */ 3186 private void finishAnimatingView(final View view, Animation animation) { 3187 final ArrayList<View> disappearingChildren = mDisappearingChildren; 3188 if (disappearingChildren != null) { 3189 if (disappearingChildren.contains(view)) { 3190 disappearingChildren.remove(view); 3191 3192 if (view.mAttachInfo != null) { 3193 view.dispatchDetachedFromWindow(); 3194 } 3195 3196 view.clearAnimation(); 3197 mGroupFlags |= FLAG_INVALIDATE_REQUIRED; 3198 } 3199 } 3200 3201 if (animation != null && !animation.getFillAfter()) { 3202 view.clearAnimation(); 3203 } 3204 3205 if ((view.mPrivateFlags & ANIMATION_STARTED) == ANIMATION_STARTED) { 3206 view.onAnimationEnd(); 3207 // Should be performed by onAnimationEnd() but this avoid an infinite loop, 3208 // so we'd rather be safe than sorry 3209 view.mPrivateFlags &= ~ANIMATION_STARTED; 3210 // Draw one more frame after the animation is done 3211 mGroupFlags |= FLAG_INVALIDATE_REQUIRED; 3212 } 3213 } 3214 3215 /** 3216 * {@inheritDoc} 3217 */ 3218 @Override 3219 public boolean gatherTransparentRegion(Region region) { 3220 // If no transparent regions requested, we are always opaque. 3221 final boolean meOpaque = (mPrivateFlags & View.REQUEST_TRANSPARENT_REGIONS) == 0; 3222 if (meOpaque && region == null) { 3223 // The caller doesn't care about the region, so stop now. 3224 return true; 3225 } 3226 super.gatherTransparentRegion(region); 3227 final View[] children = mChildren; 3228 final int count = mChildrenCount; 3229 boolean noneOfTheChildrenAreTransparent = true; 3230 for (int i = 0; i < count; i++) { 3231 final View child = children[i]; 3232 if ((child.mViewFlags & VISIBILITY_MASK) != GONE || child.getAnimation() != null) { 3233 if (!child.gatherTransparentRegion(region)) { 3234 noneOfTheChildrenAreTransparent = false; 3235 } 3236 } 3237 } 3238 return meOpaque || noneOfTheChildrenAreTransparent; 3239 } 3240 3241 /** 3242 * {@inheritDoc} 3243 */ 3244 public void requestTransparentRegion(View child) { 3245 if (child != null) { 3246 child.mPrivateFlags |= View.REQUEST_TRANSPARENT_REGIONS; 3247 if (mParent != null) { 3248 mParent.requestTransparentRegion(this); 3249 } 3250 } 3251 } 3252 3253 3254 @Override 3255 protected boolean fitSystemWindows(Rect insets) { 3256 boolean done = super.fitSystemWindows(insets); 3257 if (!done) { 3258 final int count = mChildrenCount; 3259 final View[] children = mChildren; 3260 for (int i = 0; i < count; i++) { 3261 done = children[i].fitSystemWindows(insets); 3262 if (done) { 3263 break; 3264 } 3265 } 3266 } 3267 return done; 3268 } 3269 3270 /** 3271 * Returns the animation listener to which layout animation events are 3272 * sent. 3273 * 3274 * @return an {@link android.view.animation.Animation.AnimationListener} 3275 */ 3276 public Animation.AnimationListener getLayoutAnimationListener() { 3277 return mAnimationListener; 3278 } 3279 3280 @Override 3281 protected void drawableStateChanged() { 3282 super.drawableStateChanged(); 3283 3284 if ((mGroupFlags & FLAG_NOTIFY_CHILDREN_ON_DRAWABLE_STATE_CHANGE) != 0) { 3285 if ((mGroupFlags & FLAG_ADD_STATES_FROM_CHILDREN) != 0) { 3286 throw new IllegalStateException("addStateFromChildren cannot be enabled if a" 3287 + " child has duplicateParentState set to true"); 3288 } 3289 3290 final View[] children = mChildren; 3291 final int count = mChildrenCount; 3292 3293 for (int i = 0; i < count; i++) { 3294 final View child = children[i]; 3295 if ((child.mViewFlags & DUPLICATE_PARENT_STATE) != 0) { 3296 child.refreshDrawableState(); 3297 } 3298 } 3299 } 3300 } 3301 3302 @Override 3303 protected int[] onCreateDrawableState(int extraSpace) { 3304 if ((mGroupFlags & FLAG_ADD_STATES_FROM_CHILDREN) == 0) { 3305 return super.onCreateDrawableState(extraSpace); 3306 } 3307 3308 int need = 0; 3309 int n = getChildCount(); 3310 for (int i = 0; i < n; i++) { 3311 int[] childState = getChildAt(i).getDrawableState(); 3312 3313 if (childState != null) { 3314 need += childState.length; 3315 } 3316 } 3317 3318 int[] state = super.onCreateDrawableState(extraSpace + need); 3319 3320 for (int i = 0; i < n; i++) { 3321 int[] childState = getChildAt(i).getDrawableState(); 3322 3323 if (childState != null) { 3324 state = mergeDrawableStates(state, childState); 3325 } 3326 } 3327 3328 return state; 3329 } 3330 3331 /** 3332 * Sets whether this ViewGroup's drawable states also include 3333 * its children's drawable states. This is used, for example, to 3334 * make a group appear to be focused when its child EditText or button 3335 * is focused. 3336 */ 3337 public void setAddStatesFromChildren(boolean addsStates) { 3338 if (addsStates) { 3339 mGroupFlags |= FLAG_ADD_STATES_FROM_CHILDREN; 3340 } else { 3341 mGroupFlags &= ~FLAG_ADD_STATES_FROM_CHILDREN; 3342 } 3343 3344 refreshDrawableState(); 3345 } 3346 3347 /** 3348 * Returns whether this ViewGroup's drawable states also include 3349 * its children's drawable states. This is used, for example, to 3350 * make a group appear to be focused when its child EditText or button 3351 * is focused. 3352 */ 3353 public boolean addStatesFromChildren() { 3354 return (mGroupFlags & FLAG_ADD_STATES_FROM_CHILDREN) != 0; 3355 } 3356 3357 /** 3358 * If {link #addStatesFromChildren} is true, refreshes this group's 3359 * drawable state (to include the states from its children). 3360 */ 3361 public void childDrawableStateChanged(View child) { 3362 if ((mGroupFlags & FLAG_ADD_STATES_FROM_CHILDREN) != 0) { 3363 refreshDrawableState(); 3364 } 3365 } 3366 3367 /** 3368 * Specifies the animation listener to which layout animation events must 3369 * be sent. Only 3370 * {@link android.view.animation.Animation.AnimationListener#onAnimationStart(Animation)} 3371 * and 3372 * {@link android.view.animation.Animation.AnimationListener#onAnimationEnd(Animation)} 3373 * are invoked. 3374 * 3375 * @param animationListener the layout animation listener 3376 */ 3377 public void setLayoutAnimationListener(Animation.AnimationListener animationListener) { 3378 mAnimationListener = animationListener; 3379 } 3380 3381 /** 3382 * LayoutParams are used by views to tell their parents how they want to be 3383 * laid out. See 3384 * {@link android.R.styleable#ViewGroup_Layout ViewGroup Layout Attributes} 3385 * for a list of all child view attributes that this class supports. 3386 * 3387 * <p> 3388 * The base LayoutParams class just describes how big the view wants to be 3389 * for both width and height. For each dimension, it can specify one of: 3390 * <ul> 3391 * <li> an exact number 3392 * <li>MATCH_PARENT, which means the view wants to be as big as its parent 3393 * (minus padding) 3394 * <li> WRAP_CONTENT, which means that the view wants to be just big enough 3395 * to enclose its content (plus padding) 3396 * </ul> 3397 * There are subclasses of LayoutParams for different subclasses of 3398 * ViewGroup. For example, AbsoluteLayout has its own subclass of 3399 * LayoutParams which adds an X and Y value. 3400 * 3401 * @attr ref android.R.styleable#ViewGroup_Layout_layout_height 3402 * @attr ref android.R.styleable#ViewGroup_Layout_layout_width 3403 */ 3404 public static class LayoutParams { 3405 /** 3406 * This value has the same meaning as {@link #MATCH_PARENT} but has 3407 * been deprecated. 3408 */ 3409 @SuppressWarnings({"UnusedDeclaration"}) 3410 @Deprecated 3411 public static final int FILL_PARENT = -1; 3412 3413 /** 3414 * Special value for the height or width requested by a View. 3415 * MATCH_PARENT means that the view wants to be as big as its parent, 3416 * minus the parent's padding, if any. 3417 */ 3418 public static final int MATCH_PARENT = -1; 3419 3420 /** 3421 * Special value for the height or width requested by a View. 3422 * WRAP_CONTENT means that the view wants to be just large enough to fit 3423 * its own internal content, taking its own padding into account. 3424 */ 3425 public static final int WRAP_CONTENT = -2; 3426 3427 /** 3428 * Information about how wide the view wants to be. Can be an exact 3429 * size, or one of the constants MATCH_PARENT or WRAP_CONTENT. 3430 */ 3431 @ViewDebug.ExportedProperty(mapping = { 3432 @ViewDebug.IntToString(from = MATCH_PARENT, to = "MATCH_PARENT"), 3433 @ViewDebug.IntToString(from = WRAP_CONTENT, to = "WRAP_CONTENT") 3434 }) 3435 public int width; 3436 3437 /** 3438 * Information about how tall the view wants to be. Can be an exact 3439 * size, or one of the constants MATCH_PARENT or WRAP_CONTENT. 3440 */ 3441 @ViewDebug.ExportedProperty(mapping = { 3442 @ViewDebug.IntToString(from = MATCH_PARENT, to = "MATCH_PARENT"), 3443 @ViewDebug.IntToString(from = WRAP_CONTENT, to = "WRAP_CONTENT") 3444 }) 3445 public int height; 3446 3447 /** 3448 * Used to animate layouts. 3449 */ 3450 public LayoutAnimationController.AnimationParameters layoutAnimationParameters; 3451 3452 /** 3453 * Creates a new set of layout parameters. The values are extracted from 3454 * the supplied attributes set and context. The XML attributes mapped 3455 * to this set of layout parameters are: 3456 * 3457 * <ul> 3458 * <li><code>layout_width</code>: the width, either an exact value, 3459 * {@link #WRAP_CONTENT} or {@link #MATCH_PARENT}</li> 3460 * <li><code>layout_height</code>: the height, either an exact value, 3461 * {@link #WRAP_CONTENT} or {@link #MATCH_PARENT}</li> 3462 * </ul> 3463 * 3464 * @param c the application environment 3465 * @param attrs the set of attributes from which to extract the layout 3466 * parameters' values 3467 */ 3468 public LayoutParams(Context c, AttributeSet attrs) { 3469 TypedArray a = c.obtainStyledAttributes(attrs, R.styleable.ViewGroup_Layout); 3470 setBaseAttributes(a, 3471 R.styleable.ViewGroup_Layout_layout_width, 3472 R.styleable.ViewGroup_Layout_layout_height); 3473 a.recycle(); 3474 } 3475 3476 /** 3477 * Creates a new set of layout parameters with the specified width 3478 * and height. 3479 * 3480 * @param width the width, either {@link #MATCH_PARENT}, 3481 * {@link #WRAP_CONTENT} or a fixed size in pixels 3482 * @param height the height, either {@link #MATCH_PARENT}, 3483 * {@link #WRAP_CONTENT} or a fixed size in pixels 3484 */ 3485 public LayoutParams(int width, int height) { 3486 this.width = width; 3487 this.height = height; 3488 } 3489 3490 /** 3491 * Copy constructor. Clones the width and height values of the source. 3492 * 3493 * @param source The layout params to copy from. 3494 */ 3495 public LayoutParams(LayoutParams source) { 3496 this.width = source.width; 3497 this.height = source.height; 3498 } 3499 3500 /** 3501 * Used internally by MarginLayoutParams. 3502 * @hide 3503 */ 3504 LayoutParams() { 3505 } 3506 3507 /** 3508 * Extracts the layout parameters from the supplied attributes. 3509 * 3510 * @param a the style attributes to extract the parameters from 3511 * @param widthAttr the identifier of the width attribute 3512 * @param heightAttr the identifier of the height attribute 3513 */ 3514 protected void setBaseAttributes(TypedArray a, int widthAttr, int heightAttr) { 3515 width = a.getLayoutDimension(widthAttr, "layout_width"); 3516 height = a.getLayoutDimension(heightAttr, "layout_height"); 3517 } 3518 3519 /** 3520 * Returns a String representation of this set of layout parameters. 3521 * 3522 * @param output the String to prepend to the internal representation 3523 * @return a String with the following format: output + 3524 * "ViewGroup.LayoutParams={ width=WIDTH, height=HEIGHT }" 3525 * 3526 * @hide 3527 */ 3528 public String debug(String output) { 3529 return output + "ViewGroup.LayoutParams={ width=" 3530 + sizeToString(width) + ", height=" + sizeToString(height) + " }"; 3531 } 3532 3533 /** 3534 * Converts the specified size to a readable String. 3535 * 3536 * @param size the size to convert 3537 * @return a String instance representing the supplied size 3538 * 3539 * @hide 3540 */ 3541 protected static String sizeToString(int size) { 3542 if (size == WRAP_CONTENT) { 3543 return "wrap-content"; 3544 } 3545 if (size == MATCH_PARENT) { 3546 return "match-parent"; 3547 } 3548 return String.valueOf(size); 3549 } 3550 } 3551 3552 /** 3553 * Per-child layout information for layouts that support margins. 3554 * See 3555 * {@link android.R.styleable#ViewGroup_MarginLayout ViewGroup Margin Layout Attributes} 3556 * for a list of all child view attributes that this class supports. 3557 */ 3558 public static class MarginLayoutParams extends ViewGroup.LayoutParams { 3559 /** 3560 * The left margin in pixels of the child. 3561 */ 3562 @ViewDebug.ExportedProperty 3563 public int leftMargin; 3564 3565 /** 3566 * The top margin in pixels of the child. 3567 */ 3568 @ViewDebug.ExportedProperty 3569 public int topMargin; 3570 3571 /** 3572 * The right margin in pixels of the child. 3573 */ 3574 @ViewDebug.ExportedProperty 3575 public int rightMargin; 3576 3577 /** 3578 * The bottom margin in pixels of the child. 3579 */ 3580 @ViewDebug.ExportedProperty 3581 public int bottomMargin; 3582 3583 /** 3584 * Creates a new set of layout parameters. The values are extracted from 3585 * the supplied attributes set and context. 3586 * 3587 * @param c the application environment 3588 * @param attrs the set of attributes from which to extract the layout 3589 * parameters' values 3590 */ 3591 public MarginLayoutParams(Context c, AttributeSet attrs) { 3592 super(); 3593 3594 TypedArray a = c.obtainStyledAttributes(attrs, R.styleable.ViewGroup_MarginLayout); 3595 setBaseAttributes(a, 3596 R.styleable.ViewGroup_MarginLayout_layout_width, 3597 R.styleable.ViewGroup_MarginLayout_layout_height); 3598 3599 int margin = a.getDimensionPixelSize( 3600 com.android.internal.R.styleable.ViewGroup_MarginLayout_layout_margin, -1); 3601 if (margin >= 0) { 3602 leftMargin = margin; 3603 topMargin = margin; 3604 rightMargin= margin; 3605 bottomMargin = margin; 3606 } else { 3607 leftMargin = a.getDimensionPixelSize( 3608 R.styleable.ViewGroup_MarginLayout_layout_marginLeft, 0); 3609 topMargin = a.getDimensionPixelSize( 3610 R.styleable.ViewGroup_MarginLayout_layout_marginTop, 0); 3611 rightMargin = a.getDimensionPixelSize( 3612 R.styleable.ViewGroup_MarginLayout_layout_marginRight, 0); 3613 bottomMargin = a.getDimensionPixelSize( 3614 R.styleable.ViewGroup_MarginLayout_layout_marginBottom, 0); 3615 } 3616 3617 a.recycle(); 3618 } 3619 3620 /** 3621 * {@inheritDoc} 3622 */ 3623 public MarginLayoutParams(int width, int height) { 3624 super(width, height); 3625 } 3626 3627 /** 3628 * Copy constructor. Clones the width, height and margin values of the source. 3629 * 3630 * @param source The layout params to copy from. 3631 */ 3632 public MarginLayoutParams(MarginLayoutParams source) { 3633 this.width = source.width; 3634 this.height = source.height; 3635 3636 this.leftMargin = source.leftMargin; 3637 this.topMargin = source.topMargin; 3638 this.rightMargin = source.rightMargin; 3639 this.bottomMargin = source.bottomMargin; 3640 } 3641 3642 /** 3643 * {@inheritDoc} 3644 */ 3645 public MarginLayoutParams(LayoutParams source) { 3646 super(source); 3647 } 3648 3649 /** 3650 * Sets the margins, in pixels. 3651 * 3652 * @param left the left margin size 3653 * @param top the top margin size 3654 * @param right the right margin size 3655 * @param bottom the bottom margin size 3656 * 3657 * @attr ref android.R.styleable#ViewGroup_MarginLayout_layout_marginLeft 3658 * @attr ref android.R.styleable#ViewGroup_MarginLayout_layout_marginTop 3659 * @attr ref android.R.styleable#ViewGroup_MarginLayout_layout_marginRight 3660 * @attr ref android.R.styleable#ViewGroup_MarginLayout_layout_marginBottom 3661 */ 3662 public void setMargins(int left, int top, int right, int bottom) { 3663 leftMargin = left; 3664 topMargin = top; 3665 rightMargin = right; 3666 bottomMargin = bottom; 3667 } 3668 } 3669} 3670