/* * Copyright (C) 2006 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package android.view; import com.android.internal.R; import android.content.Context; import android.content.res.TypedArray; import android.graphics.Bitmap; import android.graphics.Canvas; import android.graphics.Paint; import android.graphics.Rect; import android.graphics.Region; import android.graphics.RectF; import android.os.Parcelable; import android.os.SystemClock; import android.util.AttributeSet; import android.util.EventLog; import android.util.Log; import android.util.SparseArray; import android.view.animation.Animation; import android.view.animation.AnimationUtils; import android.view.animation.LayoutAnimationController; import android.view.animation.Transformation; import java.util.ArrayList; /** * <p> * A <code>ViewGroup</code> is a special view that can contain other views * (called children.) The view group is the base class for layouts and views * containers. This class also defines the * {@link android.view.ViewGroup.LayoutParams} class which serves as the base * class for layouts parameters. * </p> * * <p> * Also see {@link LayoutParams} for layout attributes. * </p> */ public abstract class ViewGroup extends View implements ViewParent, ViewManager { private static final boolean DBG = false; /** * Views which have been hidden or removed which need to be animated on * their way out. * This field should be made private, so it is hidden from the SDK. * {@hide} */ protected ArrayList<View> mDisappearingChildren; /** * Listener used to propagate events indicating when children are added * and/or removed from a view group. * This field should be made private, so it is hidden from the SDK. * {@hide} */ protected OnHierarchyChangeListener mOnHierarchyChangeListener; // The view contained within this ViewGroup that has or contains focus. private View mFocused; // The current transformation to apply on the child being drawn private Transformation mChildTransformation; private RectF mInvalidateRegion; // Target of Motion events private View mMotionTarget; private final Rect mTempRect = new Rect(); // Layout animation private LayoutAnimationController mLayoutAnimationController; private Animation.AnimationListener mAnimationListener; /** * Internal flags. * * This field should be made private, so it is hidden from the SDK. * {@hide} */ protected int mGroupFlags; // When set, ViewGroup invalidates only the child's rectangle // Set by default private static final int FLAG_CLIP_CHILDREN = 0x1; // When set, ViewGroup excludes the padding area from the invalidate rectangle // Set by default private static final int FLAG_CLIP_TO_PADDING = 0x2; // When set, dispatchDraw() will invoke invalidate(); this is set by drawChild() when // a child needs to be invalidated and FLAG_OPTIMIZE_INVALIDATE is set private static final int FLAG_INVALIDATE_REQUIRED = 0x4; // When set, dispatchDraw() will run the layout animation and unset the flag private static final int FLAG_RUN_ANIMATION = 0x8; // When set, there is either no layout animation on the ViewGroup or the layout // animation is over // Set by default private static final int FLAG_ANIMATION_DONE = 0x10; // If set, this ViewGroup has padding; if unset there is no padding and we don't need // to clip it, even if FLAG_CLIP_TO_PADDING is set private static final int FLAG_PADDING_NOT_NULL = 0x20; // When set, this ViewGroup caches its children in a Bitmap before starting a layout animation // Set by default private static final int FLAG_ANIMATION_CACHE = 0x40; // When set, this ViewGroup converts calls to invalidate(Rect) to invalidate() during a // layout animation; this avoid clobbering the hierarchy // Automatically set when the layout animation starts, depending on the animation's // characteristics private static final int FLAG_OPTIMIZE_INVALIDATE = 0x80; // When set, the next call to drawChild() will clear mChildTransformation's matrix private static final int FLAG_CLEAR_TRANSFORMATION = 0x100; // When set, this ViewGroup invokes mAnimationListener.onAnimationEnd() and removes // the children's Bitmap caches if necessary // This flag is set when the layout animation is over (after FLAG_ANIMATION_DONE is set) private static final int FLAG_NOTIFY_ANIMATION_LISTENER = 0x200; /** * When set, the drawing method will call {@link #getChildDrawingOrder(int, int)} * to get the index of the child to draw for that iteration. */ protected static final int FLAG_USE_CHILD_DRAWING_ORDER = 0x400; /** * When set, this ViewGroup supports static transformations on children; this causes * {@link #getChildStaticTransformation(View, android.view.animation.Transformation)} to be * invoked when a child is drawn. * * Any subclass overriding * {@link #getChildStaticTransformation(View, android.view.animation.Transformation)} should * set this flags in {@link #mGroupFlags}. * * {@hide} */ protected static final int FLAG_SUPPORT_STATIC_TRANSFORMATIONS = 0x800; // When the previous drawChild() invocation used an alpha value that was lower than // 1.0 and set it in mCachePaint private static final int FLAG_ALPHA_LOWER_THAN_ONE = 0x1000; /** * When set, this ViewGroup's drawable states also include those * of its children. */ private static final int FLAG_ADD_STATES_FROM_CHILDREN = 0x2000; /** * When set, this ViewGroup tries to always draw its children using their drawing cache. */ private static final int FLAG_ALWAYS_DRAWN_WITH_CACHE = 0x4000; /** * When set, and if FLAG_ALWAYS_DRAWN_WITH_CACHE is not set, this ViewGroup will try to * draw its children with their drawing cache. */ private static final int FLAG_CHILDREN_DRAWN_WITH_CACHE = 0x8000; /** * When set, this group will go through its list of children to notify them of * any drawable state change. */ private static final int FLAG_NOTIFY_CHILDREN_ON_DRAWABLE_STATE_CHANGE = 0x10000; private static final int FLAG_MASK_FOCUSABILITY = 0x60000; /** * This view will get focus before any of its descendants. */ public static final int FOCUS_BEFORE_DESCENDANTS = 0x20000; /** * This view will get focus only if none of its descendants want it. */ public static final int FOCUS_AFTER_DESCENDANTS = 0x40000; /** * This view will block any of its descendants from getting focus, even * if they are focusable. */ public static final int FOCUS_BLOCK_DESCENDANTS = 0x60000; /** * Used to map between enum in attrubutes and flag values. */ private static final int[] DESCENDANT_FOCUSABILITY_FLAGS = {FOCUS_BEFORE_DESCENDANTS, FOCUS_AFTER_DESCENDANTS, FOCUS_BLOCK_DESCENDANTS}; /** * When set, this ViewGroup should not intercept touch events. */ private static final int FLAG_DISALLOW_INTERCEPT = 0x80000; /** * Indicates which types of drawing caches are to be kept in memory. * This field should be made private, so it is hidden from the SDK. * {@hide} */ protected int mPersistentDrawingCache; /** * Used to indicate that no drawing cache should be kept in memory. */ public static final int PERSISTENT_NO_CACHE = 0x0; /** * Used to indicate that the animation drawing cache should be kept in memory. */ public static final int PERSISTENT_ANIMATION_CACHE = 0x1; /** * Used to indicate that the scrolling drawing cache should be kept in memory. */ public static final int PERSISTENT_SCROLLING_CACHE = 0x2; /** * Used to indicate that all drawing caches should be kept in memory. */ public static final int PERSISTENT_ALL_CACHES = 0x3; /** * We clip to padding when FLAG_CLIP_TO_PADDING and FLAG_PADDING_NOT_NULL * are set at the same time. */ protected static final int CLIP_TO_PADDING_MASK = FLAG_CLIP_TO_PADDING | FLAG_PADDING_NOT_NULL; // Index of the child's left position in the mLocation array private static final int CHILD_LEFT_INDEX = 0; // Index of the child's top position in the mLocation array private static final int CHILD_TOP_INDEX = 1; // Child views of this ViewGroup private View[] mChildren; // Number of valid children in the mChildren array, the rest should be null or not // considered as children private int mChildrenCount; private static final int ARRAY_INITIAL_CAPACITY = 12; private static final int ARRAY_CAPACITY_INCREMENT = 12; // Used to draw cached views private final Paint mCachePaint = new Paint(); public ViewGroup(Context context) { super(context); initViewGroup(); } public ViewGroup(Context context, AttributeSet attrs) { super(context, attrs); initViewGroup(); initFromAttributes(context, attrs); } public ViewGroup(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); initViewGroup(); initFromAttributes(context, attrs); } private void initViewGroup() { // ViewGroup doesn't draw by default setFlags(WILL_NOT_DRAW, DRAW_MASK); mGroupFlags |= FLAG_CLIP_CHILDREN; mGroupFlags |= FLAG_CLIP_TO_PADDING; mGroupFlags |= FLAG_ANIMATION_DONE; mGroupFlags |= FLAG_ANIMATION_CACHE; mGroupFlags |= FLAG_ALWAYS_DRAWN_WITH_CACHE; setDescendantFocusability(FOCUS_BEFORE_DESCENDANTS); mChildren = new View[ARRAY_INITIAL_CAPACITY]; mChildrenCount = 0; mCachePaint.setDither(false); mPersistentDrawingCache = PERSISTENT_SCROLLING_CACHE; } private void initFromAttributes(Context context, AttributeSet attrs) { TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.ViewGroup); final int N = a.getIndexCount(); for (int i = 0; i < N; i++) { int attr = a.getIndex(i); switch (attr) { case R.styleable.ViewGroup_clipChildren: setClipChildren(a.getBoolean(attr, true)); break; case R.styleable.ViewGroup_clipToPadding: setClipToPadding(a.getBoolean(attr, true)); break; case R.styleable.ViewGroup_animationCache: setAnimationCacheEnabled(a.getBoolean(attr, true)); break; case R.styleable.ViewGroup_persistentDrawingCache: setPersistentDrawingCache(a.getInt(attr, PERSISTENT_SCROLLING_CACHE)); break; case R.styleable.ViewGroup_addStatesFromChildren: setAddStatesFromChildren(a.getBoolean(attr, false)); break; case R.styleable.ViewGroup_alwaysDrawnWithCache: setAlwaysDrawnWithCacheEnabled(a.getBoolean(attr, true)); break; case R.styleable.ViewGroup_layoutAnimation: int id = a.getResourceId(attr, -1); if (id > 0) { setLayoutAnimation(AnimationUtils.loadLayoutAnimation(mContext, id)); } break; case R.styleable.ViewGroup_descendantFocusability: setDescendantFocusability(DESCENDANT_FOCUSABILITY_FLAGS[a.getInt(attr, 0)]); break; } } a.recycle(); } /** * Gets the descendant focusability of this view group. The descendant * focusability defines the relationship between this view group and its * descendants when looking for a view to take focus in * {@link #requestFocus(int, android.graphics.Rect)}. * * @return one of {@link #FOCUS_BEFORE_DESCENDANTS}, {@link #FOCUS_AFTER_DESCENDANTS}, * {@link #FOCUS_BLOCK_DESCENDANTS}. */ @ViewDebug.ExportedProperty(mapping = { @ViewDebug.IntToString(from = FOCUS_BEFORE_DESCENDANTS, to = "FOCUS_BEFORE_DESCENDANTS"), @ViewDebug.IntToString(from = FOCUS_AFTER_DESCENDANTS, to = "FOCUS_AFTER_DESCENDANTS"), @ViewDebug.IntToString(from = FOCUS_BLOCK_DESCENDANTS, to = "FOCUS_BLOCK_DESCENDANTS") }) public int getDescendantFocusability() { return mGroupFlags & FLAG_MASK_FOCUSABILITY; } /** * Set the descendant focusability of this view group. This defines the relationship * between this view group and its descendants when looking for a view to * take focus in {@link #requestFocus(int, android.graphics.Rect)}. * * @param focusability one of {@link #FOCUS_BEFORE_DESCENDANTS}, {@link #FOCUS_AFTER_DESCENDANTS}, * {@link #FOCUS_BLOCK_DESCENDANTS}. */ public void setDescendantFocusability(int focusability) { switch (focusability) { case FOCUS_BEFORE_DESCENDANTS: case FOCUS_AFTER_DESCENDANTS: case FOCUS_BLOCK_DESCENDANTS: break; default: throw new IllegalArgumentException("must be one of FOCUS_BEFORE_DESCENDANTS, " + "FOCUS_AFTER_DESCENDANTS, FOCUS_BLOCK_DESCENDANTS"); } mGroupFlags &= ~FLAG_MASK_FOCUSABILITY; mGroupFlags |= (focusability & FLAG_MASK_FOCUSABILITY); } /** * {@inheritDoc} */ @Override void handleFocusGainInternal(int direction, Rect previouslyFocusedRect) { if (mFocused != null) { mFocused.unFocus(); mFocused = null; } super.handleFocusGainInternal(direction, previouslyFocusedRect); } /** * {@inheritDoc} */ public void requestChildFocus(View child, View focused) { if (DBG) { System.out.println(this + " requestChildFocus()"); } if (getDescendantFocusability() == FOCUS_BLOCK_DESCENDANTS) { return; } // Unfocus us, if necessary super.unFocus(); // We had a previous notion of who had focus. Clear it. if (mFocused != child) { if (mFocused != null) { mFocused.unFocus(); } mFocused = child; } if (mParent != null) { mParent.requestChildFocus(this, focused); } } /** * {@inheritDoc} */ public void focusableViewAvailable(View v) { if (mParent != null // shortcut: don't report a new focusable view if we block our descendants from // getting focus && (getDescendantFocusability() != FOCUS_BLOCK_DESCENDANTS) // shortcut: don't report a new focusable view if we already are focused // (and we don't prefer our descendants) // // note: knowing that mFocused is non-null is not a good enough reason // to break the traversal since in that case we'd actually have to find // the focused view and make sure it wasn't FOCUS_AFTER_DESCENDANTS and // an ancestor of v; this will get checked for at ViewRoot && !(isFocused() && getDescendantFocusability() != FOCUS_AFTER_DESCENDANTS)) { mParent.focusableViewAvailable(v); } } /** * {@inheritDoc} */ public boolean showContextMenuForChild(View originalView) { return mParent != null && mParent.showContextMenuForChild(originalView); } /** * Find the nearest view in the specified direction that wants to take * focus. * * @param focused The view that currently has focus * @param direction One of FOCUS_UP, FOCUS_DOWN, FOCUS_LEFT, and * FOCUS_RIGHT, or 0 for not applicable. */ public View focusSearch(View focused, int direction) { if (isRootNamespace()) { // root namespace means we should consider ourselves the top of the // tree for focus searching; otherwise we could be focus searching // into other tabs. see LocalActivityManager and TabHost for more info return FocusFinder.getInstance().findNextFocus(this, focused, direction); } else if (mParent != null) { return mParent.focusSearch(focused, direction); } return null; } /** * {@inheritDoc} */ public boolean requestChildRectangleOnScreen(View child, Rect rectangle, boolean immediate) { return false; } /** * {@inheritDoc} */ @Override public boolean dispatchUnhandledMove(View focused, int direction) { return mFocused != null && mFocused.dispatchUnhandledMove(focused, direction); } /** * {@inheritDoc} */ public void clearChildFocus(View child) { if (DBG) { System.out.println(this + " clearChildFocus()"); } mFocused = null; if (mParent != null) { mParent.clearChildFocus(this); } } /** * {@inheritDoc} */ @Override public void clearFocus() { super.clearFocus(); // clear any child focus if it exists if (mFocused != null) { mFocused.clearFocus(); } } /** * {@inheritDoc} */ @Override void unFocus() { if (DBG) { System.out.println(this + " unFocus()"); } super.unFocus(); if (mFocused != null) { mFocused.unFocus(); } mFocused = null; } /** * Returns the focused child of this view, if any. The child may have focus * or contain focus. * * @return the focused child or null. */ public View getFocusedChild() { return mFocused; } /** * Returns true if this view has or contains focus * * @return true if this view has or contains focus */ @Override public boolean hasFocus() { return (mPrivateFlags & FOCUSED) != 0 || mFocused != null; } /* * (non-Javadoc) * * @see android.view.View#findFocus() */ @Override public View findFocus() { if (DBG) { System.out.println("Find focus in " + this + ": flags=" + isFocused() + ", child=" + mFocused); } if (isFocused()) { return this; } if (mFocused != null) { return mFocused.findFocus(); } return null; } /** * {@inheritDoc} */ @Override public boolean hasFocusable() { if ((mViewFlags & VISIBILITY_MASK) != VISIBLE) { return false; } if (isFocusable()) { return true; } final int descendantFocusability = getDescendantFocusability(); if (descendantFocusability != FOCUS_BLOCK_DESCENDANTS) { final int count = mChildrenCount; final View[] children = mChildren; for (int i = 0; i < count; i++) { final View child = children[i]; if (child.hasFocusable()) { return true; } } } return false; } /** * {@inheritDoc} */ @Override public void addFocusables(ArrayList<View> views, int direction) { final int focusableCount = views.size(); final int descendantFocusability = getDescendantFocusability(); if (descendantFocusability != FOCUS_BLOCK_DESCENDANTS) { final int count = mChildrenCount; final View[] children = mChildren; for (int i = 0; i < count; i++) { final View child = children[i]; if ((child.mViewFlags & VISIBILITY_MASK) == VISIBLE) { child.addFocusables(views, direction); } } } // we add ourselves (if focusable) in all cases except for when we are // FOCUS_AFTER_DESCENDANTS and there are some descendants focusable. this is // to avoid the focus search finding layouts when a more precise search // among the focusable children would be more interesting. if ( descendantFocusability != FOCUS_AFTER_DESCENDANTS || // No focusable descendants (focusableCount == views.size())) { super.addFocusables(views, direction); } } /** * {@inheritDoc} */ @Override public void dispatchWindowFocusChanged(boolean hasFocus) { super.dispatchWindowFocusChanged(hasFocus); final int count = mChildrenCount; final View[] children = mChildren; for (int i = 0; i < count; i++) { children[i].dispatchWindowFocusChanged(hasFocus); } } /** * {@inheritDoc} */ @Override public void addTouchables(ArrayList<View> views) { super.addTouchables(views); final int count = mChildrenCount; final View[] children = mChildren; for (int i = 0; i < count; i++) { final View child = children[i]; if ((child.mViewFlags & VISIBILITY_MASK) == VISIBLE) { child.addTouchables(views); } } } /** * {@inheritDoc} */ @Override public void dispatchWindowVisibilityChanged(int visibility) { super.dispatchWindowVisibilityChanged(visibility); final int count = mChildrenCount; final View[] children = mChildren; for (int i = 0; i < count; i++) { children[i].dispatchWindowVisibilityChanged(visibility); } } /** * {@inheritDoc} */ public void recomputeViewAttributes(View child) { ViewParent parent = mParent; if (parent != null) parent.recomputeViewAttributes(this); } @Override void dispatchCollectViewAttributes(int visibility) { visibility |= mViewFlags&VISIBILITY_MASK; super.dispatchCollectViewAttributes(visibility); final int count = mChildrenCount; final View[] children = mChildren; for (int i = 0; i < count; i++) { children[i].dispatchCollectViewAttributes(visibility); } } /** * {@inheritDoc} */ public void bringChildToFront(View child) { int index = indexOfChild(child); if (index >= 0) { removeFromArray(index); addInArray(child, mChildrenCount); child.mParent = this; } } /** * {@inheritDoc} */ @Override public boolean dispatchKeyEventPreIme(KeyEvent event) { if ((mPrivateFlags & (FOCUSED | HAS_BOUNDS)) == (FOCUSED | HAS_BOUNDS)) { return super.dispatchKeyEventPreIme(event); } else if (mFocused != null && (mFocused.mPrivateFlags & HAS_BOUNDS) == HAS_BOUNDS) { return mFocused.dispatchKeyEventPreIme(event); } return false; } /** * {@inheritDoc} */ @Override public boolean dispatchKeyEvent(KeyEvent event) { if ((mPrivateFlags & (FOCUSED | HAS_BOUNDS)) == (FOCUSED | HAS_BOUNDS)) { return super.dispatchKeyEvent(event); } else if (mFocused != null && (mFocused.mPrivateFlags & HAS_BOUNDS) == HAS_BOUNDS) { return mFocused.dispatchKeyEvent(event); } return false; } /** * {@inheritDoc} */ @Override public boolean dispatchKeyShortcutEvent(KeyEvent event) { if ((mPrivateFlags & (FOCUSED | HAS_BOUNDS)) == (FOCUSED | HAS_BOUNDS)) { return super.dispatchKeyShortcutEvent(event); } else if (mFocused != null && (mFocused.mPrivateFlags & HAS_BOUNDS) == HAS_BOUNDS) { return mFocused.dispatchKeyShortcutEvent(event); } return false; } /** * {@inheritDoc} */ @Override public boolean dispatchTrackballEvent(MotionEvent event) { if ((mPrivateFlags & (FOCUSED | HAS_BOUNDS)) == (FOCUSED | HAS_BOUNDS)) { return super.dispatchTrackballEvent(event); } else if (mFocused != null && (mFocused.mPrivateFlags & HAS_BOUNDS) == HAS_BOUNDS) { return mFocused.dispatchTrackballEvent(event); } return false; } /** * {@inheritDoc} */ @Override public boolean dispatchTouchEvent(MotionEvent ev) { final int action = ev.getAction(); final float xf = ev.getX(); final float yf = ev.getY(); final float scrolledXFloat = xf + mScrollX; final float scrolledYFloat = yf + mScrollY; final Rect frame = mTempRect; boolean disallowIntercept = (mGroupFlags & FLAG_DISALLOW_INTERCEPT) != 0; if (action == MotionEvent.ACTION_DOWN) { if (mMotionTarget != null) { // this is weird, we got a pen down, but we thought it was // already down! // XXX: We should probably send an ACTION_UP to the current // target. mMotionTarget = null; } // If we're disallowing intercept or if we're allowing and we didn't // intercept if (disallowIntercept || !onInterceptTouchEvent(ev)) { // reset this event's action (just to protect ourselves) ev.setAction(MotionEvent.ACTION_DOWN); // We know we want to dispatch the event down, find a child // who can handle it, start with the front-most child. final int scrolledXInt = (int) scrolledXFloat; final int scrolledYInt = (int) scrolledYFloat; final View[] children = mChildren; final int count = mChildrenCount; for (int i = count - 1; i >= 0; i--) { final View child = children[i]; if ((child.mViewFlags & VISIBILITY_MASK) == VISIBLE || child.getAnimation() != null) { child.getHitRect(frame); if (frame.contains(scrolledXInt, scrolledYInt)) { // offset the event to the view's coordinate system final float xc = scrolledXFloat - child.mLeft; final float yc = scrolledYFloat - child.mTop; ev.setLocation(xc, yc); if (child.dispatchTouchEvent(ev)) { // Event handled, we have a target now. mMotionTarget = child; return true; } // The event didn't get handled, try the next view. // Don't reset the event's location, it's not // necessary here. } } } } } boolean isUpOrCancel = (action == MotionEvent.ACTION_UP) || (action == MotionEvent.ACTION_CANCEL); if (isUpOrCancel) { // Note, we've already copied the previous state to our local // variable, so this takes effect on the next event mGroupFlags &= ~FLAG_DISALLOW_INTERCEPT; } // The event wasn't an ACTION_DOWN, dispatch it to our target if // we have one. final View target = mMotionTarget; if (target == null) { // We don't have a target, this means we're handling the // event as a regular view. ev.setLocation(xf, yf); return super.dispatchTouchEvent(ev); } // if have a target, see if we're allowed to and want to intercept its // events if (!disallowIntercept && onInterceptTouchEvent(ev)) { final float xc = scrolledXFloat - (float) target.mLeft; final float yc = scrolledYFloat - (float) target.mTop; ev.setAction(MotionEvent.ACTION_CANCEL); ev.setLocation(xc, yc); if (!target.dispatchTouchEvent(ev)) { // target didn't handle ACTION_CANCEL. not much we can do // but they should have. } // clear the target mMotionTarget = null; // Don't dispatch this event to our own view, because we already // saw it when intercepting; we just want to give the following // event to the normal onTouchEvent(). return true; } if (isUpOrCancel) { mMotionTarget = null; } // finally offset the event to the target's coordinate system and // dispatch the event. final float xc = scrolledXFloat - (float) target.mLeft; final float yc = scrolledYFloat - (float) target.mTop; ev.setLocation(xc, yc); return target.dispatchTouchEvent(ev); } /** * {@inheritDoc} */ public void requestDisallowInterceptTouchEvent(boolean disallowIntercept) { if (disallowIntercept == ((mGroupFlags & FLAG_DISALLOW_INTERCEPT) != 0)) { // We're already in this state, assume our ancestors are too return; } if (disallowIntercept) { mGroupFlags |= FLAG_DISALLOW_INTERCEPT; } else { mGroupFlags &= ~FLAG_DISALLOW_INTERCEPT; } // Pass it up to our parent if (mParent != null) { mParent.requestDisallowInterceptTouchEvent(disallowIntercept); } } /** * Implement this method to intercept all touch screen motion events. This * allows you to watch events as they are dispatched to your children, and * take ownership of the current gesture at any point. * * <p>Using this function takes some care, as it has a fairly complicated * interaction with {@link View#onTouchEvent(MotionEvent) * View.onTouchEvent(MotionEvent)}, and using it requires implementing * that method as well as this one in the correct way. Events will be * received in the following order: * * <ol> * <li> You will receive the down event here. * <li> The down event will be handled either by a child of this view * group, or given to your own onTouchEvent() method to handle; this means * you should implement onTouchEvent() to return true, so you will * continue to see the rest of the gesture (instead of looking for * a parent view to handle it). Also, by returning true from * onTouchEvent(), you will not receive any following * events in onInterceptTouchEvent() and all touch processing must * happen in onTouchEvent() like normal. * <li> For as long as you return false from this function, each following * event (up to and including the final up) will be delivered first here * and then to the target's onTouchEvent(). * <li> If you return true from here, you will not receive any * following events: the target view will receive the same event but * with the action {@link MotionEvent#ACTION_CANCEL}, and all further * events will be delivered to your onTouchEvent() method and no longer * appear here. * </ol> * * @param ev The motion event being dispatched down the hierarchy. * @return Return true to steal motion events from the children and have * them dispatched to this ViewGroup through onTouchEvent(). * The current target will receive an ACTION_CANCEL event, and no further * messages will be delivered here. */ public boolean onInterceptTouchEvent(MotionEvent ev) { return false; } /** * {@inheritDoc} * * Looks for a view to give focus to respecting the setting specified by * {@link #getDescendantFocusability()}. * * Uses {@link #onRequestFocusInDescendants(int, android.graphics.Rect)} to * find focus within the children of this group when appropriate. * * @see #FOCUS_BEFORE_DESCENDANTS * @see #FOCUS_AFTER_DESCENDANTS * @see #FOCUS_BLOCK_DESCENDANTS * @see #onRequestFocusInDescendants */ @Override public boolean requestFocus(int direction, Rect previouslyFocusedRect) { if (DBG) { System.out.println(this + " ViewGroup.requestFocus direction=" + direction); } int descendantFocusability = getDescendantFocusability(); switch (descendantFocusability) { case FOCUS_BLOCK_DESCENDANTS: return super.requestFocus(direction, previouslyFocusedRect); case FOCUS_BEFORE_DESCENDANTS: { final boolean took = super.requestFocus(direction, previouslyFocusedRect); return took ? took : onRequestFocusInDescendants(direction, previouslyFocusedRect); } case FOCUS_AFTER_DESCENDANTS: { final boolean took = onRequestFocusInDescendants(direction, previouslyFocusedRect); return took ? took : super.requestFocus(direction, previouslyFocusedRect); } default: throw new IllegalStateException("descendant focusability must be " + "one of FOCUS_BEFORE_DESCENDANTS, FOCUS_AFTER_DESCENDANTS, FOCUS_BLOCK_DESCENDANTS " + "but is " + descendantFocusability); } } /** * Look for a descendant to call {@link View#requestFocus} on. * Called by {@link ViewGroup#requestFocus(int, android.graphics.Rect)} * when it wants to request focus within its children. Override this to * customize how your {@link ViewGroup} requests focus within its children. * @param direction One of FOCUS_UP, FOCUS_DOWN, FOCUS_LEFT, and FOCUS_RIGHT * @param previouslyFocusedRect The rectangle (in this View's coordinate system) * to give a finer grained hint about where focus is coming from. May be null * if there is no hint. * @return Whether focus was taken. */ @SuppressWarnings({"ConstantConditions"}) protected boolean onRequestFocusInDescendants(int direction, Rect previouslyFocusedRect) { int index; int increment; int end; int count = mChildrenCount; if ((direction & FOCUS_FORWARD) != 0) { index = 0; increment = 1; end = count; } else { index = count - 1; increment = -1; end = -1; } final View[] children = mChildren; for (int i = index; i != end; i += increment) { View child = children[i]; if ((child.mViewFlags & VISIBILITY_MASK) == VISIBLE) { if (child.requestFocus(direction, previouslyFocusedRect)) { return true; } } } return false; } /** * {@inheritDoc} */ @Override void dispatchAttachedToWindow(AttachInfo info, int visibility) { super.dispatchAttachedToWindow(info, visibility); visibility |= mViewFlags & VISIBILITY_MASK; final int count = mChildrenCount; final View[] children = mChildren; for (int i = 0; i < count; i++) { children[i].dispatchAttachedToWindow(info, visibility); } } /** * {@inheritDoc} */ @Override void dispatchDetachedFromWindow() { // If we still have a motion target, we are still in the process of // dispatching motion events to a child; we need to get rid of that // child to avoid dispatching events to it after the window is torn // down. To make sure we keep the child in a consistent state, we // first send it an ACTION_CANCEL motion event. if (mMotionTarget != null) { final long now = SystemClock.uptimeMillis(); final MotionEvent event = MotionEvent.obtain(now, now, MotionEvent.ACTION_CANCEL, 0.0f, 0.0f, 0); mMotionTarget.dispatchTouchEvent(event); event.recycle(); mMotionTarget = null; } final int count = mChildrenCount; final View[] children = mChildren; for (int i = 0; i < count; i++) { children[i].dispatchDetachedFromWindow(); } super.dispatchDetachedFromWindow(); } /** * {@inheritDoc} */ @Override public void setPadding(int left, int top, int right, int bottom) { super.setPadding(left, top, right, bottom); if ((mPaddingLeft | mPaddingTop | mPaddingRight | mPaddingRight) != 0) { mGroupFlags |= FLAG_PADDING_NOT_NULL; } else { mGroupFlags &= ~FLAG_PADDING_NOT_NULL; } } /** * {@inheritDoc} */ @Override protected void dispatchSaveInstanceState(SparseArray<Parcelable> container) { super.dispatchSaveInstanceState(container); final int count = mChildrenCount; final View[] children = mChildren; for (int i = 0; i < count; i++) { children[i].dispatchSaveInstanceState(container); } } /** * Perform dispatching of a {@link #saveHierarchyState freeze()} to only this view, * not to its children. For use when overriding * {@link #dispatchSaveInstanceState dispatchFreeze()} to allow subclasses to freeze * their own state but not the state of their children. * * @param container the container */ protected void dispatchFreezeSelfOnly(SparseArray<Parcelable> container) { super.dispatchSaveInstanceState(container); } /** * {@inheritDoc} */ @Override protected void dispatchRestoreInstanceState(SparseArray<Parcelable> container) { super.dispatchRestoreInstanceState(container); final int count = mChildrenCount; final View[] children = mChildren; for (int i = 0; i < count; i++) { children[i].dispatchRestoreInstanceState(container); } } /** * Perform dispatching of a {@link #restoreHierarchyState thaw()} to only this view, * not to its children. For use when overriding * {@link #dispatchRestoreInstanceState dispatchThaw()} to allow subclasses to thaw * their own state but not the state of their children. * * @param container the container */ protected void dispatchThawSelfOnly(SparseArray<Parcelable> container) { super.dispatchRestoreInstanceState(container); } /** * Enables or disables the drawing cache for each child of this view group. * * @param enabled true to enable the cache, false to dispose of it */ protected void setChildrenDrawingCacheEnabled(boolean enabled) { if (enabled || (mPersistentDrawingCache & PERSISTENT_ALL_CACHES) != PERSISTENT_ALL_CACHES) { final View[] children = mChildren; final int count = mChildrenCount; for (int i = 0; i < count; i++) { children[i].setDrawingCacheEnabled(enabled); } } } @Override protected void onAnimationStart() { super.onAnimationStart(); // When this ViewGroup's animation starts, build the cache for the children if ((mGroupFlags & FLAG_ANIMATION_CACHE) == FLAG_ANIMATION_CACHE) { final int count = mChildrenCount; final View[] children = mChildren; for (int i = 0; i < count; i++) { final View child = children[i]; if ((child.mViewFlags & VISIBILITY_MASK) == VISIBLE) { child.setDrawingCacheEnabled(true); child.buildDrawingCache(); } } mGroupFlags |= FLAG_CHILDREN_DRAWN_WITH_CACHE; } } @Override protected void onAnimationEnd() { super.onAnimationEnd(); // When this ViewGroup's animation ends, destroy the cache of the children if ((mGroupFlags & FLAG_ANIMATION_CACHE) == FLAG_ANIMATION_CACHE) { mGroupFlags &= ~FLAG_CHILDREN_DRAWN_WITH_CACHE; if ((mPersistentDrawingCache & PERSISTENT_ANIMATION_CACHE) == 0) { setChildrenDrawingCacheEnabled(false); } } } /** * {@inheritDoc} */ @Override protected void dispatchDraw(Canvas canvas) { final int count = mChildrenCount; final View[] children = mChildren; int flags = mGroupFlags; if ((flags & FLAG_RUN_ANIMATION) != 0 && canAnimate()) { final boolean cache = (mGroupFlags & FLAG_ANIMATION_CACHE) == FLAG_ANIMATION_CACHE; for (int i = 0; i < count; i++) { final View child = children[i]; if ((child.mViewFlags & VISIBILITY_MASK) == VISIBLE) { final LayoutParams params = child.getLayoutParams(); attachLayoutAnimationParameters(child, params, i, count); bindLayoutAnimation(child); if (cache) { child.setDrawingCacheEnabled(true); child.buildDrawingCache(); } } } final LayoutAnimationController controller = mLayoutAnimationController; if (controller.willOverlap()) { mGroupFlags |= FLAG_OPTIMIZE_INVALIDATE; } controller.start(); mGroupFlags &= ~FLAG_RUN_ANIMATION; mGroupFlags &= ~FLAG_ANIMATION_DONE; if (cache) { mGroupFlags |= FLAG_CHILDREN_DRAWN_WITH_CACHE; } if (mAnimationListener != null) { mAnimationListener.onAnimationStart(controller.getAnimation()); } } int saveCount = 0; final boolean clipToPadding = (flags & CLIP_TO_PADDING_MASK) == CLIP_TO_PADDING_MASK; if (clipToPadding) { saveCount = canvas.save(); canvas.clipRect(mScrollX + mPaddingLeft, mScrollY + mPaddingTop, mScrollX + mRight - mLeft - mPaddingRight, mScrollY + mBottom - mTop - mPaddingBottom); } // We will draw our child's animation, let's reset the flag mPrivateFlags &= ~DRAW_ANIMATION; mGroupFlags &= ~FLAG_INVALIDATE_REQUIRED; boolean more = false; final long drawingTime = getDrawingTime(); if ((flags & FLAG_USE_CHILD_DRAWING_ORDER) == 0) { for (int i = 0; i < count; i++) { final View child = children[i]; if ((child.mViewFlags & VISIBILITY_MASK) == VISIBLE || child.getAnimation() != null) { more |= drawChild(canvas, child, drawingTime); } } } else { for (int i = 0; i < count; i++) { final View child = children[getChildDrawingOrder(count, i)]; if ((child.mViewFlags & VISIBILITY_MASK) == VISIBLE || child.getAnimation() != null) { more |= drawChild(canvas, child, drawingTime); } } } // Draw any disappearing views that have animations if (mDisappearingChildren != null) { final ArrayList<View> disappearingChildren = mDisappearingChildren; final int disappearingCount = disappearingChildren.size() - 1; // Go backwards -- we may delete as animations finish for (int i = disappearingCount; i >= 0; i--) { final View child = disappearingChildren.get(i); more |= drawChild(canvas, child, drawingTime); } } if (clipToPadding) { canvas.restoreToCount(saveCount); } // mGroupFlags might have been updated by drawChild() flags = mGroupFlags; if ((flags & FLAG_INVALIDATE_REQUIRED) == FLAG_INVALIDATE_REQUIRED) { invalidate(); } if ((flags & FLAG_ANIMATION_DONE) == 0 && (flags & FLAG_NOTIFY_ANIMATION_LISTENER) == 0 && mLayoutAnimationController.isDone() && !more) { // We want to erase the drawing cache and notify the listener after the // next frame is drawn because one extra invalidate() is caused by // drawChild() after the animation is over mGroupFlags |= FLAG_NOTIFY_ANIMATION_LISTENER; final Runnable end = new Runnable() { public void run() { notifyAnimationListener(); } }; post(end); } } /** * Returns the index of the child to draw for this iteration. Override this * if you want to change the drawing order of children. By default, it * returns i. * <p> * NOTE: In order for this method to be called, the * {@link #FLAG_USE_CHILD_DRAWING_ORDER} must be set. * * @param i The current iteration. * @return The index of the child to draw this iteration. */ protected int getChildDrawingOrder(int childCount, int i) { return i; } private void notifyAnimationListener() { mGroupFlags &= ~FLAG_NOTIFY_ANIMATION_LISTENER; mGroupFlags |= FLAG_ANIMATION_DONE; if (mAnimationListener != null) { final Runnable end = new Runnable() { public void run() { mAnimationListener.onAnimationEnd(mLayoutAnimationController.getAnimation()); } }; post(end); } if ((mGroupFlags & FLAG_ANIMATION_CACHE) == FLAG_ANIMATION_CACHE) { mGroupFlags &= ~FLAG_CHILDREN_DRAWN_WITH_CACHE; if ((mPersistentDrawingCache & PERSISTENT_ANIMATION_CACHE) == 0) { setChildrenDrawingCacheEnabled(false); } } invalidate(); } /** * Draw one child of this View Group. This method is responsible for getting * the canvas in the right state. This includes clipping, translating so * that the child's scrolled origin is at 0, 0, and applying any animation * transformations. * * @param canvas The canvas on which to draw the child * @param child Who to draw * @param drawingTime The time at which draw is occuring * @return True if an invalidate() was issued */ protected boolean drawChild(Canvas canvas, View child, long drawingTime) { boolean more = false; final int cl = child.mLeft; final int ct = child.mTop; final int cr = child.mRight; final int cb = child.mBottom; final int flags = mGroupFlags; if ((flags & FLAG_CLEAR_TRANSFORMATION) == FLAG_CLEAR_TRANSFORMATION) { if (mChildTransformation != null) { mChildTransformation.clear(); } mGroupFlags &= ~FLAG_CLEAR_TRANSFORMATION; } Transformation transformToApply = null; final Animation a = child.getAnimation(); boolean concatMatrix = false; if (a != null) { if (mInvalidateRegion == null) { mInvalidateRegion = new RectF(); } final RectF region = mInvalidateRegion; final boolean initialized = a.isInitialized(); if (!initialized) { a.initialize(cr - cl, cb - ct, getWidth(), getHeight()); a.initializeInvalidateRegion(0, 0, cr - cl, cb - ct); child.onAnimationStart(); } if (mChildTransformation == null) { mChildTransformation = new Transformation(); } more = a.getTransformation(drawingTime, mChildTransformation); transformToApply = mChildTransformation; concatMatrix = a.willChangeTransformationMatrix(); if (more) { if (!a.willChangeBounds()) { if ((flags & (FLAG_OPTIMIZE_INVALIDATE | FLAG_ANIMATION_DONE)) == FLAG_OPTIMIZE_INVALIDATE) { mGroupFlags |= FLAG_INVALIDATE_REQUIRED; } else if ((flags & FLAG_INVALIDATE_REQUIRED) == 0) { // The child need to draw an animation, potentially offscreen, so // make sure we do not cancel invalidate requests mPrivateFlags |= DRAW_ANIMATION; invalidate(cl, ct, cr, cb); } } else { a.getInvalidateRegion(0, 0, cr - cl, cb - ct, region, transformToApply); // The child need to draw an animation, potentially offscreen, so // make sure we do not cancel invalidate requests mPrivateFlags |= DRAW_ANIMATION; final int left = cl + (int) region.left; final int top = ct + (int) region.top; invalidate(left, top, left + (int) region.width(), top + (int) region.height()); } } } else if ((flags & FLAG_SUPPORT_STATIC_TRANSFORMATIONS) == FLAG_SUPPORT_STATIC_TRANSFORMATIONS) { if (mChildTransformation == null) { mChildTransformation = new Transformation(); } final boolean hasTransform = getChildStaticTransformation(child, mChildTransformation); if (hasTransform) { final int transformType = mChildTransformation.getTransformationType(); transformToApply = transformType != Transformation.TYPE_IDENTITY ? mChildTransformation : null; concatMatrix = (transformType & Transformation.TYPE_MATRIX) != 0; } } // Clear the flag as early as possible to allow draw() implementations // to call invalidate() successfully when doing animations child.mPrivateFlags |= DRAWN; if (!concatMatrix && canvas.quickReject(cl, ct, cr, cb, Canvas.EdgeType.BW) && (child.mPrivateFlags & DRAW_ANIMATION) == 0) { return more; } child.computeScroll(); final int sx = child.mScrollX; final int sy = child.mScrollY; Bitmap cache = null; if ((flags & FLAG_CHILDREN_DRAWN_WITH_CACHE) == FLAG_CHILDREN_DRAWN_WITH_CACHE || (flags & FLAG_ALWAYS_DRAWN_WITH_CACHE) == FLAG_ALWAYS_DRAWN_WITH_CACHE) { cache = child.getDrawingCache(); } final boolean hasNoCache = cache == null; final int restoreTo = canvas.save(); if (hasNoCache) { canvas.translate(cl - sx, ct - sy); } else { canvas.translate(cl, ct); } float alpha = 1.0f; if (transformToApply != null) { if (concatMatrix) { int transX = 0; int transY = 0; if (hasNoCache) { transX = -sx; transY = -sy; } // Undo the scroll translation, apply the transformation matrix, // then redo the scroll translate to get the correct result. canvas.translate(-transX, -transY); canvas.concat(transformToApply.getMatrix()); canvas.translate(transX, transY); mGroupFlags |= FLAG_CLEAR_TRANSFORMATION; } alpha = transformToApply.getAlpha(); if (alpha < 1.0f) { mGroupFlags |= FLAG_CLEAR_TRANSFORMATION; } if (alpha < 1.0f && hasNoCache) { final int multipliedAlpha = (int) (255 * alpha); if (!child.onSetAlpha(multipliedAlpha)) { canvas.saveLayerAlpha(sx, sy, sx + cr - cl, sy + cb - ct, multipliedAlpha, Canvas.HAS_ALPHA_LAYER_SAVE_FLAG | Canvas.CLIP_TO_LAYER_SAVE_FLAG); } else { child.mPrivateFlags |= ALPHA_SET; } } } else if ((child.mPrivateFlags & ALPHA_SET) == ALPHA_SET) { child.onSetAlpha(255); } if ((flags & FLAG_CLIP_CHILDREN) == FLAG_CLIP_CHILDREN) { if (hasNoCache) { canvas.clipRect(sx, sy, sx + (cr - cl), sy + (cb - ct)); } else { canvas.clipRect(0, 0, cr - cl, cb - ct); } } if (hasNoCache) { // Fast path for layouts with no backgrounds if ((child.mPrivateFlags & SKIP_DRAW) == SKIP_DRAW) { if (ViewDebug.TRACE_HIERARCHY) { ViewDebug.trace(this, ViewDebug.HierarchyTraceType.DRAW); } child.dispatchDraw(canvas); } else { child.draw(canvas); } } else { final Paint cachePaint = mCachePaint; if (alpha < 1.0f) { cachePaint.setAlpha((int) (alpha * 255)); mGroupFlags |= FLAG_ALPHA_LOWER_THAN_ONE; } else if ((flags & FLAG_ALPHA_LOWER_THAN_ONE) == FLAG_ALPHA_LOWER_THAN_ONE) { cachePaint.setAlpha(255); mGroupFlags &= ~FLAG_ALPHA_LOWER_THAN_ONE; } if (ViewRoot.PROFILE_DRAWING) { EventLog.writeEvent(60003, hashCode()); } canvas.drawBitmap(cache, 0.0f, 0.0f, cachePaint); } canvas.restoreToCount(restoreTo); if (a != null && !more) { child.onSetAlpha(255); finishAnimatingView(child, a); } return more; } /** * By default, children are clipped to their bounds before drawing. This * allows view groups to override this behavior for animations, etc. * * @param clipChildren true to clip children to their bounds, * false otherwise * @attr ref android.R.styleable#ViewGroup_clipChildren */ public void setClipChildren(boolean clipChildren) { setBooleanFlag(FLAG_CLIP_CHILDREN, clipChildren); } /** * By default, children are clipped to the padding of the ViewGroup. This * allows view groups to override this behavior * * @param clipToPadding true to clip children to the padding of the * group, false otherwise * @attr ref android.R.styleable#ViewGroup_clipToPadding */ public void setClipToPadding(boolean clipToPadding) { setBooleanFlag(FLAG_CLIP_TO_PADDING, clipToPadding); } /** * {@inheritDoc} */ @Override public void dispatchSetSelected(boolean selected) { final View[] children = mChildren; final int count = mChildrenCount; for (int i = 0; i < count; i++) { children[i].setSelected(selected); } } @Override protected void dispatchSetPressed(boolean pressed) { final View[] children = mChildren; final int count = mChildrenCount; for (int i = 0; i < count; i++) { children[i].setPressed(pressed); } } /** * When this property is set to true, this ViewGroup supports static transformations on * children; this causes * {@link #getChildStaticTransformation(View, android.view.animation.Transformation)} to be * invoked when a child is drawn. * * Any subclass overriding * {@link #getChildStaticTransformation(View, android.view.animation.Transformation)} should * set this property to true. * * @param enabled True to enable static transformations on children, false otherwise. * * @see #FLAG_SUPPORT_STATIC_TRANSFORMATIONS */ protected void setStaticTransformationsEnabled(boolean enabled) { setBooleanFlag(FLAG_SUPPORT_STATIC_TRANSFORMATIONS, enabled); } /** * {@inheritDoc} * * @see #setStaticTransformationsEnabled(boolean) */ protected boolean getChildStaticTransformation(View child, Transformation t) { return false; } /** * {@hide} */ @Override protected View findViewTraversal(int id) { if (id == mID) { return this; } final View[] where = mChildren; final int len = mChildrenCount; for (int i = 0; i < len; i++) { View v = where[i]; if ((v.mPrivateFlags & IS_ROOT_NAMESPACE) == 0) { v = v.findViewById(id); if (v != null) { return v; } } } return null; } /** * {@hide} */ @Override protected View findViewWithTagTraversal(Object tag) { if (tag != null && tag.equals(mTag)) { return this; } final View[] where = mChildren; final int len = mChildrenCount; for (int i = 0; i < len; i++) { View v = where[i]; if ((v.mPrivateFlags & IS_ROOT_NAMESPACE) == 0) { v = v.findViewWithTag(tag); if (v != null) { return v; } } } return null; } /** * Adds a child view. If no layout parameters are already set on the child, the * default parameters for this ViewGroup are set on the child. * * @param child the child view to add * * @see #generateDefaultLayoutParams() */ public void addView(View child) { addView(child, -1); } /** * Adds a child view. If no layout parameters are already set on the child, the * default parameters for this ViewGroup are set on the child. * * @param child the child view to add * @param index the position at which to add the child * * @see #generateDefaultLayoutParams() */ public void addView(View child, int index) { LayoutParams params = child.getLayoutParams(); if (params == null) { params = generateDefaultLayoutParams(); if (params == null) { throw new IllegalArgumentException("generateDefaultLayoutParams() cannot return null"); } } addView(child, index, params); } /** * Adds a child view with this ViewGroup's default layout parameters and the * specified width and height. * * @param child the child view to add */ public void addView(View child, int width, int height) { final LayoutParams params = generateDefaultLayoutParams(); params.width = width; params.height = height; addView(child, -1, params); } /** * Adds a child view with the specified layout parameters. * * @param child the child view to add * @param params the layout parameters to set on the child */ public void addView(View child, LayoutParams params) { addView(child, -1, params); } /** * Adds a child view with the specified layout parameters. * * @param child the child view to add * @param index the position at which to add the child * @param params the layout parameters to set on the child */ public void addView(View child, int index, LayoutParams params) { if (DBG) { System.out.println(this + " addView"); } // addViewInner() will call child.requestLayout() when setting the new LayoutParams // therefore, we call requestLayout() on ourselves before, so that the child's request // will be blocked at our level requestLayout(); invalidate(); addViewInner(child, index, params, false); } /** * {@inheritDoc} */ public void updateViewLayout(View view, ViewGroup.LayoutParams params) { if (!checkLayoutParams(params)) { throw new IllegalArgumentException("Invalid LayoutParams supplied to " + this); } if (view.mParent != this) { throw new IllegalArgumentException("Given view not a child of " + this); } view.setLayoutParams(params); } /** * {@inheritDoc} */ protected boolean checkLayoutParams(ViewGroup.LayoutParams p) { return p != null; } /** * Interface definition for a callback to be invoked when the hierarchy * within this view changed. The hierarchy changes whenever a child is added * to or removed from this view. */ public interface OnHierarchyChangeListener { /** * Called when a new child is added to a parent view. * * @param parent the view in which a child was added * @param child the new child view added in the hierarchy */ void onChildViewAdded(View parent, View child); /** * Called when a child is removed from a parent view. * * @param parent the view from which the child was removed * @param child the child removed from the hierarchy */ void onChildViewRemoved(View parent, View child); } /** * Register a callback to be invoked when a child is added to or removed * from this view. * * @param listener the callback to invoke on hierarchy change */ public void setOnHierarchyChangeListener(OnHierarchyChangeListener listener) { mOnHierarchyChangeListener = listener; } /** * Adds a view during layout. This is useful if in your onLayout() method, * you need to add more views (as does the list view for example). * * If index is negative, it means put it at the end of the list. * * @param child the view to add to the group * @param index the index at which the child must be added * @param params the layout parameters to associate with the child * @return true if the child was added, false otherwise */ protected boolean addViewInLayout(View child, int index, LayoutParams params) { return addViewInLayout(child, index, params, false); } /** * Adds a view during layout. This is useful if in your onLayout() method, * you need to add more views (as does the list view for example). * * If index is negative, it means put it at the end of the list. * * @param child the view to add to the group * @param index the index at which the child must be added * @param params the layout parameters to associate with the child * @param preventRequestLayout if true, calling this method will not trigger a * layout request on child * @return true if the child was added, false otherwise */ protected boolean addViewInLayout(View child, int index, LayoutParams params, boolean preventRequestLayout) { child.mParent = null; addViewInner(child, index, params, preventRequestLayout); child.mPrivateFlags |= DRAWN; return true; } /** * Prevents the specified child to be laid out during the next layout pass. * * @param child the child on which to perform the cleanup */ protected void cleanupLayoutState(View child) { child.mPrivateFlags &= ~View.FORCE_LAYOUT; } private void addViewInner(View child, int index, LayoutParams params, boolean preventRequestLayout) { if (child.getParent() != null) { throw new IllegalStateException("The specified child already has a parent. " + "You must call removeView() on the child's parent first."); } if (!checkLayoutParams(params)) { params = generateLayoutParams(params); } if (preventRequestLayout) { child.mLayoutParams = params; } else { child.setLayoutParams(params); } if (index < 0) { index = mChildrenCount; } addInArray(child, index); // tell our children if (preventRequestLayout) { child.assignParent(this); } else { child.mParent = this; } if (child.hasFocus()) { requestChildFocus(child, child.findFocus()); } AttachInfo ai = mAttachInfo; if (ai != null) { boolean lastKeepOn = ai.mKeepScreenOn; ai.mKeepScreenOn = false; child.dispatchAttachedToWindow(mAttachInfo, (mViewFlags&VISIBILITY_MASK)); if (ai.mKeepScreenOn) { needGlobalAttributesUpdate(true); } ai.mKeepScreenOn = lastKeepOn; } if (mOnHierarchyChangeListener != null) { mOnHierarchyChangeListener.onChildViewAdded(this, child); } if ((child.mViewFlags & DUPLICATE_PARENT_STATE) == DUPLICATE_PARENT_STATE) { mGroupFlags |= FLAG_NOTIFY_CHILDREN_ON_DRAWABLE_STATE_CHANGE; } } private void addInArray(View child, int index) { View[] children = mChildren; final int count = mChildrenCount; final int size = children.length; if (index == count) { if (size == count) { mChildren = new View[size + ARRAY_CAPACITY_INCREMENT]; System.arraycopy(children, 0, mChildren, 0, size); children = mChildren; } children[mChildrenCount++] = child; } else if (index < count) { if (size == count) { mChildren = new View[size + ARRAY_CAPACITY_INCREMENT]; System.arraycopy(children, 0, mChildren, 0, index); System.arraycopy(children, index, mChildren, index + 1, count - index); children = mChildren; } else { System.arraycopy(children, index, children, index + 1, count - index); } children[index] = child; mChildrenCount++; } else { throw new IndexOutOfBoundsException("index=" + index + " count=" + count); } } // This method also sets the child's mParent to null private void removeFromArray(int index) { final View[] children = mChildren; children[index].mParent = null; final int count = mChildrenCount; if (index == count - 1) { children[--mChildrenCount] = null; } else if (index >= 0 && index < count) { System.arraycopy(children, index + 1, children, index, count - index - 1); children[--mChildrenCount] = null; } else { throw new IndexOutOfBoundsException(); } } // This method also sets the children's mParent to null private void removeFromArray(int start, int count) { final View[] children = mChildren; final int childrenCount = mChildrenCount; start = Math.max(0, start); final int end = Math.min(childrenCount, start + count); if (start == end) { return; } if (end == childrenCount) { for (int i = start; i < end; i++) { children[i].mParent = null; children[i] = null; } } else { for (int i = start; i < end; i++) { children[i].mParent = null; } // Since we're looping above, we might as well do the copy, but is arraycopy() // faster than the extra 2 bounds checks we would do in the loop? System.arraycopy(children, end, children, start, childrenCount - end); for (int i = childrenCount - (end - start); i < childrenCount; i++) { children[i] = null; } } mChildrenCount -= (end - start); } private void bindLayoutAnimation(View child) { Animation a = mLayoutAnimationController.getAnimationForView(child); child.setAnimation(a); } /** * Subclasses should override this method to set layout animation * parameters on the supplied child. * * @param child the child to associate with animation parameters * @param params the child's layout parameters which hold the animation * parameters * @param index the index of the child in the view group * @param count the number of children in the view group */ protected void attachLayoutAnimationParameters(View child, LayoutParams params, int index, int count) { LayoutAnimationController.AnimationParameters animationParams = params.layoutAnimationParameters; if (animationParams == null) { animationParams = new LayoutAnimationController.AnimationParameters(); params.layoutAnimationParameters = animationParams; } animationParams.count = count; animationParams.index = index; } /** * {@inheritDoc} */ public void removeView(View view) { removeViewInternal(view); requestLayout(); invalidate(); } /** * Removes a view during layout. This is useful if in your onLayout() method, * you need to remove more views. * * @param view the view to remove from the group */ public void removeViewInLayout(View view) { removeViewInternal(view); } /** * Removes a range of views during layout. This is useful if in your onLayout() method, * you need to remove more views. * * @param start the index of the first view to remove from the group * @param count the number of views to remove from the group */ public void removeViewsInLayout(int start, int count) { removeViewsInternal(start, count); } /** * Removes the view at the specified position in the group. * * @param index the position in the group of the view to remove */ public void removeViewAt(int index) { removeViewInternal(index, getChildAt(index)); requestLayout(); invalidate(); } /** * Removes the specified range of views from the group. * * @param start the first position in the group of the range of views to remove * @param count the number of views to remove */ public void removeViews(int start, int count) { removeViewsInternal(start, count); requestLayout(); invalidate(); } private void removeViewInternal(View view) { final int index = indexOfChild(view); if (index >= 0) { removeViewInternal(index, view); } } private void removeViewInternal(int index, View view) { boolean clearChildFocus = false; if (view == mFocused) { view.clearFocusForRemoval(); clearChildFocus = true; } if (view.getAnimation() != null) { addDisappearingView(view); } else if (view.mAttachInfo != null) { view.dispatchDetachedFromWindow(); } if (mOnHierarchyChangeListener != null) { mOnHierarchyChangeListener.onChildViewRemoved(this, view); } needGlobalAttributesUpdate(false); removeFromArray(index); if (clearChildFocus) { clearChildFocus(view); } } private void removeViewsInternal(int start, int count) { final OnHierarchyChangeListener onHierarchyChangeListener = mOnHierarchyChangeListener; final boolean notifyListener = onHierarchyChangeListener != null; final View focused = mFocused; final boolean detach = mAttachInfo != null; View clearChildFocus = null; final View[] children = mChildren; final int end = start + count; for (int i = start; i < end; i++) { final View view = children[i]; if (view == focused) { view.clearFocusForRemoval(); clearChildFocus = view; } if (view.getAnimation() != null) { addDisappearingView(view); } else if (detach) { view.dispatchDetachedFromWindow(); } needGlobalAttributesUpdate(false); if (notifyListener) { onHierarchyChangeListener.onChildViewRemoved(this, view); } } removeFromArray(start, count); if (clearChildFocus != null) { clearChildFocus(clearChildFocus); } } /** * Call this method to remove all child views from the * ViewGroup. */ public void removeAllViews() { removeAllViewsInLayout(); requestLayout(); invalidate(); } /** * Called by a ViewGroup subclass to remove child views from itself, * when it must first know its size on screen before it can calculate how many * child views it will render. An example is a Gallery or a ListView, which * may "have" 50 children, but actually only render the number of children * that can currently fit inside the object on screen. Do not call * this method unless you are extending ViewGroup and understand the * view measuring and layout pipeline. */ public void removeAllViewsInLayout() { final int count = mChildrenCount; if (count <= 0) { return; } final View[] children = mChildren; mChildrenCount = 0; final OnHierarchyChangeListener listener = mOnHierarchyChangeListener; final boolean notify = listener != null; final View focused = mFocused; final boolean detach = mAttachInfo != null; View clearChildFocus = null; needGlobalAttributesUpdate(false); for (int i = count - 1; i >= 0; i--) { final View view = children[i]; if (view == focused) { view.clearFocusForRemoval(); clearChildFocus = view; } if (view.getAnimation() != null) { addDisappearingView(view); } else if (detach) { view.dispatchDetachedFromWindow(); } if (notify) { listener.onChildViewRemoved(this, view); } view.mParent = null; children[i] = null; } if (clearChildFocus != null) { clearChildFocus(clearChildFocus); } } /** * Finishes the removal of a detached view. This method will dispatch the detached from * window event and notify the hierarchy change listener. * * @param child the child to be definitely removed from the view hierarchy * @param animate if true and the view has an animation, the view is placed in the * disappearing views list, otherwise, it is detached from the window * * @see #attachViewToParent(View, int, android.view.ViewGroup.LayoutParams) * @see #detachAllViewsFromParent() * @see #detachViewFromParent(View) * @see #detachViewFromParent(int) */ protected void removeDetachedView(View child, boolean animate) { if (child == mFocused) { child.clearFocus(); } if (animate && child.getAnimation() != null) { addDisappearingView(child); } else if (child.mAttachInfo != null) { child.dispatchDetachedFromWindow(); } if (mOnHierarchyChangeListener != null) { mOnHierarchyChangeListener.onChildViewRemoved(this, child); } } /** * Attaches a view to this view group. Attaching a view assigns this group as the parent, * sets the layout parameters and puts the view in the list of children so it can be retrieved * by calling {@link #getChildAt(int)}. * * This method should be called only for view which were detached from their parent. * * @param child the child to attach * @param index the index at which the child should be attached * @param params the layout parameters of the child * * @see #removeDetachedView(View, boolean) * @see #detachAllViewsFromParent() * @see #detachViewFromParent(View) * @see #detachViewFromParent(int) */ protected void attachViewToParent(View child, int index, LayoutParams params) { child.mLayoutParams = params; if (index < 0) { index = mChildrenCount; } addInArray(child, index); child.mParent = this; child.mPrivateFlags |= DRAWN; if (child.hasFocus()) { requestChildFocus(child, child.findFocus()); } } /** * Detaches a view from its parent. Detaching a view should be temporary and followed * either by a call to {@link #attachViewToParent(View, int, android.view.ViewGroup.LayoutParams)} * or a call to {@link #removeDetachedView(View, boolean)}. When a view is detached, * its parent is null and cannot be retrieved by a call to {@link #getChildAt(int)}. * * @param child the child to detach * * @see #detachViewFromParent(int) * @see #detachViewsFromParent(int, int) * @see #detachAllViewsFromParent() * @see #attachViewToParent(View, int, android.view.ViewGroup.LayoutParams) * @see #removeDetachedView(View, boolean) */ protected void detachViewFromParent(View child) { removeFromArray(indexOfChild(child)); } /** * Detaches a view from its parent. Detaching a view should be temporary and followed * either by a call to {@link #attachViewToParent(View, int, android.view.ViewGroup.LayoutParams)} * or a call to {@link #removeDetachedView(View, boolean)}. When a view is detached, * its parent is null and cannot be retrieved by a call to {@link #getChildAt(int)}. * * @param index the index of the child to detach * * @see #detachViewFromParent(View) * @see #detachAllViewsFromParent() * @see #detachViewsFromParent(int, int) * @see #attachViewToParent(View, int, android.view.ViewGroup.LayoutParams) * @see #removeDetachedView(View, boolean) */ protected void detachViewFromParent(int index) { removeFromArray(index); } /** * Detaches a range of view from their parent. Detaching a view should be temporary and followed * either by a call to {@link #attachViewToParent(View, int, android.view.ViewGroup.LayoutParams)} * or a call to {@link #removeDetachedView(View, boolean)}. When a view is detached, its * parent is null and cannot be retrieved by a call to {@link #getChildAt(int)}. * * @param start the first index of the childrend range to detach * @param count the number of children to detach * * @see #detachViewFromParent(View) * @see #detachViewFromParent(int) * @see #detachAllViewsFromParent() * @see #attachViewToParent(View, int, android.view.ViewGroup.LayoutParams) * @see #removeDetachedView(View, boolean) */ protected void detachViewsFromParent(int start, int count) { removeFromArray(start, count); } /** * Detaches all views from the parent. Detaching a view should be temporary and followed * either by a call to {@link #attachViewToParent(View, int, android.view.ViewGroup.LayoutParams)} * or a call to {@link #removeDetachedView(View, boolean)}. When a view is detached, * its parent is null and cannot be retrieved by a call to {@link #getChildAt(int)}. * * @see #detachViewFromParent(View) * @see #detachViewFromParent(int) * @see #detachViewsFromParent(int, int) * @see #attachViewToParent(View, int, android.view.ViewGroup.LayoutParams) * @see #removeDetachedView(View, boolean) */ protected void detachAllViewsFromParent() { final int count = mChildrenCount; if (count <= 0) { return; } final View[] children = mChildren; mChildrenCount = 0; for (int i = count - 1; i >= 0; i--) { children[i].mParent = null; children[i] = null; } } /** * Don't call or override this method. It is used for the implementation of * the view hierarchy. */ public final void invalidateChild(View child, final Rect dirty) { if (ViewDebug.TRACE_HIERARCHY) { ViewDebug.trace(this, ViewDebug.HierarchyTraceType.INVALIDATE_CHILD); } ViewParent parent = this; final AttachInfo attachInfo = mAttachInfo; if (attachInfo != null) { final int[] location = attachInfo.mInvalidateChildLocation; location[CHILD_LEFT_INDEX] = child.mLeft; location[CHILD_TOP_INDEX] = child.mTop; // If the child is drawing an animation, we want to copy this flag onto // ourselves and the parent to make sure the invalidate request goes // through final boolean drawAnimation = (child.mPrivateFlags & DRAW_ANIMATION) == DRAW_ANIMATION; do { if (drawAnimation) { if (parent instanceof View) { ((View) parent).mPrivateFlags |= DRAW_ANIMATION; } else if (parent instanceof ViewRoot) { ((ViewRoot) parent).mIsAnimating = true; } } parent = parent.invalidateChildInParent(location, dirty); } while (parent != null); } } /** * Don't call or override this method. It is used for the implementation of * the view hierarchy. * * This implementation returns null if this ViewGroup does not have a parent, * if this ViewGroup is already fully invalidated or if the dirty rectangle * does not intersect with this ViewGroup's bounds. */ public ViewParent invalidateChildInParent(final int[] location, final Rect dirty) { if (ViewDebug.TRACE_HIERARCHY) { ViewDebug.trace(this, ViewDebug.HierarchyTraceType.INVALIDATE_CHILD_IN_PARENT); } if ((mPrivateFlags & DRAWN) == DRAWN) { if ((mGroupFlags & (FLAG_OPTIMIZE_INVALIDATE | FLAG_ANIMATION_DONE)) != FLAG_OPTIMIZE_INVALIDATE) { dirty.offset(location[CHILD_LEFT_INDEX] - mScrollX, location[CHILD_TOP_INDEX] - mScrollY); final int left = mLeft; final int top = mTop; if (dirty.intersect(0, 0, mRight - left, mBottom - top) || (mPrivateFlags & DRAW_ANIMATION) == DRAW_ANIMATION) { mPrivateFlags &= ~DRAWING_CACHE_VALID; location[CHILD_LEFT_INDEX] = left; location[CHILD_TOP_INDEX] = top; return mParent; } } else { mPrivateFlags &= ~DRAWN & ~DRAWING_CACHE_VALID; location[CHILD_LEFT_INDEX] = mLeft; location[CHILD_TOP_INDEX] = mTop; dirty.set(0, 0, mRight - location[CHILD_LEFT_INDEX], mBottom - location[CHILD_TOP_INDEX]); return mParent; } } return null; } /** * Offset a rectangle that is in a descendant's coordinate * space into our coordinate space. * @param descendant A descendant of this view * @param rect A rectangle defined in descendant's coordinate space. */ public final void offsetDescendantRectToMyCoords(View descendant, Rect rect) { offsetRectBetweenParentAndChild(descendant, rect, true, false); } /** * Offset a rectangle that is in our coordinate space into an ancestor's * coordinate space. * @param descendant A descendant of this view * @param rect A rectangle defined in descendant's coordinate space. */ public final void offsetRectIntoDescendantCoords(View descendant, Rect rect) { offsetRectBetweenParentAndChild(descendant, rect, false, false); } /** * Helper method that offsets a rect either from parent to descendant or * descendant to parent. */ void offsetRectBetweenParentAndChild(View descendant, Rect rect, boolean offsetFromChildToParent, boolean clipToBounds) { // already in the same coord system :) if (descendant == this) { return; } ViewParent theParent = descendant.mParent; // search and offset up to the parent while ((theParent != null) && (theParent instanceof View) && (theParent != this)) { if (offsetFromChildToParent) { rect.offset(descendant.mLeft - descendant.mScrollX, descendant.mTop - descendant.mScrollY); if (clipToBounds) { View p = (View) theParent; rect.intersect(0, 0, p.mRight - p.mLeft, p.mBottom - p.mTop); } } else { if (clipToBounds) { View p = (View) theParent; rect.intersect(0, 0, p.mRight - p.mLeft, p.mBottom - p.mTop); } rect.offset(descendant.mScrollX - descendant.mLeft, descendant.mScrollY - descendant.mTop); } descendant = (View) theParent; theParent = descendant.mParent; } // now that we are up to this view, need to offset one more time // to get into our coordinate space if (theParent == this) { if (offsetFromChildToParent) { rect.offset(descendant.mLeft - descendant.mScrollX, descendant.mTop - descendant.mScrollY); } else { rect.offset(descendant.mScrollX - descendant.mLeft, descendant.mScrollY - descendant.mTop); } } else { throw new IllegalArgumentException("parameter must be a descendant of this view"); } } /** * Offset the vertical location of all children of this view by the specified number of pixels. * * @param offset the number of pixels to offset * * @hide */ public void offsetChildrenTopAndBottom(int offset) { final int count = mChildrenCount; final View[] children = mChildren; for (int i = 0; i < count; i++) { final View v = children[i]; v.mTop += offset; v.mBottom += offset; } } /** * {@inheritDoc} */ public boolean getChildVisibleRect(View child, Rect r, android.graphics.Point offset) { int dx = child.mLeft - mScrollX; int dy = child.mTop - mScrollY; if (offset != null) { offset.x += dx; offset.y += dy; } r.offset(dx, dy); return r.intersect(0, 0, mRight - mLeft, mBottom - mTop) && (mParent == null || mParent.getChildVisibleRect(this, r, offset)); } /** * {@inheritDoc} */ @Override protected abstract void onLayout(boolean changed, int l, int t, int r, int b); /** * Indicates whether the view group has the ability to animate its children * after the first layout. * * @return true if the children can be animated, false otherwise */ protected boolean canAnimate() { return mLayoutAnimationController != null; } /** * Runs the layout animation. Calling this method triggers a relayout of * this view group. */ public void startLayoutAnimation() { if (mLayoutAnimationController != null) { mGroupFlags |= FLAG_RUN_ANIMATION; requestLayout(); } } /** * Schedules the layout animation to be played after the next layout pass * of this view group. This can be used to restart the layout animation * when the content of the view group changes or when the activity is * paused and resumed. */ public void scheduleLayoutAnimation() { mGroupFlags |= FLAG_RUN_ANIMATION; } /** * Sets the layout animation controller used to animate the group's * children after the first layout. * * @param controller the animation controller */ public void setLayoutAnimation(LayoutAnimationController controller) { mLayoutAnimationController = controller; if (mLayoutAnimationController != null) { mGroupFlags |= FLAG_RUN_ANIMATION; } } /** * Returns the layout animation controller used to animate the group's * children. * * @return the current animation controller */ public LayoutAnimationController getLayoutAnimation() { return mLayoutAnimationController; } /** * Indicates whether the children's drawing cache is used during a layout * animation. By default, the drawing cache is enabled but this will prevent * nested layout animations from working. To nest animations, you must disable * the cache. * * @return true if the animation cache is enabled, false otherwise * * @see #setAnimationCacheEnabled(boolean) * @see View#setDrawingCacheEnabled(boolean) */ @ViewDebug.ExportedProperty public boolean isAnimationCacheEnabled() { return (mGroupFlags & FLAG_ANIMATION_CACHE) == FLAG_ANIMATION_CACHE; } /** * Enables or disables the children's drawing cache during a layout animation. * By default, the drawing cache is enabled but this will prevent nested * layout animations from working. To nest animations, you must disable the * cache. * * @param enabled true to enable the animation cache, false otherwise * * @see #isAnimationCacheEnabled() * @see View#setDrawingCacheEnabled(boolean) */ public void setAnimationCacheEnabled(boolean enabled) { setBooleanFlag(FLAG_ANIMATION_CACHE, enabled); } /** * Indicates whether this ViewGroup will always try to draw its children using their * drawing cache. By default this property is enabled. * * @return true if the animation cache is enabled, false otherwise * * @see #setAlwaysDrawnWithCacheEnabled(boolean) * @see #setChildrenDrawnWithCacheEnabled(boolean) * @see View#setDrawingCacheEnabled(boolean) */ @ViewDebug.ExportedProperty public boolean isAlwaysDrawnWithCacheEnabled() { return (mGroupFlags & FLAG_ALWAYS_DRAWN_WITH_CACHE) == FLAG_ALWAYS_DRAWN_WITH_CACHE; } /** * Indicates whether this ViewGroup will always try to draw its children using their * drawing cache. This property can be set to true when the cache rendering is * slightly different from the children's normal rendering. Renderings can be different, * for instance, when the cache's quality is set to low. * * When this property is disabled, the ViewGroup will use the drawing cache of its * children only when asked to. It's usually the task of subclasses to tell ViewGroup * when to start using the drawing cache and when to stop using it. * * @param always true to always draw with the drawing cache, false otherwise * * @see #isAlwaysDrawnWithCacheEnabled() * @see #setChildrenDrawnWithCacheEnabled(boolean) * @see View#setDrawingCacheEnabled(boolean) * @see View#setDrawingCacheQuality(int) */ public void setAlwaysDrawnWithCacheEnabled(boolean always) { setBooleanFlag(FLAG_ALWAYS_DRAWN_WITH_CACHE, always); } /** * Indicates whether the ViewGroup is currently drawing its children using * their drawing cache. * * @return true if children should be drawn with their cache, false otherwise * * @see #setAlwaysDrawnWithCacheEnabled(boolean) * @see #setChildrenDrawnWithCacheEnabled(boolean) */ @ViewDebug.ExportedProperty protected boolean isChildrenDrawnWithCacheEnabled() { return (mGroupFlags & FLAG_CHILDREN_DRAWN_WITH_CACHE) == FLAG_CHILDREN_DRAWN_WITH_CACHE; } /** * Tells the ViewGroup to draw its children using their drawing cache. This property * is ignored when {@link #isAlwaysDrawnWithCacheEnabled()} is true. A child's drawing cache * will be used only if it has been enabled. * * Subclasses should call this method to start and stop using the drawing cache when * they perform performance sensitive operations, like scrolling or animating. * * @param enabled true if children should be drawn with their cache, false otherwise * * @see #setAlwaysDrawnWithCacheEnabled(boolean) * @see #isChildrenDrawnWithCacheEnabled() */ protected void setChildrenDrawnWithCacheEnabled(boolean enabled) { setBooleanFlag(FLAG_CHILDREN_DRAWN_WITH_CACHE, enabled); } private void setBooleanFlag(int flag, boolean value) { if (value) { mGroupFlags |= flag; } else { mGroupFlags &= ~flag; } } /** * Returns an integer indicating what types of drawing caches are kept in memory. * * @see #setPersistentDrawingCache(int) * @see #setAnimationCacheEnabled(boolean) * * @return one or a combination of {@link #PERSISTENT_NO_CACHE}, * {@link #PERSISTENT_ANIMATION_CACHE}, {@link #PERSISTENT_SCROLLING_CACHE} * and {@link #PERSISTENT_ALL_CACHES} */ @ViewDebug.ExportedProperty(mapping = { @ViewDebug.IntToString(from = PERSISTENT_NO_CACHE, to = "NONE"), @ViewDebug.IntToString(from = PERSISTENT_ALL_CACHES, to = "ANIMATION"), @ViewDebug.IntToString(from = PERSISTENT_SCROLLING_CACHE, to = "SCROLLING"), @ViewDebug.IntToString(from = PERSISTENT_ALL_CACHES, to = "ALL") }) public int getPersistentDrawingCache() { return mPersistentDrawingCache; } /** * Indicates what types of drawing caches should be kept in memory after * they have been created. * * @see #getPersistentDrawingCache() * @see #setAnimationCacheEnabled(boolean) * * @param drawingCacheToKeep one or a combination of {@link #PERSISTENT_NO_CACHE}, * {@link #PERSISTENT_ANIMATION_CACHE}, {@link #PERSISTENT_SCROLLING_CACHE} * and {@link #PERSISTENT_ALL_CACHES} */ public void setPersistentDrawingCache(int drawingCacheToKeep) { mPersistentDrawingCache = drawingCacheToKeep & PERSISTENT_ALL_CACHES; } /** * Returns a new set of layout parameters based on the supplied attributes set. * * @param attrs the attributes to build the layout parameters from * * @return an instance of {@link android.view.ViewGroup.LayoutParams} or one * of its descendants */ public LayoutParams generateLayoutParams(AttributeSet attrs) { return new LayoutParams(getContext(), attrs); } /** * Returns a safe set of layout parameters based on the supplied layout params. * When a ViewGroup is passed a View whose layout params do not pass the test of * {@link #checkLayoutParams(android.view.ViewGroup.LayoutParams)}, this method * is invoked. This method should return a new set of layout params suitable for * this ViewGroup, possibly by copying the appropriate attributes from the * specified set of layout params. * * @param p The layout parameters to convert into a suitable set of layout parameters * for this ViewGroup. * * @return an instance of {@link android.view.ViewGroup.LayoutParams} or one * of its descendants */ protected LayoutParams generateLayoutParams(ViewGroup.LayoutParams p) { return p; } /** * Returns a set of default layout parameters. These parameters are requested * when the View passed to {@link #addView(View)} has no layout parameters * already set. If null is returned, an exception is thrown from addView. * * @return a set of default layout parameters or null */ protected LayoutParams generateDefaultLayoutParams() { return new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT); } /** * {@inheritDoc} */ @Override protected void debug(int depth) { super.debug(depth); String output; if (mFocused != null) { output = debugIndent(depth); output += "mFocused"; Log.d(VIEW_LOG_TAG, output); } if (mChildrenCount != 0) { output = debugIndent(depth); output += "{"; Log.d(VIEW_LOG_TAG, output); } int count = mChildrenCount; for (int i = 0; i < count; i++) { View child = mChildren[i]; child.debug(depth + 1); } if (mChildrenCount != 0) { output = debugIndent(depth); output += "}"; Log.d(VIEW_LOG_TAG, output); } } /** * Returns the position in the group of the specified child view. * * @param child the view for which to get the position * @return a positive integer representing the position of the view in the * group, or -1 if the view does not exist in the group */ public int indexOfChild(View child) { final int count = mChildrenCount; final View[] children = mChildren; for (int i = 0; i < count; i++) { if (children[i] == child) { return i; } } return -1; } /** * Returns the number of children in the group. * * @return a positive integer representing the number of children in * the group */ public int getChildCount() { return mChildrenCount; } /** * Returns the view at the specified position in the group. * * @param index the position at which to get the view from * @return the view at the specified position or null if the position * does not exist within the group */ public View getChildAt(int index) { try { return mChildren[index]; } catch (IndexOutOfBoundsException ex) { return null; } } /** * Ask all of the children of this view to measure themselves, taking into * account both the MeasureSpec requirements for this view and its padding. * We skip children that are in the GONE state The heavy lifting is done in * getChildMeasureSpec. * * @param widthMeasureSpec The width requirements for this view * @param heightMeasureSpec The height requirements for this view */ protected void measureChildren(int widthMeasureSpec, int heightMeasureSpec) { final int size = mChildrenCount; final View[] children = mChildren; for (int i = 0; i < size; ++i) { final View child = children[i]; if ((child.mViewFlags & VISIBILITY_MASK) != GONE) { measureChild(child, widthMeasureSpec, heightMeasureSpec); } } } /** * Ask one of the children of this view to measure itself, taking into * account both the MeasureSpec requirements for this view and its padding. * The heavy lifting is done in getChildMeasureSpec. * * @param child The child to measure * @param parentWidthMeasureSpec The width requirements for this view * @param parentHeightMeasureSpec The height requirements for this view */ protected void measureChild(View child, int parentWidthMeasureSpec, int parentHeightMeasureSpec) { final LayoutParams lp = child.getLayoutParams(); final int childWidthMeasureSpec = getChildMeasureSpec(parentWidthMeasureSpec, mPaddingLeft + mPaddingRight, lp.width); final int childHeightMeasureSpec = getChildMeasureSpec(parentHeightMeasureSpec, mPaddingTop + mPaddingBottom, lp.height); child.measure(childWidthMeasureSpec, childHeightMeasureSpec); } /** * Ask one of the children of this view to measure itself, taking into * account both the MeasureSpec requirements for this view and its padding * and margins. The child must have MarginLayoutParams The heavy lifting is * done in getChildMeasureSpec. * * @param child The child to measure * @param parentWidthMeasureSpec The width requirements for this view * @param widthUsed Extra space that has been used up by the parent * horizontally (possibly by other children of the parent) * @param parentHeightMeasureSpec The height requirements for this view * @param heightUsed Extra space that has been used up by the parent * vertically (possibly by other children of the parent) */ protected void measureChildWithMargins(View child, int parentWidthMeasureSpec, int widthUsed, int parentHeightMeasureSpec, int heightUsed) { final MarginLayoutParams lp = (MarginLayoutParams) child.getLayoutParams(); final int childWidthMeasureSpec = getChildMeasureSpec(parentWidthMeasureSpec, mPaddingLeft + mPaddingRight + lp.leftMargin + lp.rightMargin + widthUsed, lp.width); final int childHeightMeasureSpec = getChildMeasureSpec(parentHeightMeasureSpec, mPaddingTop + mPaddingBottom + lp.topMargin + lp.bottomMargin + heightUsed, lp.height); child.measure(childWidthMeasureSpec, childHeightMeasureSpec); } /** * Does the hard part of measureChildren: figuring out the MeasureSpec to * pass to a particular child. This method figures out the right MeasureSpec * for one dimension (height or width) of one child view. * * The goal is to combine information from our MeasureSpec with the * LayoutParams of the child to get the best possible results. For example, * if the this view knows its size (because its MeasureSpec has a mode of * EXACTLY), and the child has indicated in its LayoutParams that it wants * to be the same size as the parent, the parent should ask the child to * layout given an exact size. * * @param spec The requirements for this view * @param padding The padding of this view for the current dimension and * margins, if applicable * @param childDimension How big the child wants to be in the current * dimension * @return a MeasureSpec integer for the child */ public static int getChildMeasureSpec(int spec, int padding, int childDimension) { int specMode = MeasureSpec.getMode(spec); int specSize = MeasureSpec.getSize(spec); int size = Math.max(0, specSize - padding); int resultSize = 0; int resultMode = 0; switch (specMode) { // Parent has imposed an exact size on us case MeasureSpec.EXACTLY: if (childDimension >= 0) { resultSize = childDimension; resultMode = MeasureSpec.EXACTLY; } else if (childDimension == LayoutParams.FILL_PARENT) { // Child wants to be our size. So be it. resultSize = size; resultMode = MeasureSpec.EXACTLY; } else if (childDimension == LayoutParams.WRAP_CONTENT) { // Child wants to determine its own size. It can't be // bigger than us. resultSize = size; resultMode = MeasureSpec.AT_MOST; } break; // Parent has imposed a maximum size on us case MeasureSpec.AT_MOST: if (childDimension >= 0) { // Child wants a specific size... so be it resultSize = childDimension; resultMode = MeasureSpec.EXACTLY; } else if (childDimension == LayoutParams.FILL_PARENT) { // Child wants to be our size, but our size is not fixed. // Constrain child to not be bigger than us. resultSize = size; resultMode = MeasureSpec.AT_MOST; } else if (childDimension == LayoutParams.WRAP_CONTENT) { // Child wants to determine its own size. It can't be // bigger than us. resultSize = size; resultMode = MeasureSpec.AT_MOST; } break; // Parent asked to see how big we want to be case MeasureSpec.UNSPECIFIED: if (childDimension >= 0) { // Child wants a specific size... let him have it resultSize = childDimension; resultMode = MeasureSpec.EXACTLY; } else if (childDimension == LayoutParams.FILL_PARENT) { // Child wants to be our size... find out how big it should // be resultSize = 0; resultMode = MeasureSpec.UNSPECIFIED; } else if (childDimension == LayoutParams.WRAP_CONTENT) { // Child wants to determine its own size.... find out how // big it should be resultSize = 0; resultMode = MeasureSpec.UNSPECIFIED; } break; } return MeasureSpec.makeMeasureSpec(resultSize, resultMode); } /** * Removes any pending animations for views that have been removed. Call * this if you don't want animations for exiting views to stack up. */ public void clearDisappearingChildren() { if (mDisappearingChildren != null) { mDisappearingChildren.clear(); } } /** * Add a view which is removed from mChildren but still needs animation * * @param v View to add */ private void addDisappearingView(View v) { ArrayList<View> disappearingChildren = mDisappearingChildren; if (disappearingChildren == null) { disappearingChildren = mDisappearingChildren = new ArrayList<View>(); } disappearingChildren.add(v); } /** * Cleanup a view when its animation is done. This may mean removing it from * the list of disappearing views. * * @param view The view whose animation has finished * @param animation The animation, cannot be null */ private void finishAnimatingView(final View view, Animation animation) { final ArrayList<View> disappearingChildren = mDisappearingChildren; if (disappearingChildren != null) { if (disappearingChildren.contains(view)) { disappearingChildren.remove(view); if (view.mAttachInfo != null) { view.dispatchDetachedFromWindow(); } view.clearAnimation(); mGroupFlags |= FLAG_INVALIDATE_REQUIRED; } } if (animation != null && !animation.getFillAfter()) { view.clearAnimation(); } if ((view.mPrivateFlags & ANIMATION_STARTED) == ANIMATION_STARTED) { view.onAnimationEnd(); // Should be performed by onAnimationEnd() but this avoid an infinite loop, // so we'd rather be safe than sorry view.mPrivateFlags &= ~ANIMATION_STARTED; // Draw one more frame after the animation is done mGroupFlags |= FLAG_INVALIDATE_REQUIRED; } } /** * {@inheritDoc} */ @Override public boolean gatherTransparentRegion(Region region) { // If no transparent regions requested, we are always opaque. final boolean meOpaque = (mPrivateFlags & View.REQUEST_TRANSPARENT_REGIONS) == 0; if (meOpaque && region == null) { // The caller doesn't care about the region, so stop now. return true; } super.gatherTransparentRegion(region); final View[] children = mChildren; final int count = mChildrenCount; boolean noneOfTheChildrenAreTransparent = true; for (int i = 0; i < count; i++) { final View child = children[i]; if ((child.mViewFlags & VISIBILITY_MASK) != GONE || child.getAnimation() != null) { if (!child.gatherTransparentRegion(region)) { noneOfTheChildrenAreTransparent = false; } } } return meOpaque || noneOfTheChildrenAreTransparent; } /** * {@inheritDoc} */ public void requestTransparentRegion(View child) { if (child != null) { child.mPrivateFlags |= View.REQUEST_TRANSPARENT_REGIONS; if (mParent != null) { mParent.requestTransparentRegion(this); } } } @Override protected boolean fitSystemWindows(Rect insets) { boolean done = super.fitSystemWindows(insets); if (!done) { final int count = mChildrenCount; final View[] children = mChildren; for (int i = 0; i < count; i++) { done = children[i].fitSystemWindows(insets); if (done) { break; } } } return done; } /** * Returns the animation listener to which layout animation events are * sent. * * @return an {@link android.view.animation.Animation.AnimationListener} */ public Animation.AnimationListener getLayoutAnimationListener() { return mAnimationListener; } @Override protected void drawableStateChanged() { super.drawableStateChanged(); if ((mGroupFlags & FLAG_NOTIFY_CHILDREN_ON_DRAWABLE_STATE_CHANGE) != 0) { if ((mGroupFlags & FLAG_ADD_STATES_FROM_CHILDREN) != 0) { throw new IllegalStateException("addStateFromChildren cannot be enabled if a" + " child has duplicateParentState set to true"); } final View[] children = mChildren; final int count = mChildrenCount; for (int i = 0; i < count; i++) { final View child = children[i]; if ((child.mViewFlags & DUPLICATE_PARENT_STATE) != 0) { child.refreshDrawableState(); } } } } @Override protected int[] onCreateDrawableState(int extraSpace) { if ((mGroupFlags & FLAG_ADD_STATES_FROM_CHILDREN) == 0) { return super.onCreateDrawableState(extraSpace); } int need = 0; int n = getChildCount(); for (int i = 0; i < n; i++) { int[] childState = getChildAt(i).getDrawableState(); if (childState != null) { need += childState.length; } } int[] state = super.onCreateDrawableState(extraSpace + need); for (int i = 0; i < n; i++) { int[] childState = getChildAt(i).getDrawableState(); if (childState != null) { state = mergeDrawableStates(state, childState); } } return state; } /** * Sets whether this ViewGroup's drawable states also include * its children's drawable states. This is used, for example, to * make a group appear to be focused when its child EditText or button * is focused. */ public void setAddStatesFromChildren(boolean addsStates) { if (addsStates) { mGroupFlags |= FLAG_ADD_STATES_FROM_CHILDREN; } else { mGroupFlags &= ~FLAG_ADD_STATES_FROM_CHILDREN; } refreshDrawableState(); } /** * Returns whether this ViewGroup's drawable states also include * its children's drawable states. This is used, for example, to * make a group appear to be focused when its child EditText or button * is focused. */ public boolean addStatesFromChildren() { return (mGroupFlags & FLAG_ADD_STATES_FROM_CHILDREN) != 0; } /** * If {link #addStatesFromChildren} is true, refreshes this group's * drawable state (to include the states from its children). */ public void childDrawableStateChanged(View child) { if ((mGroupFlags & FLAG_ADD_STATES_FROM_CHILDREN) != 0) { refreshDrawableState(); } } /** * Specifies the animation listener to which layout animation events must * be sent. Only * {@link android.view.animation.Animation.AnimationListener#onAnimationStart(Animation)} * and * {@link android.view.animation.Animation.AnimationListener#onAnimationEnd(Animation)} * are invoked. * * @param animationListener the layout animation listener */ public void setLayoutAnimationListener(Animation.AnimationListener animationListener) { mAnimationListener = animationListener; } /** * LayoutParams are used by views to tell their parents how they want to be * laid out. See * {@link android.R.styleable#ViewGroup_Layout ViewGroup Layout Attributes} * for a list of all child view attributes that this class supports. * * <p> * The base LayoutParams class just describes how big the view wants to be * for both width and height. For each dimension, it can specify one of: * <ul> * <li> an exact number * <li>FILL_PARENT, which means the view wants to be as big as its parent * (minus padding) * <li> WRAP_CONTENT, which means that the view wants to be just big enough * to enclose its content (plus padding) * </ul> * There are subclasses of LayoutParams for different subclasses of * ViewGroup. For example, AbsoluteLayout has its own subclass of * LayoutParams which adds an X and Y value. * * @attr ref android.R.styleable#ViewGroup_Layout_layout_height * @attr ref android.R.styleable#ViewGroup_Layout_layout_width */ public static class LayoutParams { /** * Special value for the height or width requested by a View. * FILL_PARENT means that the view wants to fill the available space * within the parent, taking the parent's padding into account. */ public static final int FILL_PARENT = -1; /** * Special value for the height or width requested by a View. * WRAP_CONTENT means that the view wants to be just large enough to fit * its own internal content, taking its own padding into account. */ public static final int WRAP_CONTENT = -2; /** * Information about how wide the view wants to be. Can be an exact * size, or one of the constants FILL_PARENT or WRAP_CONTENT. */ @ViewDebug.ExportedProperty(mapping = { @ViewDebug.IntToString(from = FILL_PARENT, to = "FILL_PARENT"), @ViewDebug.IntToString(from = WRAP_CONTENT, to = "WRAP_CONTENT") }) public int width; /** * Information about how tall the view wants to be. Can be an exact * size, or one of the constants FILL_PARENT or WRAP_CONTENT. */ @ViewDebug.ExportedProperty(mapping = { @ViewDebug.IntToString(from = FILL_PARENT, to = "FILL_PARENT"), @ViewDebug.IntToString(from = WRAP_CONTENT, to = "WRAP_CONTENT") }) public int height; /** * Used to animate layouts. */ public LayoutAnimationController.AnimationParameters layoutAnimationParameters; /** * Creates a new set of layout parameters. The values are extracted from * the supplied attributes set and context. The XML attributes mapped * to this set of layout parameters are: * * <ul> * <li><code>layout_width</code>: the width, either an exact value, * {@link #WRAP_CONTENT} or {@link #FILL_PARENT}</li> * <li><code>layout_height</code>: the height, either an exact value, * {@link #WRAP_CONTENT} or {@link #FILL_PARENT}</li> * </ul> * * @param c the application environment * @param attrs the set of attributes from which to extract the layout * parameters' values */ public LayoutParams(Context c, AttributeSet attrs) { TypedArray a = c.obtainStyledAttributes(attrs, R.styleable.ViewGroup_Layout); setBaseAttributes(a, R.styleable.ViewGroup_Layout_layout_width, R.styleable.ViewGroup_Layout_layout_height); a.recycle(); } /** * Creates a new set of layout parameters with the specified width * and height. * * @param width the width, either {@link #FILL_PARENT}, * {@link #WRAP_CONTENT} or a fixed size in pixels * @param height the height, either {@link #FILL_PARENT}, * {@link #WRAP_CONTENT} or a fixed size in pixels */ public LayoutParams(int width, int height) { this.width = width; this.height = height; } /** * Copy constructor. Clones the width and height values of the source. * * @param source The layout params to copy from. */ public LayoutParams(LayoutParams source) { this.width = source.width; this.height = source.height; } /** * Used internally by MarginLayoutParams. * @hide */ LayoutParams() { } /** * Extracts the layout parameters from the supplied attributes. * * @param a the style attributes to extract the parameters from * @param widthAttr the identifier of the width attribute * @param heightAttr the identifier of the height attribute */ protected void setBaseAttributes(TypedArray a, int widthAttr, int heightAttr) { width = a.getLayoutDimension(widthAttr, "layout_width"); height = a.getLayoutDimension(heightAttr, "layout_height"); } /** * Returns a String representation of this set of layout parameters. * * @param output the String to prepend to the internal representation * @return a String with the following format: output + * "ViewGroup.LayoutParams={ width=WIDTH, height=HEIGHT }" * * @hide */ public String debug(String output) { return output + "ViewGroup.LayoutParams={ width=" + sizeToString(width) + ", height=" + sizeToString(height) + " }"; } /** * Converts the specified size to a readable String. * * @param size the size to convert * @return a String instance representing the supplied size * * @hide */ protected static String sizeToString(int size) { if (size == WRAP_CONTENT) { return "wrap-content"; } if (size == FILL_PARENT) { return "fill-parent"; } return String.valueOf(size); } } /** * Per-child layout information for layouts that support margins. * See * {@link android.R.styleable#ViewGroup_MarginLayout ViewGroup Margin Layout Attributes} * for a list of all child view attributes that this class supports. */ public static class MarginLayoutParams extends ViewGroup.LayoutParams { /** * The left margin in pixels of the child. */ @ViewDebug.ExportedProperty public int leftMargin; /** * The top margin in pixels of the child. */ @ViewDebug.ExportedProperty public int topMargin; /** * The right margin in pixels of the child. */ @ViewDebug.ExportedProperty public int rightMargin; /** * The bottom margin in pixels of the child. */ @ViewDebug.ExportedProperty public int bottomMargin; /** * Creates a new set of layout parameters. The values are extracted from * the supplied attributes set and context. * * @param c the application environment * @param attrs the set of attributes from which to extract the layout * parameters' values */ public MarginLayoutParams(Context c, AttributeSet attrs) { super(); TypedArray a = c.obtainStyledAttributes(attrs, R.styleable.ViewGroup_MarginLayout); setBaseAttributes(a, R.styleable.ViewGroup_MarginLayout_layout_width, R.styleable.ViewGroup_MarginLayout_layout_height); int margin = a.getDimensionPixelSize( com.android.internal.R.styleable.ViewGroup_MarginLayout_layout_margin, -1); if (margin >= 0) { leftMargin = margin; topMargin = margin; rightMargin= margin; bottomMargin = margin; } else { leftMargin = a.getDimensionPixelSize( R.styleable.ViewGroup_MarginLayout_layout_marginLeft, 0); topMargin = a.getDimensionPixelSize( R.styleable.ViewGroup_MarginLayout_layout_marginTop, 0); rightMargin = a.getDimensionPixelSize( R.styleable.ViewGroup_MarginLayout_layout_marginRight, 0); bottomMargin = a.getDimensionPixelSize( R.styleable.ViewGroup_MarginLayout_layout_marginBottom, 0); } a.recycle(); } /** * {@inheritDoc} */ public MarginLayoutParams(int width, int height) { super(width, height); } /** * Copy constructor. Clones the width, height and margin values of the source. * * @param source The layout params to copy from. */ public MarginLayoutParams(MarginLayoutParams source) { this.width = source.width; this.height = source.height; this.leftMargin = source.leftMargin; this.topMargin = source.topMargin; this.rightMargin = source.rightMargin; this.bottomMargin = source.bottomMargin; } /** * {@inheritDoc} */ public MarginLayoutParams(LayoutParams source) { super(source); } /** * Sets the margins, in pixels. * * @param left the left margin size * @param top the top margin size * @param right the right margin size * @param bottom the bottom margin size * * @attr ref android.R.styleable#ViewGroup_MarginLayout_layout_marginLeft * @attr ref android.R.styleable#ViewGroup_MarginLayout_layout_marginTop * @attr ref android.R.styleable#ViewGroup_MarginLayout_layout_marginRight * @attr ref android.R.styleable#ViewGroup_MarginLayout_layout_marginBottom */ public void setMargins(int left, int top, int right, int bottom) { leftMargin = left; topMargin = top; rightMargin = right; bottomMargin = bottom; } } }