| /* |
| * Copyright (C) 2008 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 android.graphics.Rect; |
| import android.graphics.Region; |
| |
| import java.util.ArrayList; |
| import java.util.concurrent.CopyOnWriteArrayList; |
| |
| /** |
| * A view tree observer is used to register listeners that can be notified of global |
| * changes in the view tree. Such global events include, but are not limited to, |
| * layout of the whole tree, beginning of the drawing pass, touch mode change.... |
| * |
| * A ViewTreeObserver should never be instantiated by applications as it is provided |
| * by the views hierarchy. Refer to {@link android.view.View#getViewTreeObserver()} |
| * for more information. |
| */ |
| public final class ViewTreeObserver { |
| // Recursive listeners use CopyOnWriteArrayList |
| private CopyOnWriteArrayList<OnWindowFocusChangeListener> mOnWindowFocusListeners; |
| private CopyOnWriteArrayList<OnWindowAttachListener> mOnWindowAttachListeners; |
| private CopyOnWriteArrayList<OnGlobalFocusChangeListener> mOnGlobalFocusListeners; |
| private CopyOnWriteArrayList<OnTouchModeChangeListener> mOnTouchModeChangeListeners; |
| |
| // Non-recursive listeners use CopyOnWriteArray |
| // Any listener invoked from ViewRootImpl.performTraversals() should not be recursive |
| private CopyOnWriteArray<OnGlobalLayoutListener> mOnGlobalLayoutListeners; |
| private CopyOnWriteArray<OnComputeInternalInsetsListener> mOnComputeInternalInsetsListeners; |
| private CopyOnWriteArray<OnScrollChangedListener> mOnScrollChangedListeners; |
| private CopyOnWriteArray<OnPreDrawListener> mOnPreDrawListeners; |
| |
| // These listeners cannot be mutated during dispatch |
| private ArrayList<OnDrawListener> mOnDrawListeners; |
| |
| private boolean mAlive = true; |
| |
| /** |
| * Interface definition for a callback to be invoked when the view hierarchy is |
| * attached to and detached from its window. |
| */ |
| public interface OnWindowAttachListener { |
| /** |
| * Callback method to be invoked when the view hierarchy is attached to a window |
| */ |
| public void onWindowAttached(); |
| |
| /** |
| * Callback method to be invoked when the view hierarchy is detached from a window |
| */ |
| public void onWindowDetached(); |
| } |
| |
| /** |
| * Interface definition for a callback to be invoked when the view hierarchy's window |
| * focus state changes. |
| */ |
| public interface OnWindowFocusChangeListener { |
| /** |
| * Callback method to be invoked when the window focus changes in the view tree. |
| * |
| * @param hasFocus Set to true if the window is gaining focus, false if it is |
| * losing focus. |
| */ |
| public void onWindowFocusChanged(boolean hasFocus); |
| } |
| |
| /** |
| * Interface definition for a callback to be invoked when the focus state within |
| * the view tree changes. |
| */ |
| public interface OnGlobalFocusChangeListener { |
| /** |
| * Callback method to be invoked when the focus changes in the view tree. When |
| * the view tree transitions from touch mode to non-touch mode, oldFocus is null. |
| * When the view tree transitions from non-touch mode to touch mode, newFocus is |
| * null. When focus changes in non-touch mode (without transition from or to |
| * touch mode) either oldFocus or newFocus can be null. |
| * |
| * @param oldFocus The previously focused view, if any. |
| * @param newFocus The newly focused View, if any. |
| */ |
| public void onGlobalFocusChanged(View oldFocus, View newFocus); |
| } |
| |
| /** |
| * Interface definition for a callback to be invoked when the global layout state |
| * or the visibility of views within the view tree changes. |
| */ |
| public interface OnGlobalLayoutListener { |
| /** |
| * Callback method to be invoked when the global layout state or the visibility of views |
| * within the view tree changes |
| */ |
| public void onGlobalLayout(); |
| } |
| |
| /** |
| * Interface definition for a callback to be invoked when the view tree is about to be drawn. |
| */ |
| public interface OnPreDrawListener { |
| /** |
| * Callback method to be invoked when the view tree is about to be drawn. At this point, all |
| * views in the tree have been measured and given a frame. Clients can use this to adjust |
| * their scroll bounds or even to request a new layout before drawing occurs. |
| * |
| * @return Return true to proceed with the current drawing pass, or false to cancel. |
| * |
| * @see android.view.View#onMeasure |
| * @see android.view.View#onLayout |
| * @see android.view.View#onDraw |
| */ |
| public boolean onPreDraw(); |
| } |
| |
| /** |
| * Interface definition for a callback to be invoked when the view tree is about to be drawn. |
| */ |
| public interface OnDrawListener { |
| /** |
| * <p>Callback method to be invoked when the view tree is about to be drawn. At this point, |
| * views cannot be modified in any way.</p> |
| * |
| * <p>Unlike with {@link OnPreDrawListener}, this method cannot be used to cancel the |
| * current drawing pass.</p> |
| * |
| * <p>An {@link OnDrawListener} listener <strong>cannot be added or removed</strong> |
| * from this method.</p> |
| * |
| * @see android.view.View#onMeasure |
| * @see android.view.View#onLayout |
| * @see android.view.View#onDraw |
| */ |
| public void onDraw(); |
| } |
| |
| /** |
| * Interface definition for a callback to be invoked when the touch mode changes. |
| */ |
| public interface OnTouchModeChangeListener { |
| /** |
| * Callback method to be invoked when the touch mode changes. |
| * |
| * @param isInTouchMode True if the view hierarchy is now in touch mode, false otherwise. |
| */ |
| public void onTouchModeChanged(boolean isInTouchMode); |
| } |
| |
| /** |
| * Interface definition for a callback to be invoked when |
| * something in the view tree has been scrolled. |
| */ |
| public interface OnScrollChangedListener { |
| /** |
| * Callback method to be invoked when something in the view tree |
| * has been scrolled. |
| */ |
| public void onScrollChanged(); |
| } |
| |
| /** |
| * Parameters used with OnComputeInternalInsetsListener. |
| * |
| * We are not yet ready to commit to this API and support it, so |
| * @hide |
| */ |
| public final static class InternalInsetsInfo { |
| /** |
| * Offsets from the frame of the window at which the content of |
| * windows behind it should be placed. |
| */ |
| public final Rect contentInsets = new Rect(); |
| |
| /** |
| * Offsets from the frame of the window at which windows behind it |
| * are visible. |
| */ |
| public final Rect visibleInsets = new Rect(); |
| |
| /** |
| * Touchable region defined relative to the origin of the frame of the window. |
| * Only used when {@link #setTouchableInsets(int)} is called with |
| * the option {@link #TOUCHABLE_INSETS_REGION}. |
| */ |
| public final Region touchableRegion = new Region(); |
| |
| /** |
| * Option for {@link #setTouchableInsets(int)}: the entire window frame |
| * can be touched. |
| */ |
| public static final int TOUCHABLE_INSETS_FRAME = 0; |
| |
| /** |
| * Option for {@link #setTouchableInsets(int)}: the area inside of |
| * the content insets can be touched. |
| */ |
| public static final int TOUCHABLE_INSETS_CONTENT = 1; |
| |
| /** |
| * Option for {@link #setTouchableInsets(int)}: the area inside of |
| * the visible insets can be touched. |
| */ |
| public static final int TOUCHABLE_INSETS_VISIBLE = 2; |
| |
| /** |
| * Option for {@link #setTouchableInsets(int)}: the area inside of |
| * the provided touchable region in {@link #touchableRegion} can be touched. |
| */ |
| public static final int TOUCHABLE_INSETS_REGION = 3; |
| |
| /** |
| * Set which parts of the window can be touched: either |
| * {@link #TOUCHABLE_INSETS_FRAME}, {@link #TOUCHABLE_INSETS_CONTENT}, |
| * {@link #TOUCHABLE_INSETS_VISIBLE}, or {@link #TOUCHABLE_INSETS_REGION}. |
| */ |
| public void setTouchableInsets(int val) { |
| mTouchableInsets = val; |
| } |
| |
| int mTouchableInsets; |
| |
| void reset() { |
| contentInsets.setEmpty(); |
| visibleInsets.setEmpty(); |
| touchableRegion.setEmpty(); |
| mTouchableInsets = TOUCHABLE_INSETS_FRAME; |
| } |
| |
| @Override |
| public int hashCode() { |
| int result = contentInsets.hashCode(); |
| result = 31 * result + visibleInsets.hashCode(); |
| result = 31 * result + touchableRegion.hashCode(); |
| result = 31 * result + mTouchableInsets; |
| return result; |
| } |
| |
| @Override |
| public boolean equals(Object o) { |
| if (this == o) return true; |
| if (o == null || getClass() != o.getClass()) return false; |
| |
| InternalInsetsInfo other = (InternalInsetsInfo)o; |
| return mTouchableInsets == other.mTouchableInsets && |
| contentInsets.equals(other.contentInsets) && |
| visibleInsets.equals(other.visibleInsets) && |
| touchableRegion.equals(other.touchableRegion); |
| } |
| |
| void set(InternalInsetsInfo other) { |
| contentInsets.set(other.contentInsets); |
| visibleInsets.set(other.visibleInsets); |
| touchableRegion.set(other.touchableRegion); |
| mTouchableInsets = other.mTouchableInsets; |
| } |
| } |
| |
| /** |
| * Interface definition for a callback to be invoked when layout has |
| * completed and the client can compute its interior insets. |
| * |
| * We are not yet ready to commit to this API and support it, so |
| * @hide |
| */ |
| public interface OnComputeInternalInsetsListener { |
| /** |
| * Callback method to be invoked when layout has completed and the |
| * client can compute its interior insets. |
| * |
| * @param inoutInfo Should be filled in by the implementation with |
| * the information about the insets of the window. This is called |
| * with whatever values the previous OnComputeInternalInsetsListener |
| * returned, if there are multiple such listeners in the window. |
| */ |
| public void onComputeInternalInsets(InternalInsetsInfo inoutInfo); |
| } |
| |
| /** |
| * Creates a new ViewTreeObserver. This constructor should not be called |
| */ |
| ViewTreeObserver() { |
| } |
| |
| /** |
| * Merges all the listeners registered on the specified observer with the listeners |
| * registered on this object. After this method is invoked, the specified observer |
| * will return false in {@link #isAlive()} and should not be used anymore. |
| * |
| * @param observer The ViewTreeObserver whose listeners must be added to this observer |
| */ |
| void merge(ViewTreeObserver observer) { |
| if (observer.mOnWindowAttachListeners != null) { |
| if (mOnWindowAttachListeners != null) { |
| mOnWindowAttachListeners.addAll(observer.mOnWindowAttachListeners); |
| } else { |
| mOnWindowAttachListeners = observer.mOnWindowAttachListeners; |
| } |
| } |
| |
| if (observer.mOnWindowFocusListeners != null) { |
| if (mOnWindowFocusListeners != null) { |
| mOnWindowFocusListeners.addAll(observer.mOnWindowFocusListeners); |
| } else { |
| mOnWindowFocusListeners = observer.mOnWindowFocusListeners; |
| } |
| } |
| |
| if (observer.mOnGlobalFocusListeners != null) { |
| if (mOnGlobalFocusListeners != null) { |
| mOnGlobalFocusListeners.addAll(observer.mOnGlobalFocusListeners); |
| } else { |
| mOnGlobalFocusListeners = observer.mOnGlobalFocusListeners; |
| } |
| } |
| |
| if (observer.mOnGlobalLayoutListeners != null) { |
| if (mOnGlobalLayoutListeners != null) { |
| mOnGlobalLayoutListeners.addAll(observer.mOnGlobalLayoutListeners); |
| } else { |
| mOnGlobalLayoutListeners = observer.mOnGlobalLayoutListeners; |
| } |
| } |
| |
| if (observer.mOnPreDrawListeners != null) { |
| if (mOnPreDrawListeners != null) { |
| mOnPreDrawListeners.addAll(observer.mOnPreDrawListeners); |
| } else { |
| mOnPreDrawListeners = observer.mOnPreDrawListeners; |
| } |
| } |
| |
| if (observer.mOnTouchModeChangeListeners != null) { |
| if (mOnTouchModeChangeListeners != null) { |
| mOnTouchModeChangeListeners.addAll(observer.mOnTouchModeChangeListeners); |
| } else { |
| mOnTouchModeChangeListeners = observer.mOnTouchModeChangeListeners; |
| } |
| } |
| |
| if (observer.mOnComputeInternalInsetsListeners != null) { |
| if (mOnComputeInternalInsetsListeners != null) { |
| mOnComputeInternalInsetsListeners.addAll(observer.mOnComputeInternalInsetsListeners); |
| } else { |
| mOnComputeInternalInsetsListeners = observer.mOnComputeInternalInsetsListeners; |
| } |
| } |
| |
| if (observer.mOnScrollChangedListeners != null) { |
| if (mOnScrollChangedListeners != null) { |
| mOnScrollChangedListeners.addAll(observer.mOnScrollChangedListeners); |
| } else { |
| mOnScrollChangedListeners = observer.mOnScrollChangedListeners; |
| } |
| } |
| |
| observer.kill(); |
| } |
| |
| /** |
| * Register a callback to be invoked when the view hierarchy is attached to a window. |
| * |
| * @param listener The callback to add |
| * |
| * @throws IllegalStateException If {@link #isAlive()} returns false |
| */ |
| public void addOnWindowAttachListener(OnWindowAttachListener listener) { |
| checkIsAlive(); |
| |
| if (mOnWindowAttachListeners == null) { |
| mOnWindowAttachListeners |
| = new CopyOnWriteArrayList<OnWindowAttachListener>(); |
| } |
| |
| mOnWindowAttachListeners.add(listener); |
| } |
| |
| /** |
| * Remove a previously installed window attach callback. |
| * |
| * @param victim The callback to remove |
| * |
| * @throws IllegalStateException If {@link #isAlive()} returns false |
| * |
| * @see #addOnWindowAttachListener(android.view.ViewTreeObserver.OnWindowAttachListener) |
| */ |
| public void removeOnWindowAttachListener(OnWindowAttachListener victim) { |
| checkIsAlive(); |
| if (mOnWindowAttachListeners == null) { |
| return; |
| } |
| mOnWindowAttachListeners.remove(victim); |
| } |
| |
| /** |
| * Register a callback to be invoked when the window focus state within the view tree changes. |
| * |
| * @param listener The callback to add |
| * |
| * @throws IllegalStateException If {@link #isAlive()} returns false |
| */ |
| public void addOnWindowFocusChangeListener(OnWindowFocusChangeListener listener) { |
| checkIsAlive(); |
| |
| if (mOnWindowFocusListeners == null) { |
| mOnWindowFocusListeners |
| = new CopyOnWriteArrayList<OnWindowFocusChangeListener>(); |
| } |
| |
| mOnWindowFocusListeners.add(listener); |
| } |
| |
| /** |
| * Remove a previously installed window focus change callback. |
| * |
| * @param victim The callback to remove |
| * |
| * @throws IllegalStateException If {@link #isAlive()} returns false |
| * |
| * @see #addOnWindowFocusChangeListener(android.view.ViewTreeObserver.OnWindowFocusChangeListener) |
| */ |
| public void removeOnWindowFocusChangeListener(OnWindowFocusChangeListener victim) { |
| checkIsAlive(); |
| if (mOnWindowFocusListeners == null) { |
| return; |
| } |
| mOnWindowFocusListeners.remove(victim); |
| } |
| |
| /** |
| * Register a callback to be invoked when the focus state within the view tree changes. |
| * |
| * @param listener The callback to add |
| * |
| * @throws IllegalStateException If {@link #isAlive()} returns false |
| */ |
| public void addOnGlobalFocusChangeListener(OnGlobalFocusChangeListener listener) { |
| checkIsAlive(); |
| |
| if (mOnGlobalFocusListeners == null) { |
| mOnGlobalFocusListeners = new CopyOnWriteArrayList<OnGlobalFocusChangeListener>(); |
| } |
| |
| mOnGlobalFocusListeners.add(listener); |
| } |
| |
| /** |
| * Remove a previously installed focus change callback. |
| * |
| * @param victim The callback to remove |
| * |
| * @throws IllegalStateException If {@link #isAlive()} returns false |
| * |
| * @see #addOnGlobalFocusChangeListener(OnGlobalFocusChangeListener) |
| */ |
| public void removeOnGlobalFocusChangeListener(OnGlobalFocusChangeListener victim) { |
| checkIsAlive(); |
| if (mOnGlobalFocusListeners == null) { |
| return; |
| } |
| mOnGlobalFocusListeners.remove(victim); |
| } |
| |
| /** |
| * Register a callback to be invoked when the global layout state or the visibility of views |
| * within the view tree changes |
| * |
| * @param listener The callback to add |
| * |
| * @throws IllegalStateException If {@link #isAlive()} returns false |
| */ |
| public void addOnGlobalLayoutListener(OnGlobalLayoutListener listener) { |
| checkIsAlive(); |
| |
| if (mOnGlobalLayoutListeners == null) { |
| mOnGlobalLayoutListeners = new CopyOnWriteArray<OnGlobalLayoutListener>(); |
| } |
| |
| mOnGlobalLayoutListeners.add(listener); |
| } |
| |
| /** |
| * Remove a previously installed global layout callback |
| * |
| * @param victim The callback to remove |
| * |
| * @throws IllegalStateException If {@link #isAlive()} returns false |
| * |
| * @deprecated Use #removeOnGlobalLayoutListener instead |
| * |
| * @see #addOnGlobalLayoutListener(OnGlobalLayoutListener) |
| */ |
| @Deprecated |
| public void removeGlobalOnLayoutListener(OnGlobalLayoutListener victim) { |
| removeOnGlobalLayoutListener(victim); |
| } |
| |
| /** |
| * Remove a previously installed global layout callback |
| * |
| * @param victim The callback to remove |
| * |
| * @throws IllegalStateException If {@link #isAlive()} returns false |
| * |
| * @see #addOnGlobalLayoutListener(OnGlobalLayoutListener) |
| */ |
| public void removeOnGlobalLayoutListener(OnGlobalLayoutListener victim) { |
| checkIsAlive(); |
| if (mOnGlobalLayoutListeners == null) { |
| return; |
| } |
| mOnGlobalLayoutListeners.remove(victim); |
| } |
| |
| /** |
| * Register a callback to be invoked when the view tree is about to be drawn |
| * |
| * @param listener The callback to add |
| * |
| * @throws IllegalStateException If {@link #isAlive()} returns false |
| */ |
| public void addOnPreDrawListener(OnPreDrawListener listener) { |
| checkIsAlive(); |
| |
| if (mOnPreDrawListeners == null) { |
| mOnPreDrawListeners = new CopyOnWriteArray<OnPreDrawListener>(); |
| } |
| |
| mOnPreDrawListeners.add(listener); |
| } |
| |
| /** |
| * Remove a previously installed pre-draw callback |
| * |
| * @param victim The callback to remove |
| * |
| * @throws IllegalStateException If {@link #isAlive()} returns false |
| * |
| * @see #addOnPreDrawListener(OnPreDrawListener) |
| */ |
| public void removeOnPreDrawListener(OnPreDrawListener victim) { |
| checkIsAlive(); |
| if (mOnPreDrawListeners == null) { |
| return; |
| } |
| mOnPreDrawListeners.remove(victim); |
| } |
| |
| /** |
| * <p>Register a callback to be invoked when the view tree is about to be drawn.</p> |
| * <p><strong>Note:</strong> this method <strong>cannot</strong> be invoked from |
| * {@link android.view.ViewTreeObserver.OnDrawListener#onDraw()}.</p> |
| * |
| * @param listener The callback to add |
| * |
| * @throws IllegalStateException If {@link #isAlive()} returns false |
| */ |
| public void addOnDrawListener(OnDrawListener listener) { |
| checkIsAlive(); |
| |
| if (mOnDrawListeners == null) { |
| mOnDrawListeners = new ArrayList<OnDrawListener>(); |
| } |
| |
| mOnDrawListeners.add(listener); |
| } |
| |
| /** |
| * <p>Remove a previously installed pre-draw callback.</p> |
| * <p><strong>Note:</strong> this method <strong>cannot</strong> be invoked from |
| * {@link android.view.ViewTreeObserver.OnDrawListener#onDraw()}.</p> |
| * |
| * @param victim The callback to remove |
| * |
| * @throws IllegalStateException If {@link #isAlive()} returns false |
| * |
| * @see #addOnDrawListener(OnDrawListener) |
| */ |
| public void removeOnDrawListener(OnDrawListener victim) { |
| checkIsAlive(); |
| if (mOnDrawListeners == null) { |
| return; |
| } |
| mOnDrawListeners.remove(victim); |
| } |
| |
| /** |
| * Register a callback to be invoked when a view has been scrolled. |
| * |
| * @param listener The callback to add |
| * |
| * @throws IllegalStateException If {@link #isAlive()} returns false |
| */ |
| public void addOnScrollChangedListener(OnScrollChangedListener listener) { |
| checkIsAlive(); |
| |
| if (mOnScrollChangedListeners == null) { |
| mOnScrollChangedListeners = new CopyOnWriteArray<OnScrollChangedListener>(); |
| } |
| |
| mOnScrollChangedListeners.add(listener); |
| } |
| |
| /** |
| * Remove a previously installed scroll-changed callback |
| * |
| * @param victim The callback to remove |
| * |
| * @throws IllegalStateException If {@link #isAlive()} returns false |
| * |
| * @see #addOnScrollChangedListener(OnScrollChangedListener) |
| */ |
| public void removeOnScrollChangedListener(OnScrollChangedListener victim) { |
| checkIsAlive(); |
| if (mOnScrollChangedListeners == null) { |
| return; |
| } |
| mOnScrollChangedListeners.remove(victim); |
| } |
| |
| /** |
| * Register a callback to be invoked when the invoked when the touch mode changes. |
| * |
| * @param listener The callback to add |
| * |
| * @throws IllegalStateException If {@link #isAlive()} returns false |
| */ |
| public void addOnTouchModeChangeListener(OnTouchModeChangeListener listener) { |
| checkIsAlive(); |
| |
| if (mOnTouchModeChangeListeners == null) { |
| mOnTouchModeChangeListeners = new CopyOnWriteArrayList<OnTouchModeChangeListener>(); |
| } |
| |
| mOnTouchModeChangeListeners.add(listener); |
| } |
| |
| /** |
| * Remove a previously installed touch mode change callback |
| * |
| * @param victim The callback to remove |
| * |
| * @throws IllegalStateException If {@link #isAlive()} returns false |
| * |
| * @see #addOnTouchModeChangeListener(OnTouchModeChangeListener) |
| */ |
| public void removeOnTouchModeChangeListener(OnTouchModeChangeListener victim) { |
| checkIsAlive(); |
| if (mOnTouchModeChangeListeners == null) { |
| return; |
| } |
| mOnTouchModeChangeListeners.remove(victim); |
| } |
| |
| /** |
| * Register a callback to be invoked when the invoked when it is time to |
| * compute the window's internal insets. |
| * |
| * @param listener The callback to add |
| * |
| * @throws IllegalStateException If {@link #isAlive()} returns false |
| * |
| * We are not yet ready to commit to this API and support it, so |
| * @hide |
| */ |
| public void addOnComputeInternalInsetsListener(OnComputeInternalInsetsListener listener) { |
| checkIsAlive(); |
| |
| if (mOnComputeInternalInsetsListeners == null) { |
| mOnComputeInternalInsetsListeners = |
| new CopyOnWriteArray<OnComputeInternalInsetsListener>(); |
| } |
| |
| mOnComputeInternalInsetsListeners.add(listener); |
| } |
| |
| /** |
| * Remove a previously installed internal insets computation callback |
| * |
| * @param victim The callback to remove |
| * |
| * @throws IllegalStateException If {@link #isAlive()} returns false |
| * |
| * @see #addOnComputeInternalInsetsListener(OnComputeInternalInsetsListener) |
| * |
| * We are not yet ready to commit to this API and support it, so |
| * @hide |
| */ |
| public void removeOnComputeInternalInsetsListener(OnComputeInternalInsetsListener victim) { |
| checkIsAlive(); |
| if (mOnComputeInternalInsetsListeners == null) { |
| return; |
| } |
| mOnComputeInternalInsetsListeners.remove(victim); |
| } |
| |
| private void checkIsAlive() { |
| if (!mAlive) { |
| throw new IllegalStateException("This ViewTreeObserver is not alive, call " |
| + "getViewTreeObserver() again"); |
| } |
| } |
| |
| /** |
| * Indicates whether this ViewTreeObserver is alive. When an observer is not alive, |
| * any call to a method (except this one) will throw an exception. |
| * |
| * If an application keeps a long-lived reference to this ViewTreeObserver, it should |
| * always check for the result of this method before calling any other method. |
| * |
| * @return True if this object is alive and be used, false otherwise. |
| */ |
| public boolean isAlive() { |
| return mAlive; |
| } |
| |
| /** |
| * Marks this ViewTreeObserver as not alive. After invoking this method, invoking |
| * any other method but {@link #isAlive()} and {@link #kill()} will throw an Exception. |
| * |
| * @hide |
| */ |
| private void kill() { |
| mAlive = false; |
| } |
| |
| /** |
| * Notifies registered listeners that window has been attached/detached. |
| */ |
| final void dispatchOnWindowAttachedChange(boolean attached) { |
| // NOTE: because of the use of CopyOnWriteArrayList, we *must* use an iterator to |
| // perform the dispatching. The iterator is a safe guard against listeners that |
| // could mutate the list by calling the various add/remove methods. This prevents |
| // the array from being modified while we iterate it. |
| final CopyOnWriteArrayList<OnWindowAttachListener> listeners |
| = mOnWindowAttachListeners; |
| if (listeners != null && listeners.size() > 0) { |
| for (OnWindowAttachListener listener : listeners) { |
| if (attached) listener.onWindowAttached(); |
| else listener.onWindowDetached(); |
| } |
| } |
| } |
| |
| /** |
| * Notifies registered listeners that window focus has changed. |
| */ |
| final void dispatchOnWindowFocusChange(boolean hasFocus) { |
| // NOTE: because of the use of CopyOnWriteArrayList, we *must* use an iterator to |
| // perform the dispatching. The iterator is a safe guard against listeners that |
| // could mutate the list by calling the various add/remove methods. This prevents |
| // the array from being modified while we iterate it. |
| final CopyOnWriteArrayList<OnWindowFocusChangeListener> listeners |
| = mOnWindowFocusListeners; |
| if (listeners != null && listeners.size() > 0) { |
| for (OnWindowFocusChangeListener listener : listeners) { |
| listener.onWindowFocusChanged(hasFocus); |
| } |
| } |
| } |
| |
| /** |
| * Notifies registered listeners that focus has changed. |
| */ |
| final void dispatchOnGlobalFocusChange(View oldFocus, View newFocus) { |
| // NOTE: because of the use of CopyOnWriteArrayList, we *must* use an iterator to |
| // perform the dispatching. The iterator is a safe guard against listeners that |
| // could mutate the list by calling the various add/remove methods. This prevents |
| // the array from being modified while we iterate it. |
| final CopyOnWriteArrayList<OnGlobalFocusChangeListener> listeners = mOnGlobalFocusListeners; |
| if (listeners != null && listeners.size() > 0) { |
| for (OnGlobalFocusChangeListener listener : listeners) { |
| listener.onGlobalFocusChanged(oldFocus, newFocus); |
| } |
| } |
| } |
| |
| /** |
| * Notifies registered listeners that a global layout happened. This can be called |
| * manually if you are forcing a layout on a View or a hierarchy of Views that are |
| * not attached to a Window or in the GONE state. |
| */ |
| public final void dispatchOnGlobalLayout() { |
| // NOTE: because of the use of CopyOnWriteArrayList, we *must* use an iterator to |
| // perform the dispatching. The iterator is a safe guard against listeners that |
| // could mutate the list by calling the various add/remove methods. This prevents |
| // the array from being modified while we iterate it. |
| final CopyOnWriteArray<OnGlobalLayoutListener> listeners = mOnGlobalLayoutListeners; |
| if (listeners != null && listeners.size() > 0) { |
| CopyOnWriteArray.Access<OnGlobalLayoutListener> access = listeners.start(); |
| try { |
| int count = access.size(); |
| for (int i = 0; i < count; i++) { |
| access.get(i).onGlobalLayout(); |
| } |
| } finally { |
| listeners.end(); |
| } |
| } |
| } |
| |
| /** |
| * Returns whether there are listeners for on pre-draw events. |
| */ |
| final boolean hasOnPreDrawListeners() { |
| return mOnPreDrawListeners != null && mOnPreDrawListeners.size() > 0; |
| } |
| |
| /** |
| * Notifies registered listeners that the drawing pass is about to start. If a |
| * listener returns true, then the drawing pass is canceled and rescheduled. This can |
| * be called manually if you are forcing the drawing on a View or a hierarchy of Views |
| * that are not attached to a Window or in the GONE state. |
| * |
| * @return True if the current draw should be canceled and resceduled, false otherwise. |
| */ |
| @SuppressWarnings("unchecked") |
| public final boolean dispatchOnPreDraw() { |
| boolean cancelDraw = false; |
| final CopyOnWriteArray<OnPreDrawListener> listeners = mOnPreDrawListeners; |
| if (listeners != null && listeners.size() > 0) { |
| CopyOnWriteArray.Access<OnPreDrawListener> access = listeners.start(); |
| try { |
| int count = access.size(); |
| for (int i = 0; i < count; i++) { |
| cancelDraw |= !(access.get(i).onPreDraw()); |
| } |
| } finally { |
| listeners.end(); |
| } |
| } |
| return cancelDraw; |
| } |
| |
| /** |
| * Notifies registered listeners that the drawing pass is about to start. |
| */ |
| public final void dispatchOnDraw() { |
| if (mOnDrawListeners != null) { |
| final ArrayList<OnDrawListener> listeners = mOnDrawListeners; |
| int numListeners = listeners.size(); |
| for (int i = 0; i < numListeners; ++i) { |
| listeners.get(i).onDraw(); |
| } |
| } |
| } |
| |
| /** |
| * Notifies registered listeners that the touch mode has changed. |
| * |
| * @param inTouchMode True if the touch mode is now enabled, false otherwise. |
| */ |
| final void dispatchOnTouchModeChanged(boolean inTouchMode) { |
| final CopyOnWriteArrayList<OnTouchModeChangeListener> listeners = |
| mOnTouchModeChangeListeners; |
| if (listeners != null && listeners.size() > 0) { |
| for (OnTouchModeChangeListener listener : listeners) { |
| listener.onTouchModeChanged(inTouchMode); |
| } |
| } |
| } |
| |
| /** |
| * Notifies registered listeners that something has scrolled. |
| */ |
| final void dispatchOnScrollChanged() { |
| // NOTE: because of the use of CopyOnWriteArrayList, we *must* use an iterator to |
| // perform the dispatching. The iterator is a safe guard against listeners that |
| // could mutate the list by calling the various add/remove methods. This prevents |
| // the array from being modified while we iterate it. |
| final CopyOnWriteArray<OnScrollChangedListener> listeners = mOnScrollChangedListeners; |
| if (listeners != null && listeners.size() > 0) { |
| CopyOnWriteArray.Access<OnScrollChangedListener> access = listeners.start(); |
| try { |
| int count = access.size(); |
| for (int i = 0; i < count; i++) { |
| access.get(i).onScrollChanged(); |
| } |
| } finally { |
| listeners.end(); |
| } |
| } |
| } |
| |
| /** |
| * Returns whether there are listeners for computing internal insets. |
| */ |
| final boolean hasComputeInternalInsetsListeners() { |
| final CopyOnWriteArray<OnComputeInternalInsetsListener> listeners = |
| mOnComputeInternalInsetsListeners; |
| return (listeners != null && listeners.size() > 0); |
| } |
| |
| /** |
| * Calls all listeners to compute the current insets. |
| */ |
| final void dispatchOnComputeInternalInsets(InternalInsetsInfo inoutInfo) { |
| // NOTE: because of the use of CopyOnWriteArrayList, we *must* use an iterator to |
| // perform the dispatching. The iterator is a safe guard against listeners that |
| // could mutate the list by calling the various add/remove methods. This prevents |
| // the array from being modified while we iterate it. |
| final CopyOnWriteArray<OnComputeInternalInsetsListener> listeners = |
| mOnComputeInternalInsetsListeners; |
| if (listeners != null && listeners.size() > 0) { |
| CopyOnWriteArray.Access<OnComputeInternalInsetsListener> access = listeners.start(); |
| try { |
| int count = access.size(); |
| for (int i = 0; i < count; i++) { |
| access.get(i).onComputeInternalInsets(inoutInfo); |
| } |
| } finally { |
| listeners.end(); |
| } |
| } |
| } |
| |
| /** |
| * Copy on write array. This array is not thread safe, and only one loop can |
| * iterate over this array at any given time. This class avoids allocations |
| * until a concurrent modification happens. |
| * |
| * Usage: |
| * |
| * CopyOnWriteArray.Access<MyData> access = array.start(); |
| * try { |
| * for (int i = 0; i < access.size(); i++) { |
| * MyData d = access.get(i); |
| * } |
| * } finally { |
| * access.end(); |
| * } |
| */ |
| static class CopyOnWriteArray<T> { |
| private ArrayList<T> mData = new ArrayList<T>(); |
| private ArrayList<T> mDataCopy; |
| |
| private final Access<T> mAccess = new Access<T>(); |
| |
| private boolean mStart; |
| |
| static class Access<T> { |
| private ArrayList<T> mData; |
| private int mSize; |
| |
| T get(int index) { |
| return mData.get(index); |
| } |
| |
| int size() { |
| return mSize; |
| } |
| } |
| |
| CopyOnWriteArray() { |
| } |
| |
| private ArrayList<T> getArray() { |
| if (mStart) { |
| if (mDataCopy == null) mDataCopy = new ArrayList<T>(mData); |
| return mDataCopy; |
| } |
| return mData; |
| } |
| |
| Access<T> start() { |
| if (mStart) throw new IllegalStateException("Iteration already started"); |
| mStart = true; |
| mDataCopy = null; |
| mAccess.mData = mData; |
| mAccess.mSize = mData.size(); |
| return mAccess; |
| } |
| |
| void end() { |
| if (!mStart) throw new IllegalStateException("Iteration not started"); |
| mStart = false; |
| if (mDataCopy != null) { |
| mData = mDataCopy; |
| } |
| mDataCopy = null; |
| mAccess.mData.clear(); |
| mAccess.mSize = 0; |
| } |
| |
| int size() { |
| return getArray().size(); |
| } |
| |
| void add(T item) { |
| getArray().add(item); |
| } |
| |
| void addAll(CopyOnWriteArray<T> array) { |
| getArray().addAll(array.mData); |
| } |
| |
| void remove(T item) { |
| getArray().remove(item); |
| } |
| |
| void clear() { |
| getArray().clear(); |
| } |
| } |
| } |