3 files changed, 60 insertions, 1 deletions

diff --git a/core/java/android/app/Activity.java b/core/java/android/app/Activity.java
index 148527f..fab88a2 100644
--- a/core/java/android/app/Activity.java
+++ b/core/java/android/app/Activity.java
@@ -5620,6 +5620,16 @@ public class Activity extends ContextThemeWrapper
     }
 
     /**
+     * @hide
+     */
+    public void dispatchEnterAnimationComplete() {
+        onEnterAnimationComplete();
+        if (getWindow() != null && getWindow().getDecorView() != null) {
+            getWindow().getDecorView().getViewTreeObserver().dispatchOnEnterAnimationComplete();
+        }
+    }
+
+    /**
      * Adjust the current immersive mode setting.
      *
      * Note that changing this value will have no effect on the activity's
diff --git a/core/java/android/app/ActivityThread.java b/core/java/android/app/ActivityThread.java
index 98a096c..b64e724 100644
--- a/core/java/android/app/ActivityThread.java
+++ b/core/java/android/app/ActivityThread.java
@@ -2536,7 +2536,7 @@ public final class ActivityThread {
     private void handleEnterAnimationComplete(IBinder token) {
         ActivityClientRecord r = mActivities.get(token);
         if (r != null) {
-            r.activity.onEnterAnimationComplete();
+            r.activity.dispatchEnterAnimationComplete();
         }
     }
 
diff --git a/core/java/android/view/ViewTreeObserver.java b/core/java/android/view/ViewTreeObserver.java
index b85fec8..521fd31 100644
--- a/core/java/android/view/ViewTreeObserver.java
+++ b/core/java/android/view/ViewTreeObserver.java
@@ -37,6 +37,8 @@ public final class ViewTreeObserver {
     private CopyOnWriteArrayList<OnWindowAttachListener> mOnWindowAttachListeners;
     private CopyOnWriteArrayList<OnGlobalFocusChangeListener> mOnGlobalFocusListeners;
     private CopyOnWriteArrayList<OnTouchModeChangeListener> mOnTouchModeChangeListeners;
+    private CopyOnWriteArrayList<OnEnterAnimationCompleteListener>
+            mOnEnterAnimationCompleteListeners;
 
     // Non-recursive listeners use CopyOnWriteArray
     // Any listener invoked from ViewRootImpl.performTraversals() should not be recursive
@@ -316,6 +318,13 @@ public final class ViewTreeObserver {
     }
 
     /**
+     * @hide
+     */
+    public interface OnEnterAnimationCompleteListener {
+        public void onEnterAnimationComplete();
+    }
+
+    /**
      * Creates a new ViewTreeObserver. This constructor should not be called
      */
     ViewTreeObserver() {
@@ -780,6 +789,29 @@ public final class ViewTreeObserver {
         mOnComputeInternalInsetsListeners.remove(victim);
     }
 
+    /**
+     * @hide
+     */
+    public void addOnEnterAnimationCompleteListener(OnEnterAnimationCompleteListener listener) {
+        checkIsAlive();
+        if (mOnEnterAnimationCompleteListeners == null) {
+            mOnEnterAnimationCompleteListeners =
+                    new CopyOnWriteArrayList<OnEnterAnimationCompleteListener>();
+        }
+        mOnEnterAnimationCompleteListeners.add(listener);
+    }
+
+    /**
+     * @hide
+     */
+    public void removeOnEnterAnimationCompleteListener(OnEnterAnimationCompleteListener listener) {
+        checkIsAlive();
+        if (mOnEnterAnimationCompleteListeners == null) {
+            return;
+        }
+        mOnEnterAnimationCompleteListeners.remove(listener);
+    }
+
     private void checkIsAlive() {
         if (!mAlive) {
             throw new IllegalStateException("This ViewTreeObserver is not alive, call "
@@ -1022,6 +1054,23 @@ public final class ViewTreeObserver {
     }
 
     /**
+     * @hide
+     */
+    public final void dispatchOnEnterAnimationComplete() {
+        // 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<OnEnterAnimationCompleteListener> listeners =
+                mOnEnterAnimationCompleteListeners;
+        if (listeners != null && !listeners.isEmpty()) {
+            for (OnEnterAnimationCompleteListener listener : listeners) {
+                listener.onEnterAnimationComplete();
+            }
+        }
+    }
+
+    /**
      * 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.