Fix animation and layoutTransition issues.

There were some subtle timing issues in animators with ending animations that
were not completely initialized (possibly because a startDelay'd animator
was ended before the delay elapsed).
Also, LayoutTransition had bugs around running a transition on a container
while a previously-started transition was still in progress. This could result
in some minor artifacts or crash bugs, depending on the durations and delays set
on the transition animations.

Change-Id: Ic6a69601f1ce9a55db15fff6b8ed25950b354491

2 files changed, 38 insertions, 13 deletions

diff --git a/core/java/android/animation/LayoutTransition.java b/core/java/android/animation/LayoutTransition.java
index d3e10f3..8b59554 100644
--- a/core/java/android/animation/LayoutTransition.java
+++ b/core/java/android/animation/LayoutTransition.java
@@ -617,7 +617,6 @@ public class LayoutTransition {
                         Animator prevAnimation = currentChangingAnimations.get(child);
                         if (prevAnimation != null) {
                             prevAnimation.cancel();
-                            currentChangingAnimations.remove(child);
                         }
                         Animator pendingAnimation = pendingAnimations.get(child);
                         if (pendingAnimation != null) {
@@ -639,7 +638,6 @@ public class LayoutTransition {
                 };
                 // Remove the animation from the cache when it ends
                 anim.addListener(new AnimatorListenerAdapter() {
-                    private boolean canceled = false;
 
                     @Override
                     public void onAnimationStart(Animator animator) {
@@ -654,17 +652,13 @@ public class LayoutTransition {
 
                     @Override
                     public void onAnimationCancel(Animator animator) {
-                        // we remove canceled animations immediately, not here
-                        canceled = true;
                         child.removeOnLayoutChangeListener(listener);
                         layoutChangeListenerMap.remove(child);
                     }
 
                     @Override
                     public void onAnimationEnd(Animator animator) {
-                        if (!canceled) {
-                            currentChangingAnimations.remove(child);
-                        }
+                        currentChangingAnimations.remove(child);
                         if (mListeners != null) {
                             for (TransitionListener listener : mListeners) {
                                 listener.endTransition(LayoutTransition.this, parent, child,
@@ -719,6 +713,28 @@ public class LayoutTransition {
     }
 
     /**
+     * Cancels the currently running transition. Note that we cancel() the changing animations
+     * but end() the visibility animations. This is because this method is currently called
+     * in the context of starting a new transition, so we want to move things from their mid-
+     * transition positions, but we want them to have their end-transition visibility.
+     *
+     * @hide
+     */
+    public void cancel() {
+        HashMap<View, Animator> currentAnimCopy =
+                (HashMap<View, Animator>) currentChangingAnimations.clone();
+        for (Animator anim : currentAnimCopy.values()) {
+            anim.cancel();
+        }
+        currentChangingAnimations.clear();
+        currentAnimCopy = (HashMap<View, Animator>) currentVisibilityAnimations.clone();
+        for (Animator anim : currentAnimCopy.values()) {
+            anim.end();
+        }
+        currentVisibilityAnimations.clear();
+    }
+
+    /**
      * This method runs the animation that makes an added item appear.
      *
      * @param parent The ViewGroup to which the View is being added.
@@ -810,6 +826,9 @@ public class LayoutTransition {
      * @param child The View being added to the ViewGroup.
      */
     public void addChild(ViewGroup parent, View child) {
+        if (isRunning()) {
+            cancel();
+        }
         if (mListeners != null) {
             for (TransitionListener listener : mListeners) {
                 listener.startTransition(this, parent, child, APPEARING);
@@ -842,6 +861,9 @@ public class LayoutTransition {
      * @param child The View being removed from the ViewGroup.
      */
     public void removeChild(ViewGroup parent, View child) {
+        if (isRunning()) {
+            cancel();
+        }
         if (mListeners != null) {
             for (TransitionListener listener : mListeners) {
                 listener.startTransition(this, parent, child, DISAPPEARING);
diff --git a/core/java/android/animation/ValueAnimator.java b/core/java/android/animation/ValueAnimator.java
index 5705057..5a8a74a 100755
--- a/core/java/android/animation/ValueAnimator.java
+++ b/core/java/android/animation/ValueAnimator.java
@@ -895,7 +895,14 @@ public class ValueAnimator extends Animator {
             throw new AndroidRuntimeException("Animators may only be run on Looper threads");
         }
         mPlayingBackwards = playBackwards;
+        mCurrentIteration = 0;
+        mPlayingState = STOPPED;
+        mStartedDelay = false;
+        sPendingAnimations.get().add(this);
         if (mStartDelay == 0) {
+            // This sets the initial value of the animation, prior to actually starting it running
+            setCurrentPlayTime(getCurrentPlayTime());
+
             if (mListeners != null) {
                 ArrayList<AnimatorListener> tmpListeners =
                         (ArrayList<AnimatorListener>) mListeners.clone();
@@ -904,13 +911,7 @@ public class ValueAnimator extends Animator {
                     tmpListeners.get(i).onAnimationStart(this);
                 }
             }
-            // This sets the initial value of the animation, prior to actually starting it running
-            setCurrentPlayTime(getCurrentPlayTime());
         }
-        mCurrentIteration = 0;
-        mPlayingState = STOPPED;
-        mStartedDelay = false;
-        sPendingAnimations.get().add(this);
         AnimationHandler animationHandler = sAnimationHandler.get();
         if (animationHandler == null) {
             animationHandler = new AnimationHandler();
@@ -947,6 +948,8 @@ public class ValueAnimator extends Animator {
             // Special case if the animation has not yet started; get it ready for ending
             mStartedDelay = false;
             startAnimation();
+        } else if (!mInitialized) {
+            initAnimation();
         }
         // The final value set on the target varies, depending on whether the animation
         // was supposed to repeat an odd number of times