From 564a8f697b3f3a287d9a4cce14ac0fe1a046709e Mon Sep 17 00:00:00 2001
From: Filip Gruszczynski <gruszczy@google.com>
Date: Fri, 20 Nov 2015 11:25:23 -0800
Subject: [PATCH] Synchronize thumbnail header in recents to freeform
 animation.

Bug: 24913782
Change-Id: I46792ea3135794e514894783e1ee5fa696576f7f
---
 .../com/android/server/wm/AppWindowAnimator.java   | 29 +++++++++++++++-------
 1 file changed, 20 insertions(+), 9 deletions(-)

diff --git a/services/core/java/com/android/server/wm/AppWindowAnimator.java b/services/core/java/com/android/server/wm/AppWindowAnimator.java
index dfd01efe36d0..b32ec2d1b0a6 100644
--- a/services/core/java/com/android/server/wm/AppWindowAnimator.java
+++ b/services/core/java/com/android/server/wm/AppWindowAnimator.java
@@ -228,7 +228,8 @@ public class AppWindowAnimator {
 
     private void stepThumbnailAnimation(long currentTime) {
         thumbnailTransformation.clear();
-        thumbnailAnimation.getTransformation(currentTime, thumbnailTransformation);
+        final long animationFrameTime = getAnimationFrameTime(thumbnailAnimation, currentTime);
+        thumbnailAnimation.getTransformation(animationFrameTime, thumbnailTransformation);
         thumbnailTransformation.getMatrix().preTranslate(thumbnailX, thumbnailY);
 
         ScreenRotationAnimation screenRotationAnimation =
@@ -265,16 +266,26 @@ public class AppWindowAnimator {
                 tmpFloats[Matrix.MSKEW_X], tmpFloats[Matrix.MSCALE_Y]);
     }
 
+    /**
+     * Sometimes we need to synchronize the first frame of animation with some external event, e.g.
+     * Recents hiding some of its content. To achieve this, we prolong the start of the animaiton
+     * and keep producing the first frame of the animation.
+     */
+    private long getAnimationFrameTime(Animation animation, long currentTime) {
+        if (mProlongAnimation == PROLONG_ANIMATION_AT_START) {
+            animation.setStartTime(currentTime);
+            return currentTime + 1;
+        }
+        return currentTime;
+    }
+
     private boolean stepAnimation(long currentTime) {
         if (animation == null) {
             return false;
         }
         transformation.clear();
-        if (mProlongAnimation == PROLONG_ANIMATION_AT_START) {
-            animation.setStartTime(currentTime);
-            currentTime += 1;
-        }
-        boolean hasMoreFrames = animation.getTransformation(currentTime, transformation);
+        final long animationFrameTime = getAnimationFrameTime(animation, currentTime);
+        boolean hasMoreFrames = animation.getTransformation(animationFrameTime, transformation);
         if (!hasMoreFrames) {
             if (deferThumbnailDestruction && !deferFinalFrameCleanup) {
                 // We are deferring the thumbnail destruction, so extend the animation for one more
@@ -290,10 +301,10 @@ public class AppWindowAnimator {
                     hasMoreFrames = true;
                 } else {
                     animation = null;
+                    clearThumbnail();
+                    if (DEBUG_ANIM) Slog.v(TAG, "Finished animation in " + mAppToken + " @ "
+                            + currentTime);
                 }
-                clearThumbnail();
-                if (DEBUG_ANIM) Slog.v(TAG,
-                        "Finished animation in " + mAppToken + " @ " + currentTime);
             }
         }
         hasTransformation = hasMoreFrames;
-- 
2.11.0