Merge "Use Alpha instead of TransitionAlpha for Activity Transitions." into lmp-dev

core/java/android/app/ActivityTransitionCoordinator.java

@@ -205,6 +205,7 @@ abstract class ActivityTransitionCoordinator extends ResultReceiver {
     private boolean mIsStartingTransition;
     private ArrayList<GhostViewListeners> mGhostViewListeners =
             new ArrayList<GhostViewListeners>();
+    private ArrayMap<View, Float> mOriginalAlphas = new ArrayMap<View, Float>();
 
     public ActivityTransitionCoordinator(Window window,
             ArrayList<String> allSharedElementNames,
@@ -580,6 +581,7 @@ abstract class ActivityTransitionCoordinator extends ResultReceiver {
         mWindow = null;
         mSharedElements.clear();
         mTransitioningViews.clear();
+        mOriginalAlphas.clear();
         mResultReceiver = null;
         mPendingTransition = null;
         mListener = null;
@@ -589,10 +591,27 @@ abstract class ActivityTransitionCoordinator extends ResultReceiver {
         return getWindow().getTransitionBackgroundFadeDuration();
     }
 
-    protected static void setTransitionAlpha(ArrayList<View> views, float alpha) {
+    protected void hideViews(ArrayList<View> views) {
         int count = views.size();
         for (int i = 0; i < count; i++) {
-            views.get(i).setTransitionAlpha(alpha);
+            View view = views.get(i);
+            if (!mOriginalAlphas.containsKey(view)) {
+                mOriginalAlphas.put(view, view.getAlpha());
+            }
+            view.setAlpha(0f);
+            view.setTransitionAlpha(0f);
+        }
+    }
+
+    protected void showViews(ArrayList<View> views) {
+        int count = views.size();
+        for (int i = 0; i < count; i++) {
+            View view = views.get(i);
+            Float alpha = mOriginalAlphas.remove(view);
+            if (alpha != null) {
+                view.setAlpha(alpha);
+                view.setTransitionAlpha(1f);
+            }
         }
     }
 

core/java/android/app/EnterTransitionCoordinator.java

@@ -112,9 +112,9 @@ class EnterTransitionCoordinator extends ActivityTransitionCoordinator {
     protected void viewsReady(ArrayMap<String, View> sharedElements) {
         super.viewsReady(sharedElements);
         mIsReadyForTransition = true;
-        setTransitionAlpha(mSharedElements, 0);
+        hideViews(mSharedElements);
         if (getViewsTransition() != null) {
-            setTransitionAlpha(mTransitioningViews, 0);
+            hideViews(mTransitioningViews);
         }
         if (mIsReturning) {
             sendSharedElementDestination();
@@ -240,7 +240,7 @@ class EnterTransitionCoordinator extends ActivityTransitionCoordinator {
         if (!mIsCanceled) {
             mIsCanceled = true;
             if (getViewsTransition() == null || mIsViewsTransitionStarted) {
-                setTransitionAlpha(mSharedElements, 1);
+                showViews(mSharedElements);
             } else {
                 mTransitioningViews.addAll(mSharedElements);
             }
@@ -300,7 +300,7 @@ class EnterTransitionCoordinator extends ActivityTransitionCoordinator {
         // Now start shared element transition
         ArrayList<View> sharedElementSnapshots = createSnapshots(sharedElementState,
                 mSharedElementNames);
-        setTransitionAlpha(mSharedElements, 1);
+        showViews(mSharedElements);
         scheduleSetSharedElementEnd(sharedElementSnapshots);
         ArrayList<SharedElementOriginalState> originalImageViewState =
                 setSharedElementState(sharedElementState, sharedElementSnapshots);
@@ -411,7 +411,7 @@ class EnterTransitionCoordinator extends ActivityTransitionCoordinator {
                     @Override
                     public void onTransitionStart(Transition transition) {
                         mEnterViewsTransition = transition;
-                        setTransitionAlpha(mTransitioningViews, 1);
+                        showViews(mTransitioningViews);
                         super.onTransitionStart(transition);
                     }
 

core/java/android/app/ExitTransitionCoordinator.java

@@ -126,8 +126,8 @@ class ExitTransitionCoordinator extends ActivityTransitionCoordinator {
     }
 
     public void resetViews() {
-        setTransitionAlpha(mTransitioningViews, 1);
-        setTransitionAlpha(mSharedElements, 1);
+        showViews(mTransitioningViews);
+        showViews(mSharedElements);
         mIsHidden = true;
         if (!mIsReturning && getDecor() != null) {
             getDecor().suppressLayout(false);
@@ -187,7 +187,7 @@ class ExitTransitionCoordinator extends ActivityTransitionCoordinator {
     private void hideSharedElements() {
         moveSharedElementsFromOverlay();
         if (!mIsHidden) {
-            setTransitionAlpha(mSharedElements, 0);
+            hideViews(mSharedElements);
         }
         mSharedElementsHidden = true;
         finishIfNecessary();
@@ -296,7 +296,7 @@ class ExitTransitionCoordinator extends ActivityTransitionCoordinator {
                     transition.removeListener(this);
                     exitTransitionComplete();
                     if (mIsHidden) {
-                        setTransitionAlpha(mTransitioningViews, 1);
+                        showViews(mTransitioningViews);
                     }
                     if (mSharedElementBundle != null) {
                         delayCancel();
@@ -323,7 +323,7 @@ class ExitTransitionCoordinator extends ActivityTransitionCoordinator {
                     transition.removeListener(this);
                     sharedElementTransitionComplete();
                     if (mIsHidden) {
-                        setTransitionAlpha(mSharedElements, 1);
+                        showViews(mSharedElements);
                     }
                 }
             });