Allow Activities to opt into using Overlay for shared elements.

Bug 17001227

Change-Id: Icc49a81357ee69abd2a15a1d1efcead298ab3fb7

6 files changed, 62 insertions, 7 deletions

diff --git a/api/current.txt b/api/current.txt
index fc5a3a06f1fe..aac7fcd393be 100644
--- a/api/current.txt
+++ b/api/current.txt
@@ -1445,6 +1445,7 @@ package android {
     field public static final int windowSharedElementExitTransition = 16843834; // 0x101043a
     field public static final int windowSharedElementReenterTransition = 16843954; // 0x10104b2
     field public static final int windowSharedElementReturnTransition = 16843953; // 0x10104b1
+    field public static final int windowSharedElementsUseOverlay = 16843964; // 0x10104bc
     field public static final int windowShowAnimation = 16842934; // 0x10100b6
     field public static final int windowShowWallpaper = 16843410; // 0x1010292
     field public static final int windowSoftInputMode = 16843307; // 0x101022b
@@ -35138,6 +35139,7 @@ package android.view {
     method public android.transition.Transition getSharedElementExitTransition();
     method public android.transition.Transition getSharedElementReenterTransition();
     method public android.transition.Transition getSharedElementReturnTransition();
+    method public boolean getSharedElementsUseOverlay();
     method public abstract int getStatusBarColor();
     method public long getTransitionBackgroundFadeDuration();
     method public android.transition.TransitionManager getTransitionManager();
@@ -35199,6 +35201,7 @@ package android.view {
     method public void setSharedElementExitTransition(android.transition.Transition);
     method public void setSharedElementReenterTransition(android.transition.Transition);
     method public void setSharedElementReturnTransition(android.transition.Transition);
+    method public void setSharedElementsUseOverlay(boolean);
     method public void setSoftInputMode(int);
     method public abstract void setStatusBarColor(int);
     method public abstract void setTitle(java.lang.CharSequence);
diff --git a/core/java/android/app/ActivityTransitionCoordinator.java b/core/java/android/app/ActivityTransitionCoordinator.java
index 7d2f677dbcc8..e4f2b8819982 100644
--- a/core/java/android/app/ActivityTransitionCoordinator.java
+++ b/core/java/android/app/ActivityTransitionCoordinator.java
@@ -665,6 +665,9 @@ abstract class ActivityTransitionCoordinator extends ResultReceiver {
     }
 
     protected void moveSharedElementsToOverlay() {
+        if (!mWindow.getSharedElementsUseOverlay()) {
+            return;
+        }
         int numSharedElements = mSharedElements.size();
         ViewGroup decor = getDecor();
         if (decor != null) {
@@ -700,6 +703,17 @@ abstract class ActivityTransitionCoordinator extends ResultReceiver {
     }
 
     protected void moveSharedElementsFromOverlay() {
+        int numListeners = mGhostViewListeners.size();
+        for (int i = 0; i < numListeners; i++) {
+            GhostViewListeners listener = mGhostViewListeners.get(i);
+            ViewGroup parent = (ViewGroup) listener.getView().getParent();
+            parent.getViewTreeObserver().removeOnPreDrawListener(listener);
+        }
+        mGhostViewListeners.clear();
+
+        if (mWindow == null || !mWindow.getSharedElementsUseOverlay()) {
+            return;
+        }
         ViewGroup decor = getDecor();
         if (decor != null) {
             ViewGroupOverlay overlay = decor.getOverlay();
@@ -709,13 +723,6 @@ abstract class ActivityTransitionCoordinator extends ResultReceiver {
                 GhostView.removeGhost(sharedElement);
             }
         }
-        int numListeners = mGhostViewListeners.size();
-        for (int i = 0; i < numListeners; i++) {
-            GhostViewListeners listener = mGhostViewListeners.get(i);
-            ViewGroup parent = (ViewGroup) listener.getView().getParent();
-            parent.getViewTreeObserver().removeOnPreDrawListener(listener);
-        }
-        mGhostViewListeners.clear();
     }
 
     protected void setGhostVisibility(int visibility) {
diff --git a/core/java/android/view/Window.java b/core/java/android/view/Window.java
index e7b3152f7635..2c7ea3e58a97 100644
--- a/core/java/android/view/Window.java
+++ b/core/java/android/view/Window.java
@@ -1662,6 +1662,27 @@ public abstract class Window {
     public void setTransitionBackgroundFadeDuration(long fadeDurationMillis) { }
 
     /**
+     * Returns <code>true</code> when shared elements should use an Overlay during
+     * shared element transitions or <code>false</code> when they should animate as
+     * part of the normal View hierarchy. The default value is true.
+     *
+     * @return <code>true</code> when shared elements should use an Overlay during
+     * shared element transitions or <code>false</code> when they should animate as
+     * part of the normal View hierarchy.
+     */
+    public boolean getSharedElementsUseOverlay() { return true; }
+
+    /**
+     * Sets whether or not shared elements should use an Overlay during shared element transitions.
+     * The default value is true.
+     *
+     * @param sharedElementsUseOverlay <code>true</code> indicates that shared elements should
+     *                                 be transitioned with an Overlay or <code>false</code>
+     *                                 to transition within the normal View hierarchy.
+     */
+    public void setSharedElementsUseOverlay(boolean sharedElementsUseOverlay) { }
+
+    /**
      * @return the color of the status bar.
      */
     public abstract int getStatusBarColor();
diff --git a/core/res/res/values/attrs.xml b/core/res/res/values/attrs.xml
index ed9e83f2dcc3..27b770141da9 100644
--- a/core/res/res/values/attrs.xml
+++ b/core/res/res/values/attrs.xml
@@ -517,6 +517,10 @@
              {@link android.view.Window#setAllowExitTransitionOverlap(boolean)}. -->
         <attr name="windowAllowExitTransitionOverlap" format="boolean"/>
 
+        <!-- Indicates whether or not shared elements should use an overlay
+             during transitions. The default value is true. -->
+        <attr name="windowSharedElementsUseOverlay" format="boolean"/>
+
         <!-- Internal layout used internally for window decor -->
         <attr name="windowActionBarFullscreenDecorLayout" format="reference" />
 
@@ -1836,6 +1840,10 @@
              {@link android.view.Window#setAllowExitTransitionOverlap(boolean)}. -->
         <attr name="windowAllowExitTransitionOverlap"/>
 
+        <!-- Indicates whether or not shared elements should use an overlay
+             during transitions. The default value is true. -->
+        <attr name="windowSharedElementsUseOverlay"/>
+
         <!-- Flag indicating whether this Window is responsible for drawing the background for the
              system bars. If true and the window is not floating, the system bars are drawn with a
              transparent background and the corresponding areas in this window are filled with the
diff --git a/core/res/res/values/public.xml b/core/res/res/values/public.xml
index 4f0c5eb92ad0..b3b5ca955136 100644
--- a/core/res/res/values/public.xml
+++ b/core/res/res/values/public.xml
@@ -2275,6 +2275,7 @@
   <public type="attr" name="outlineProvider" />
   <public type="attr" name="ageHint" />
   <public type="attr" name="country" />
+  <public type="attr" name="windowSharedElementsUseOverlay" />
 
   <public-padding type="dimen" name="l_resource_pad" end="0x01050010" />
 
diff --git a/policy/src/com/android/internal/policy/impl/PhoneWindow.java b/policy/src/com/android/internal/policy/impl/PhoneWindow.java
index 73358c8166fd..9652ebd7df4a 100644
--- a/policy/src/com/android/internal/policy/impl/PhoneWindow.java
+++ b/policy/src/com/android/internal/policy/impl/PhoneWindow.java
@@ -267,6 +267,7 @@ public class PhoneWindow extends Window implements MenuBuilder.Callback {
     private Boolean mAllowExitTransitionOverlap;
     private Boolean mAllowEnterTransitionOverlap;
     private long mBackgroundFadeDurationMillis = -1;
+    private Boolean mSharedElementsUseOverlay;
 
     static class WindowManagerHolder {
         static final IWindowManager sWindowManager = IWindowManager.Stub.asInterface(
@@ -3546,6 +3547,10 @@ public class PhoneWindow extends Window implements MenuBuilder.Callback {
                             R.styleable.Window_windowTransitionBackgroundFadeDuration,
                             DEFAULT_BACKGROUND_FADE_DURATION_MS);
                 }
+                if (mSharedElementsUseOverlay == null) {
+                    mSharedElementsUseOverlay = getWindowStyle().getBoolean(
+                            R.styleable.Window_windowSharedElementsUseOverlay, true);
+                }
             }
         }
     }
@@ -4024,6 +4029,16 @@ public class PhoneWindow extends Window implements MenuBuilder.Callback {
         mBackgroundFadeDurationMillis = fadeDurationMillis;
     }
 
+    @Override
+    public void setSharedElementsUseOverlay(boolean sharedElementsUseOverlay) {
+        mSharedElementsUseOverlay = sharedElementsUseOverlay;
+    }
+
+    @Override
+    public boolean getSharedElementsUseOverlay() {
+        return (mSharedElementsUseOverlay == null) ? true : mSharedElementsUseOverlay;
+    }
+
     private static final class DrawableFeatureState {
         DrawableFeatureState(int _featureId) {
             featureId = _featureId;