1 files changed, 16 insertions, 1 deletions
diff --git a/core/java/android/view/ViewRootImpl.java b/core/java/android/view/ViewRootImpl.java
index 239185e5c25d..7c814f4a5773 100644
--- a/core/java/android/view/ViewRootImpl.java
+++ b/core/java/android/view/ViewRootImpl.java
@@ -80,6 +80,7 @@ import android.util.SparseBooleanArray;
 import android.util.TimeUtils;
 import android.util.TypedValue;
 import android.view.Surface.OutOfResourcesException;
+import android.view.ThreadedRenderer.FrameDrawingCallback;
 import android.view.View.AttachInfo;
 import android.view.View.FocusDirection;
 import android.view.View.MeasureSpec;
@@ -175,6 +176,8 @@ public final class ViewRootImpl implements ViewParent,
     static final ArrayList<Runnable> sFirstDrawHandlers = new ArrayList();
     static boolean sFirstDrawComplete = false;
 
+    private FrameDrawingCallback mNextRtFrameCallback;
+
     /**
      * Callback for notifying about global configuration changes.
      */
@@ -967,6 +970,17 @@ public final class ViewRootImpl implements ViewParent,
         }
     }
 
+    /**
+     * Registers a callback to be executed when the next frame is being drawn on RenderThread. This
+     * callback will be executed on a RenderThread worker thread, and only used for the next frame
+     * and thus it will only fire once.
+     *
+     * @param callback The callback to register.
+     */
+    public void registerRtFrameCallback(FrameDrawingCallback callback) {
+        mNextRtFrameCallback = callback;
+    }
+
     private void enableHardwareAcceleration(WindowManager.LayoutParams attrs) {
         mAttachInfo.mHardwareAccelerated = false;
         mAttachInfo.mHardwareAccelerationRequested = false;
@@ -3260,7 +3274,8 @@ public final class ViewRootImpl implements ViewParent,
                     requestDrawWindow();
                 }
 
-                mAttachInfo.mThreadedRenderer.draw(mView, mAttachInfo, this);
+                mAttachInfo.mThreadedRenderer.draw(mView, mAttachInfo, this, mNextRtFrameCallback);
+                mNextRtFrameCallback = null;
             } else {
                 // If we get here with a disabled & requested hardware renderer, something went
                 // wrong (an invalidate posted right before we destroyed the hardware surface