1 files changed, 73 insertions, 16 deletions

diff --git a/core/java/android/view/transition/TransitionManager.java b/core/java/android/view/transition/TransitionManager.java
index 4971a92466b3..8088f6b2c23d 100644
--- a/core/java/android/view/transition/TransitionManager.java
+++ b/core/java/android/view/transition/TransitionManager.java
@@ -19,6 +19,8 @@ import android.util.ArrayMap;
 import android.view.ViewGroup;
 import android.view.ViewTreeObserver;
 
+import java.util.ArrayList;
+
 /**
  * This class manages the set of transitions that fire when there is a
  * change of {@link Scene}. To use the manager, add scenes along with
@@ -41,8 +43,10 @@ public class TransitionManager {
             new ArrayMap<Scene, ArrayMap<Scene, Transition>>();
     static ArrayMap<ViewGroup, Transition> sRunningTransitions =
             new ArrayMap<ViewGroup, Transition>();
+    private static ArrayList<ViewGroup> sPendingTransitions = new ArrayList<ViewGroup>();
+
 
-        /**
+    /**
      * Sets the transition to be used for any scene change for which no
      * other transition is explicitly set. The initial value is
      * an {@link AutoTransition} instance.
@@ -142,24 +146,15 @@ public class TransitionManager {
 
         final ViewGroup sceneRoot = scene.getSceneRoot();
 
-        Transition runningTransition = sRunningTransitions.get(sceneRoot);
-        if (runningTransition != null) {
-            runningTransition.cancelTransition();
-        }
-
-        // Capture current values
-        if (transition != null) {
-            transition.captureValues(sceneRoot, true);
-        }
-
-        // Notify previous scene that it is being exited
-        Scene previousScene = sceneRoot.getCurrentScene();
-        if (previousScene != null) {
-            previousScene.exit();
-        }
+        sceneChangeSetup(sceneRoot, transition);
 
         scene.enter();
 
+        sceneChangeRunTransition(sceneRoot, transition);
+    }
+
+    private static void sceneChangeRunTransition(final ViewGroup sceneRoot,
+            final Transition transition) {
         if (transition != null) {
             final ViewTreeObserver observer = sceneRoot.getViewTreeObserver();
             observer.addOnPreDrawListener(new ViewTreeObserver.OnPreDrawListener() {
@@ -181,6 +176,25 @@ public class TransitionManager {
         }
     }
 
+    private static void sceneChangeSetup(ViewGroup sceneRoot, Transition transition) {
+
+        Transition runningTransition = sRunningTransitions.get(sceneRoot);
+        if (runningTransition != null) {
+            runningTransition.cancelTransition();
+        }
+
+        // Capture current values
+        if (transition != null) {
+            transition.captureValues(sceneRoot, true);
+        }
+
+        // Notify previous scene that it is being exited
+        Scene previousScene = sceneRoot.getCurrentScene();
+        if (previousScene != null) {
+            previousScene.exit();
+        }
+    }
+
     /**
      * Change to the given scene, using the
      * appropriate transition for this particular scene change
@@ -272,4 +286,47 @@ public class TransitionManager {
         scene.setEnterAction(action);
         changeScene(scene, transition);
     }
+
+    /**
+     * Static utility method to animate to a new scene defined by all changes within
+     * the given scene root between calling this method and the next rendering frame.
+     * Calling this method causes TransitionManager to capture current values in the
+     * scene root and then post a request to run a transition on the next frame.
+     * At that time, the new values in the scene root will be captured and changes
+     * will be animated. There is no need to create a Scene; it is implied by
+     * changes which take place between calling this method and the next frame when
+     * the transition begins.
+     *
+     * <p>Calling this method several times before the next frame (for example, if
+     * unrelated code also wants to make dynamic changes and run a transition on
+     * the same scene root), only the first call will trigger capturing values
+     * and exiting the current scene. Subsequent calls to the method with the
+     * same scene root during the same frame will be ignored.</p>
+     *
+     * <p>Passing in <code>null</code> for the transition parameter will
+     * cause the TransitionManager to use its default transition.</p>
+     *
+     * @param sceneRoot The root of the View hierarchy to run the transition on.
+     * @param transition The transition to use for this change. A
+     * value of null causes the TransitionManager to use the default transition.
+     */
+    public static void beginDelayedTransition(final ViewGroup sceneRoot, Transition transition) {
+
+        if (!sPendingTransitions.contains(sceneRoot)) {
+            sPendingTransitions.add(sceneRoot);
+            if (transition == null) {
+                transition = sDefaultTransition;
+            }
+            final Transition finalTransition = transition;
+            sceneChangeSetup(sceneRoot, transition);
+            sceneRoot.setCurrentScene(null);
+            sceneRoot.postOnAnimation(new Runnable() {
+                @Override
+                public void run() {
+                    sPendingTransitions.remove(sceneRoot);
+                    sceneChangeRunTransition(sceneRoot, finalTransition);
+                }
+            });
+        }
+    }
 }