Add updateListener to ViewPropertyAnimator

New method setUpdateListener() on ViewPropertyAnimator that will
send out update events to the provided listener.

Issue #10118113 Offer update listener on ViewPropertyAnimator

Change-Id: Ib9f8fc6dbbc3c1c58113246d9a3b01e7ac27b14c

1 files changed, 32 insertions, 2 deletions

diff --git a/core/java/android/view/ViewPropertyAnimator.java b/core/java/android/view/ViewPropertyAnimator.java
index e6bf420..cea7e49 100644
--- a/core/java/android/view/ViewPropertyAnimator.java
+++ b/core/java/android/view/ViewPropertyAnimator.java
@@ -93,11 +93,16 @@ public class ViewPropertyAnimator {
     private boolean mInterpolatorSet = false;
 
     /**
-     * Listener for the lifecycle events of the underlying 
+     * Listener for the lifecycle events of the underlying ValueAnimator object.
      */
     private Animator.AnimatorListener mListener = null;
 
     /**
+     * Listener for the update events of the underlying ValueAnimator object.
+     */
+    private ValueAnimator.AnimatorUpdateListener mUpdateListener = null;
+
+    /**
      * A lazily-created ValueAnimator used in order to get some default animator properties
      * (duration, start delay, interpolator, etc.).
      */
@@ -353,7 +358,10 @@ public class ViewPropertyAnimator {
      * Sets a listener for events in the underlying Animators that run the property
      * animations.
      *
-     * @param listener The listener to be called with AnimatorListener events.
+     * @see Animator.AnimatorListener
+     *
+     * @param listener The listener to be called with AnimatorListener events. A value of
+     * <code>null</code> removes any existing listener.
      * @return This object, allowing calls to methods in this class to be chained.
      */
     public ViewPropertyAnimator setListener(Animator.AnimatorListener listener) {
@@ -362,6 +370,25 @@ public class ViewPropertyAnimator {
     }
 
     /**
+     * Sets a listener for update events in the underlying ValueAnimator that runs
+     * the property animations. Note that the underlying animator is animating between
+     * 0 and 1 (these values are then turned into the actual property values internally
+     * by ViewPropertyAnimator). So the animator cannot give information on the current
+     * values of the properties being animated by this ViewPropertyAnimator, although
+     * the view object itself can be queried to get the current values.
+     *
+     * @see android.animation.ValueAnimator.AnimatorUpdateListener
+     *
+     * @param listener The listener to be called with update events. A value of
+     * <code>null</code> removes any existing listener.
+     * @return This object, allowing calls to methods in this class to be chained.
+     */
+    public ViewPropertyAnimator setUpdateListener(ValueAnimator.AnimatorUpdateListener listener) {
+        mUpdateListener = listener;
+        return this;
+    }
+
+    /**
      * Starts the currently pending property animations immediately. Calling <code>start()</code>
      * is optional because all animations start automatically at the next opportunity. However,
      * if the animations are needed to start immediately and synchronously (not at the time when
@@ -1073,6 +1100,9 @@ public class ViewPropertyAnimator {
             } else {
                 mView.invalidateViewProperty(false, false);
             }
+            if (mUpdateListener != null) {
+                mUpdateListener.onAnimationUpdate(animation);
+            }
         }
     }
 }