Revert "Make VPA.setInterpolator(null) unset the interpolator."

This reverts commit 8cebf3a098eeff1f4b2359c4a3abdaf0e4dc494f.

Bug: 21804709
Change-Id: I4b3c2c4721b8e7dd5cb38c806bdd078344b09799

1 files changed, 11 insertions, 4 deletions

diff --git a/core/java/android/view/ViewPropertyAnimator.java b/core/java/android/view/ViewPropertyAnimator.java
index bd45007909a3..f18b7acf64f0 100644
--- a/core/java/android/view/ViewPropertyAnimator.java
+++ b/core/java/android/view/ViewPropertyAnimator.java
@@ -80,12 +80,18 @@ public class ViewPropertyAnimator {
 
     /**
      * The interpolator of the underlying Animator object. By default, we don't set the interpolator
-     * on the Animator and just use its default interpolator. If the interpolator is set to a
-     * non-null value on this Animator, then we use the interpolator that it was set to.
+     * on the Animator and just use its default interpolator. If the interpolator is ever set on
+     * this Animator, then we use the interpolator that it was set to.
      */
     private TimeInterpolator mInterpolator;
 
     /**
+     * A flag indicating whether the interpolator has been set on this object. If not, we don't set
+     * the interpolator on the underlying Animator, but instead just use its default interpolator.
+     */
+    private boolean mInterpolatorSet = false;
+
+    /**
      * Listener for the lifecycle events of the underlying ValueAnimator object.
      */
     private Animator.AnimatorListener mListener = null;
@@ -332,6 +338,7 @@ public class ViewPropertyAnimator {
      * @return This object, allowing calls to methods in this class to be chained.
      */
     public ViewPropertyAnimator setInterpolator(TimeInterpolator interpolator) {
+        mInterpolatorSet = true;
         mInterpolator = interpolator;
         return this;
     }
@@ -342,7 +349,7 @@ public class ViewPropertyAnimator {
      * @return The timing interpolator for this animation.
      */
     public TimeInterpolator getInterpolator() {
-        if (mInterpolator != null) {
+        if (mInterpolatorSet) {
             return mInterpolator;
         } else {
             // Just return the default from ValueAnimator, since that's what we'd get if
@@ -890,7 +897,7 @@ public class ViewPropertyAnimator {
         if (mDurationSet) {
             animator.setDuration(mDuration);
         }
-        if (mInterpolator != null) {
+        if (mInterpolatorSet) {
             animator.setInterpolator(mInterpolator);
         }
         animator.start();