Add ability to override global duration scale on ValueAnimator

This is needed as window animations are being ported over to use
ValueAnimator, and thus ValueAnimator need to ability to support
custom duration scales per object.

Test: ValueAnimatorTests
Bug: 64674361
Change-Id: Iea8d673b66e52866929174bbf6ca4a7ae882807b

diff --git a/core/java/android/animation/ValueAnimator.java b/core/java/android/animation/ValueAnimator.java
index ee89ca8..cc95eb6 100644 (file)
--- a/core/java/android/animation/ValueAnimator.java
+++ b/core/java/android/animation/ValueAnimator.java
@@ -254,6 +254,11 @@ public class ValueAnimator extends Animator implements AnimationHandler.Animatio
     HashMap<String, PropertyValuesHolder> mValuesMap;
 
     /**
+     * If set to non-negative value, this will override {@link #sDurationScale}.
+     */
+    private float mDurationScale = -1f;
+
+    /**
      * Public constants
      */
 
@@ -579,8 +584,23 @@ public class ValueAnimator extends Animator implements AnimationHandler.Animatio
         return this;
     }
 
+    /**
+     * Overrides the global duration scale by a custom value.
+     *
+     * @param durationScale The duration scale to set; or {@code -1f} to use the global duration
+     *                      scale.
+     * @hide
+     */
+    public void overrideDurationScale(float durationScale) {
+        mDurationScale = durationScale;
+    }
+
+    private float resolveDurationScale() {
+        return mDurationScale >= 0f ? mDurationScale : sDurationScale;
+    }
+
     private long getScaledDuration() {
-        return (long)(mDuration * sDurationScale);
+        return (long)(mDuration * resolveDurationScale());
     }
 
     /**
@@ -735,7 +755,10 @@ public class ValueAnimator extends Animator implements AnimationHandler.Animatio
         if (mSeekFraction >= 0) {
             return (long) (mDuration * mSeekFraction);
         }
-        float durationScale = sDurationScale == 0 ? 1 : sDurationScale;
+        float durationScale = resolveDurationScale();
+        if (durationScale == 0f) {
+            durationScale = 1f;
+        }
         return (long) ((AnimationUtils.currentAnimationTimeMillis() - mStartTime) / durationScale);
     }
 
@@ -1397,7 +1420,9 @@ public class ValueAnimator extends Animator implements AnimationHandler.Animatio
         if (mStartTime < 0) {
             // First frame. If there is start delay, start delay count down will happen *after* this
             // frame.
-            mStartTime = mReversing ? frameTime : frameTime + (long) (mStartDelay * sDurationScale);
+            mStartTime = mReversing
+                    ? frameTime
+                    : frameTime + (long) (mStartDelay * resolveDurationScale());
         }
 
         // Handle pause/resume