1 files changed, 90 insertions, 0 deletions
diff --git a/src/com/android/launcher3/anim/RevealOutlineAnimation.java b/src/com/android/launcher3/anim/RevealOutlineAnimation.java
new file mode 100644
index 000000000..51d00d947
--- /dev/null
+++ b/src/com/android/launcher3/anim/RevealOutlineAnimation.java
@@ -0,0 +1,90 @@
+package com.android.launcher3.anim;
+
+import android.animation.Animator;
+import android.animation.AnimatorListenerAdapter;
+import android.animation.ValueAnimator;
+import android.graphics.Outline;
+import android.graphics.Rect;
+import android.view.View;
+import android.view.ViewOutlineProvider;
+
+import com.android.launcher3.Utilities;
+
+/**
+ * A {@link ViewOutlineProvider} that has helper functions to create reveal animations.
+ * This class should be extended so that subclasses can define the reveal shape as the
+ * animation progresses from 0 to 1.
+ */
+public abstract class RevealOutlineAnimation extends ViewOutlineProvider {
+    protected Rect mOutline;
+    protected float mOutlineRadius;
+
+    public RevealOutlineAnimation() {
+        mOutline = new Rect();
+    }
+
+    /** Returns whether elevation should be removed for the duration of the reveal animation. */
+    abstract boolean shouldRemoveElevationDuringAnimation();
+    /** Sets the progress, from 0 to 1, of the reveal animation. */
+    abstract void setProgress(float progress);
+
+    public ValueAnimator createRevealAnimator(final View revealView) {
+        return createRevealAnimator(revealView, false);
+    }
+
+    public ValueAnimator createRevealAnimator(final View revealView, boolean isReversed) {
+        ValueAnimator va =
+                isReversed ? ValueAnimator.ofFloat(1f, 0f) : ValueAnimator.ofFloat(0f, 1f);
+        final float elevation = revealView.getElevation();
+
+        va.addListener(new AnimatorListenerAdapter() {
+            private boolean mWasCanceled = false;
+
+            public void onAnimationStart(Animator animation) {
+                revealView.setOutlineProvider(RevealOutlineAnimation.this);
+                revealView.setClipToOutline(true);
+                if (shouldRemoveElevationDuringAnimation()) {
+                    revealView.setTranslationZ(-elevation);
+                }
+            }
+
+            @Override
+            public void onAnimationCancel(Animator animation) {
+                mWasCanceled = true;
+            }
+
+            public void onAnimationEnd(Animator animation) {
+                if (!mWasCanceled) {
+                    revealView.setOutlineProvider(ViewOutlineProvider.BACKGROUND);
+                    revealView.setClipToOutline(false);
+                    if (shouldRemoveElevationDuringAnimation()) {
+                        revealView.setTranslationZ(0);
+                    }
+                }
+            }
+
+        });
+
+        va.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
+            @Override
+            public void onAnimationUpdate(ValueAnimator arg0) {
+                float progress = (Float) arg0.getAnimatedValue();
+                setProgress(progress);
+                revealView.invalidateOutline();
+                if (!Utilities.ATLEAST_LOLLIPOP_MR1) {
+                    revealView.invalidate();
+                }
+            }
+        });
+        return va;
+    }
+
+    @Override
+    public void getOutline(View v, Outline outline) {
+        outline.setRoundRect(mOutline, mOutlineRadius);
+    }
+
+    public float getRadius() {
+        return mOutlineRadius;
+    }
+}