1 files changed, 105 insertions, 0 deletions
diff --git a/java/com/android/newbubble/RoundedRectRevealOutlineProvider.java b/java/com/android/newbubble/RoundedRectRevealOutlineProvider.java
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+++ b/java/com/android/newbubble/RoundedRectRevealOutlineProvider.java
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+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License
+ */
+
+package com.android.newbubble;
+
+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;
+
+/**
+ * A {@link ViewOutlineProvider} that provides an outline that interpolates between two radii and
+ * two {@link Rect}s.
+ *
+ * <p>An example usage of this provider is an outline that starts out as a circle and ends as a
+ * rounded rectangle.
+ */
+public class RoundedRectRevealOutlineProvider extends ViewOutlineProvider {
+  private final float mStartRadius;
+  private final float mEndRadius;
+
+  private final Rect mStartRect;
+  private final Rect mEndRect;
+
+  private final Rect mOutline;
+  private float mOutlineRadius;
+
+  public RoundedRectRevealOutlineProvider(
+      float startRadius, float endRadius, Rect startRect, Rect endRect) {
+    mStartRadius = startRadius;
+    mEndRadius = endRadius;
+    mStartRect = startRect;
+    mEndRect = endRect;
+
+    mOutline = new Rect();
+  }
+
+  @Override
+  public void getOutline(View v, Outline outline) {
+    outline.setRoundRect(mOutline, mOutlineRadius);
+  }
+
+  /** Sets the progress, from 0 to 1, of the reveal animation. */
+  public void setProgress(float progress) {
+    mOutlineRadius = (1 - progress) * mStartRadius + progress * mEndRadius;
+
+    mOutline.left = (int) ((1 - progress) * mStartRect.left + progress * mEndRect.left);
+    mOutline.top = (int) ((1 - progress) * mStartRect.top + progress * mEndRect.top);
+    mOutline.right = (int) ((1 - progress) * mStartRect.right + progress * mEndRect.right);
+    mOutline.bottom = (int) ((1 - progress) * mStartRect.bottom + progress * mEndRect.bottom);
+  }
+
+  ValueAnimator createRevealAnimator(final View revealView, boolean isReversed) {
+    ValueAnimator valueAnimator =
+        isReversed ? ValueAnimator.ofFloat(1f, 0f) : ValueAnimator.ofFloat(0f, 1f);
+
+    valueAnimator.addListener(
+        new AnimatorListenerAdapter() {
+          private boolean mWasCanceled = false;
+
+          @Override
+          public void onAnimationStart(Animator animation) {
+            revealView.setOutlineProvider(RoundedRectRevealOutlineProvider.this);
+            revealView.setClipToOutline(true);
+          }
+
+          @Override
+          public void onAnimationCancel(Animator animation) {
+            mWasCanceled = true;
+          }
+
+          @Override
+          public void onAnimationEnd(Animator animation) {
+            if (!mWasCanceled) {
+              revealView.setOutlineProvider(ViewOutlineProvider.BACKGROUND);
+              revealView.setClipToOutline(false);
+            }
+          }
+        });
+
+    valueAnimator.addUpdateListener(
+        (currentValueAnimator) -> {
+          float progress = (Float) currentValueAnimator.getAnimatedValue();
+          setProgress(progress);
+          revealView.invalidateOutline();
+        });
+    return valueAnimator;
+  }
+}