1 files changed, 115 insertions, 0 deletions
diff --git a/core/java/com/android/internal/transition/EpicenterClipReveal.java b/core/java/com/android/internal/transition/EpicenterClipReveal.java
new file mode 100644
index 0000000..d8a7f16
--- /dev/null
+++ b/core/java/com/android/internal/transition/EpicenterClipReveal.java
@@ -0,0 +1,115 @@
+/*
+ * Copyright (C) 2015 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.internal.transition;
+
+import android.animation.Animator;
+import android.animation.ObjectAnimator;
+import android.animation.RectEvaluator;
+import android.content.Context;
+import android.graphics.Rect;
+import android.transition.TransitionValues;
+import android.transition.Visibility;
+import android.util.AttributeSet;
+import android.view.View;
+import android.view.ViewGroup;
+
+/**
+ * EpicenterClipReveal captures the {@link View#getClipBounds()} before and
+ * after the scene change and animates between those and the epicenter bounds
+ * during a visibility transition.
+ */
+public class EpicenterClipReveal extends Visibility {
+    private static final String PROPNAME_CLIP = "android:epicenterReveal:clip";
+    private static final String PROPNAME_BOUNDS = "android:epicenterReveal:bounds";
+
+    public EpicenterClipReveal() {}
+
+    public EpicenterClipReveal(Context context, AttributeSet attrs) {
+        super(context, attrs);
+    }
+
+    @Override
+    public void captureStartValues(TransitionValues transitionValues) {
+        super.captureStartValues(transitionValues);
+        captureValues(transitionValues);
+    }
+
+    @Override
+    public void captureEndValues(TransitionValues transitionValues) {
+        super.captureEndValues(transitionValues);
+        captureValues(transitionValues);
+    }
+
+    private void captureValues(TransitionValues values) {
+        final View view = values.view;
+        if (view.getVisibility() == View.GONE) {
+            return;
+        }
+
+        final Rect clip = view.getClipBounds();
+        values.values.put(PROPNAME_CLIP, clip);
+
+        if (clip == null) {
+            final Rect bounds = new Rect(0, 0, view.getWidth(), view.getHeight());
+            values.values.put(PROPNAME_BOUNDS, bounds);
+        }
+    }
+
+    @Override
+    public Animator onAppear(ViewGroup sceneRoot, View view,
+            TransitionValues startValues, TransitionValues endValues) {
+        if (endValues == null) {
+            return null;
+        }
+
+        final Rect start = getEpicenter();
+        final Rect end = getBestRect(endValues);
+
+        // Prepare the view.
+        view.setClipBounds(start);
+
+        return createRectAnimator(view, start, end);
+    }
+
+    @Override
+    public Animator onDisappear(ViewGroup sceneRoot, View view,
+            TransitionValues startValues, TransitionValues endValues) {
+        if (startValues == null) {
+            return null;
+        }
+
+        final Rect start = getBestRect(startValues);
+        final Rect end = getEpicenter();
+
+        // Prepare the view.
+        view.setClipBounds(start);
+
+        return createRectAnimator(view, start, end);
+    }
+
+    private Rect getBestRect(TransitionValues values) {
+        final Rect clipRect = (Rect) values.values.get(PROPNAME_CLIP);
+        if (clipRect == null) {
+            return (Rect) values.values.get(PROPNAME_BOUNDS);
+        }
+        return clipRect;
+    }
+
+    private Animator createRectAnimator(View view, Rect start, Rect end) {
+        final RectEvaluator evaluator = new RectEvaluator(new Rect());
+        return ObjectAnimator.ofObject(view, "clipBounds", evaluator, start, end);
+    }
+}