HardwareLayerSpringListener

rebound-android/src/main/java/com/facebook/rebound/HardwareLayerSpringListener.java

@@ -0,0 +1,66 @@
+/*
+ *  Copyright (c) 2015, Facebook, Inc.
+ *  All rights reserved.
+ *
+ *  This source code is licensed under the BSD-style license found in the
+ *  LICENSE file in the root directory of this source tree. An additional grant
+ *  of patent rights can be found in the PATENTS file in the same directory.
+ *
+ */
+
+package com.facebook.rebound;
+
+import android.view.View;
+import java.util.WeakHashMap;
+
+/**
+ * Spring Listener with Hardware Layer implementation, it's useful if
+ * you use with complex transition in your views.
+ */
+public class HardwareLayerSpringListener implements SpringListener {
+
+  /**
+   * WeakHashMap can avoid any memory leak, needs to be tested.
+   */
+  private WeakHashMap<Integer, View> weakViews = new WeakHashMap<>();
+
+  public HardwareLayerSpringListener(View... views) {
+    int countViews = views.length;
+    for(int i = 0; i < countViews; i++) {
+      weakViews.put(i, views[i]);
+    }
+  }
+
+  @Override
+  public void onSpringUpdate(Spring spring) {
+  }
+
+  /**
+   * Removes the all views of the Hardware Layer.
+   *
+   * @param spring the spring that's now resting.
+   */
+  @Override
+  public void onSpringAtRest(Spring spring) {
+    for(View view : weakViews.values()) {
+      view.setLayerType(View.LAYER_TYPE_NONE, null);
+    }
+  }
+
+  /**
+   * Set the layer type of the all views to View.LAYER_TYPE_HARDWARE.
+   *
+   * @param spring the spring that has left its resting state.
+   */
+  @Override
+  public void onSpringActivate(Spring spring) {
+    for(View view : weakViews.values()) {
+      view.setLayerType(View.LAYER_TYPE_HARDWARE, null);
+    }
+  }
+
+  @Override
+  public void onSpringEndStateChange(Spring spring) {
+  }
+
+}