content: /*
   * Copyright (C) 2013 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 android.transition;
  
  import android.animation.Animator;
  import android.animation.ObjectAnimator;
  import android.view.View;
  import android.view.ViewGroup;
  
  /**
   * This transition captures the rotation property of targets before and after
   * the scene change and animates any changes.
   *
   * @hide
   */
  public class Rotate extends Transition {
  
      private static final String PROPNAME_ROTATION = "android:rotate:rotation";
  
      @Override
      public void captureStartValues(TransitionValues transitionValues) {
          transitionValues.values.put(PROPNAME_ROTATION, transitionValues.view.getRotation());
      }
  
      @Override
      public void captureEndValues(TransitionValues transitionValues) {
          transitionValues.values.put(PROPNAME_ROTATION, transitionValues.view.getRotation());
      }
  
      @Override
      public Animator createAnimator(ViewGroup sceneRoot, TransitionValues startValues,
              TransitionValues endValues) {
          if (startValues == null || endValues == null) {
              return null;
          }
          final View view = endValues.view;
          float startRotation = (Float) startValues.values.get(PROPNAME_ROTATION);
          float endRotation = (Float) endValues.values.get(PROPNAME_ROTATION);
          if (startRotation != endRotation) {
              view.setRotation(startRotation);
              return ObjectAnimator.ofFloat(view, View.ROTATION,
                      startRotation, endRotation);
          }
          return null;
      }
  }
  