content: /*
   * Copyright (C) 2014 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.animation;
  
  import java.util.List;
  
  /**
   * This interface abstracts a collection of Keyframe objects and is called by
   * ValueAnimator to calculate values between those keyframes for a given animation.
   * @hide
   */
  public interface Keyframes extends Cloneable {
  
      /**
       * Sets the TypeEvaluator to be used when calculating animated values. This object
       * is required only for Keyframes that are not either IntKeyframes or FloatKeyframes,
       * both of which assume their own evaluator to speed up calculations with those primitive
       * types.
       *
       * @param evaluator The TypeEvaluator to be used to calculate animated values.
       */
      void setEvaluator(TypeEvaluator evaluator);
  
      /**
       * @return The value type contained by the contained Keyframes.
       */
      Class getType();
  
      /**
       * Gets the animated value, given the elapsed fraction of the animation (interpolated by the
       * animation's interpolator) and the evaluator used to calculate in-between values. This
       * function maps the input fraction to the appropriate keyframe interval and a fraction
       * between them and returns the interpolated value. Note that the input fraction may fall
       * outside the [0-1] bounds, if the animation's interpolator made that happen (e.g., a
       * spring interpolation that might send the fraction past 1.0). We handle this situation by
       * just using the two keyframes at the appropriate end when the value is outside those bounds.
       *
       * @param fraction The elapsed fraction of the animation
       * @return The animated value.
       */
      Object getValue(float fraction);
  
      /**
       * @return A list of all Keyframes contained by this. This may return null if this is
       * not made up of Keyframes.
       */
      List<Keyframe> getKeyframes();
  
      Keyframes clone();
  
      /**
       * A specialization of Keyframes that has integer primitive value calculation.
       */
      public interface IntKeyframes extends Keyframes {
  
          /**
           * Works like {@link #getValue(float)}, but returning a primitive.
           * @param fraction The elapsed fraction of the animation
           * @return The animated value.
           */
          int getIntValue(float fraction);
      }
  
      /**
       * A specialization of Keyframes that has float primitive value calculation.
       */
      public interface FloatKeyframes extends Keyframes {
  
          /**
           * Works like {@link #getValue(float)}, but returning a primitive.
           * @param fraction The elapsed fraction of the animation
           * @return The animated value.
           */
          float getFloatValue(float fraction);
      }
  }
  