1 /* 2 * Copyright (C) 2013 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 package android.animation; 17 18 import android.graphics.Rect; 19 20 /** 21 * This evaluator can be used to perform type interpolation between <code>Rect</code> values. 22 */ 23 public class RectEvaluator implements TypeEvaluator<Rect> { 24 25 /** 26 * This function returns the result of linearly interpolating the start and 27 * end Rect values, with <code>fraction</code> representing the proportion 28 * between the start and end values. The calculation is a simple parametric 29 * calculation on each of the separate components in the Rect objects 30 * (left, top, right, and bottom). 31 * 32 * @param fraction The fraction from the starting to the ending values 33 * @param startValue The start Rect 34 * @param endValue The end Rect 35 * @return A linear interpolation between the start and end values, given the 36 * <code>fraction</code> parameter. 37 */ 38 @Override evaluate(float fraction, Rect startValue, Rect endValue)39 public Rect evaluate(float fraction, Rect startValue, Rect endValue) { 40 return new Rect(startValue.left + (int)((endValue.left - startValue.left) * fraction), 41 startValue.top + (int)((endValue.top - startValue.top) * fraction), 42 startValue.right + (int)((endValue.right - startValue.right) * fraction), 43 startValue.bottom + (int)((endValue.bottom - startValue.bottom) * fraction)); 44 } 45 } 46