CycleInterpolator.java revision 54b6cfa9a9e5b861a9930af873580d6dc20f773c 
1/*
2 * Copyright (C) 2007 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
17package android.view.animation;
18
19import android.content.Context;
20import android.content.res.TypedArray;
21import android.util.AttributeSet;
22
23/**
24 * Repeats the animation for a specified number of cycles. The
25 * rate of change follows a sinusoidal pattern.
26 *
27 */
28public class CycleInterpolator implements Interpolator {
29    public CycleInterpolator(float cycles) {
30        mCycles = cycles;
31    }
32
33    public CycleInterpolator(Context context, AttributeSet attrs) {
34        TypedArray a =
35            context.obtainStyledAttributes(attrs, com.android.internal.R.styleable.CycleInterpolator);
36
37        mCycles = a.getFloat(com.android.internal.R.styleable.CycleInterpolator_cycles, 1.0f);
38
39        a.recycle();
40    }
41
42    public float getInterpolation(float input) {
43        return (float)(Math.sin(2 * mCycles * Math.PI * input));
44    }
45
46    private float mCycles;
47}
48