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 
17 package android.view.animation;
18 
19 import android.content.Context;
20 import android.content.res.Resources;
21 import android.content.res.Resources.Theme;
22 import android.content.res.TypedArray;
23 import android.util.AttributeSet;
24 
25 import com.android.internal.R;
26 import com.android.internal.view.animation.HasNativeInterpolator;
27 import com.android.internal.view.animation.NativeInterpolatorFactory;
28 import com.android.internal.view.animation.NativeInterpolatorFactoryHelper;
29 
30 /**
31  * Repeats the animation for a specified number of cycles. The
32  * rate of change follows a sinusoidal pattern.
33  *
34  */
35 @HasNativeInterpolator
36 public class CycleInterpolator extends BaseInterpolator implements NativeInterpolatorFactory {
CycleInterpolator(float cycles)37     public CycleInterpolator(float cycles) {
38         mCycles = cycles;
39     }
40 
CycleInterpolator(Context context, AttributeSet attrs)41     public CycleInterpolator(Context context, AttributeSet attrs) {
42         this(context.getResources(), context.getTheme(), attrs);
43     }
44 
45     /** @hide */
CycleInterpolator(Resources resources, Theme theme, AttributeSet attrs)46     public CycleInterpolator(Resources resources, Theme theme, AttributeSet attrs) {
47         TypedArray a;
48         if (theme != null) {
49             a = theme.obtainStyledAttributes(attrs, R.styleable.CycleInterpolator, 0, 0);
50         } else {
51             a = resources.obtainAttributes(attrs, R.styleable.CycleInterpolator);
52         }
53 
54         mCycles = a.getFloat(R.styleable.CycleInterpolator_cycles, 1.0f);
55         setChangingConfiguration(a.getChangingConfigurations());
56         a.recycle();
57     }
58 
getInterpolation(float input)59     public float getInterpolation(float input) {
60         return (float)(Math.sin(2 * mCycles * Math.PI * input));
61     }
62 
63     private float mCycles;
64 
65     /** @hide */
66     @Override
createNativeInterpolator()67     public long createNativeInterpolator() {
68         return NativeInterpolatorFactoryHelper.createCycleInterpolator(mCycles);
69     }
70 }
71