1 /*
2  * Copyright (C) 2015 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.compat.annotation.UnsupportedAppUsage;
20 import android.graphics.Matrix;
21 
22 /**
23  * Special case of TranslateAnimation that translates only vertically, picking up the
24  * horizontal values from whatever is set on the Transformation already. When used in
25  * conjunction with a TranslateXAnimation, allows independent animation of x and y
26  * position.
27  * @hide
28  */
29 public class TranslateYAnimation extends TranslateAnimation {
30     float[] mTmpValues = new float[9];
31 
32     /**
33      * Constructor. Passes in 0 for the x parameters of TranslateAnimation
34      */
TranslateYAnimation(float fromYDelta, float toYDelta)35     public TranslateYAnimation(float fromYDelta, float toYDelta) {
36         super(0, 0, fromYDelta, toYDelta);
37     }
38 
39     /**
40      * Constructor. Passes in 0 for the x parameters of TranslateAnimation
41      */
42     @UnsupportedAppUsage
TranslateYAnimation(int fromYType, float fromYValue, int toYType, float toYValue)43     public TranslateYAnimation(int fromYType, float fromYValue, int toYType, float toYValue) {
44         super(ABSOLUTE, 0, ABSOLUTE, 0, fromYType, fromYValue, toYType, toYValue);
45     }
46 
47     /**
48      * Calculates and sets y translation values on given transformation.
49      */
50     @Override
applyTransformation(float interpolatedTime, Transformation t)51     protected void applyTransformation(float interpolatedTime, Transformation t) {
52         Matrix m = t.getMatrix();
53         m.getValues(mTmpValues);
54         float dy = mFromYDelta + ((mToYDelta - mFromYDelta) * interpolatedTime);
55         t.getMatrix().setTranslate(mTmpValues[Matrix.MTRANS_X], dy);
56     }
57 }
58