1 /*
2  * Copyright 2014 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 com.example.android.camera2basic;
18 
19 import android.content.Context;
20 import android.util.AttributeSet;
21 import android.view.TextureView;
22 
23 /**
24  * A {@link TextureView} that can be adjusted to a specified aspect ratio.
25  */
26 public class AutoFitTextureView extends TextureView {
27 
28     private int mRatioWidth = 0;
29     private int mRatioHeight = 0;
30 
AutoFitTextureView(Context context)31     public AutoFitTextureView(Context context) {
32         this(context, null);
33     }
34 
AutoFitTextureView(Context context, AttributeSet attrs)35     public AutoFitTextureView(Context context, AttributeSet attrs) {
36         this(context, attrs, 0);
37     }
38 
AutoFitTextureView(Context context, AttributeSet attrs, int defStyle)39     public AutoFitTextureView(Context context, AttributeSet attrs, int defStyle) {
40         super(context, attrs, defStyle);
41     }
42 
43     /**
44      * Sets the aspect ratio for this view. The size of the view will be measured based on the ratio
45      * calculated from the parameters. Note that the actual sizes of parameters don't matter, that
46      * is, calling setAspectRatio(2, 3) and setAspectRatio(4, 6) make the same result.
47      *
48      * @param width  Relative horizontal size
49      * @param height Relative vertical size
50      */
setAspectRatio(int width, int height)51     public void setAspectRatio(int width, int height) {
52         if (width < 0 || height < 0) {
53             throw new IllegalArgumentException("Size cannot be negative.");
54         }
55         mRatioWidth = width;
56         mRatioHeight = height;
57         requestLayout();
58     }
59 
60     @Override
onMeasure(int widthMeasureSpec, int heightMeasureSpec)61     protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
62         super.onMeasure(widthMeasureSpec, heightMeasureSpec);
63         int width = MeasureSpec.getSize(widthMeasureSpec);
64         int height = MeasureSpec.getSize(heightMeasureSpec);
65         if (0 == mRatioWidth || 0 == mRatioHeight) {
66             setMeasuredDimension(width, height);
67         } else {
68             if (width < height * mRatioWidth / mRatioHeight) {
69                 setMeasuredDimension(width, width * mRatioHeight / mRatioWidth);
70             } else {
71                 setMeasuredDimension(height * mRatioWidth / mRatioHeight, height);
72             }
73         }
74     }
75 
76 }
77