1 /*
2  * Copyright 2019 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 androidx.camera.integration.antelope
18 
19 import android.content.Context
20 import android.util.AttributeSet
21 import android.view.SurfaceView
22 import android.view.View
23 
24 /** A [SurfaceView] that can be adjusted to a specified aspect ratio. */
25 class AutoFitSurfaceView
26 @JvmOverloads
27 constructor(context: Context, attrs: AttributeSet? = null, defStyle: Int = 0) :
28     SurfaceView(context, attrs, defStyle) {
29 
30     private var ratioWidth = 0
31     private var ratioHeight = 0
32 
33     /**
34      * Sets the aspect ratio for this view. The size of the view will be measured based on the ratio
35      * calculated from the parameters. Note that the actual sizes of parameters don't matter, that
36      * is, calling setAspectRatio(2, 3) and setAspectRatio(4, 6) have the same result.
37      *
38      * @param width Relative horizontal size
39      * @param height Relative vertical size
40      */
setAspectRationull41     fun setAspectRatio(width: Int, height: Int) {
42         if (width < 0 || height < 0) {
43             throw IllegalArgumentException("Size cannot be negative.")
44         }
45         ratioWidth = width
46         ratioHeight = height
47         requestLayout()
48     }
49 
50     /**
51      * When the surface is given a new width/height, ensure that it maintains the correct aspect
52      * ratio.
53      */
onMeasurenull54     override fun onMeasure(widthMeasureSpec: Int, heightMeasureSpec: Int) {
55         super.onMeasure(widthMeasureSpec, heightMeasureSpec)
56         val width = View.MeasureSpec.getSize(widthMeasureSpec)
57         val height = View.MeasureSpec.getSize(heightMeasureSpec)
58         if (ratioWidth == 0 || ratioHeight == 0) {
59             setMeasuredDimension(width, height)
60         } else {
61             if (width < height * ratioWidth / ratioHeight) {
62                 setMeasuredDimension(width, width * ratioHeight / ratioWidth)
63             } else {
64                 setMeasuredDimension(height * ratioWidth / ratioHeight, height)
65             }
66         }
67     }
68 }
69