1 /*
2  * Copyright (C) 2023 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 package com.android.wallpaper.picker.preview.ui.view
17 
18 import android.content.Context
19 import android.util.AttributeSet
20 import com.android.wallpaper.util.WallpaperCropUtils
21 import com.davemorrissey.labs.subscaleview.SubsamplingScaleImageView
22 
23 /**
24  * A [SubsamplingScaleImageView] for wallpaper preview that scales and centers the surface to
25  * simulate the actual wallpaper surface's default system zoom.
26  */
27 class SystemScaledSubsamplingScaleImageView(context: Context, attrs: AttributeSet? = null) :
28     SubsamplingScaleImageView(context, attrs) {
onMeasurenull29     override fun onMeasure(widthMeasureSpec: Int, heightMeasureSpec: Int) {
30         super.onMeasure(widthMeasureSpec, heightMeasureSpec)
31 
32         val scale = WallpaperCropUtils.getSystemWallpaperMaximumScale(context)
33         setMeasuredDimension((measuredWidth * scale).toInt(), (measuredHeight * scale).toInt())
34     }
35 
onLayoutnull36     override fun onLayout(changed: Boolean, left: Int, top: Int, right: Int, bottom: Int) {
37         // Calculate the size of wallpaper surface based on the system zoom
38         // and scale & center the wallpaper preview to respect the zoom.
39         val scale = WallpaperCropUtils.getSystemWallpaperMaximumScale(context)
40 
41         val scaledWidth = (measuredWidth * scale).toInt()
42         val scaledHeight = (measuredHeight * scale).toInt()
43         val xCentered = (measuredWidth - scaledWidth) / 2
44         val yCentered = (measuredHeight - scaledHeight) / 2
45 
46         x = xCentered.toFloat()
47         y = yCentered.toFloat()
48     }
49 }
50