1 /* 2 * Copyright (C) 2016 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file 5 * except in compliance with the License. You may obtain a copy of the License at 6 * 7 * http://www.apache.org/licenses/LICENSE-2.0 8 * 9 * Unless required by applicable law or agreed to in writing, software distributed under the 10 * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 11 * KIND, either express or implied. See the License for the specific language governing 12 * permissions and limitations under the License. 13 */ 14 15 package com.android.settings.widget; 16 17 import android.content.Context; 18 import android.content.res.TypedArray; 19 import android.util.AttributeSet; 20 import android.widget.FrameLayout; 21 22 import androidx.annotation.VisibleForTesting; 23 24 import com.android.settings.R; 25 26 /** 27 * A {@link FrameLayout} with customizable aspect ratio. 28 * This is used to avoid dynamically calculating the height for the frame. Default aspect 29 * ratio will be 1 if none is set in layout attribute. 30 */ 31 public final class AspectRatioFrameLayout extends FrameLayout { 32 33 private static final float ASPECT_RATIO_CHANGE_THREASHOLD = 0.01f; 34 35 @VisibleForTesting 36 float mAspectRatio = 1.0f; 37 AspectRatioFrameLayout(Context context)38 public AspectRatioFrameLayout(Context context) { 39 this(context, null); 40 } 41 AspectRatioFrameLayout(Context context, AttributeSet attrs)42 public AspectRatioFrameLayout(Context context, AttributeSet attrs) { 43 this(context, attrs, 0); 44 } 45 AspectRatioFrameLayout(Context context, AttributeSet attrs, int defStyle)46 public AspectRatioFrameLayout(Context context, AttributeSet attrs, int defStyle) { 47 super(context, attrs, defStyle); 48 if (attrs != null) { 49 TypedArray array = 50 context.obtainStyledAttributes(attrs, R.styleable.AspectRatioFrameLayout); 51 mAspectRatio = array.getFloat( 52 R.styleable.AspectRatioFrameLayout_aspectRatio, 1.0f); 53 array.recycle(); 54 } 55 } 56 setAspectRatio(float aspectRadio)57 public void setAspectRatio(float aspectRadio) { 58 mAspectRatio = aspectRadio; 59 } 60 61 @Override onMeasure(int widthMeasureSpec, int heightMeasureSpec)62 protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { 63 super.onMeasure(widthMeasureSpec, heightMeasureSpec); 64 int width = getMeasuredWidth(); 65 int height = getMeasuredHeight(); 66 if (width == 0 || height == 0) { 67 return; 68 } 69 final float viewAspectRatio = (float) width / height; 70 final float aspectRatioDiff = mAspectRatio - viewAspectRatio; 71 if (Math.abs(aspectRatioDiff) <= ASPECT_RATIO_CHANGE_THREASHOLD) { 72 // Close enough, skip. 73 return; 74 } 75 76 width = (int) (height * mAspectRatio); 77 78 super.onMeasure(MeasureSpec.makeMeasureSpec(width, MeasureSpec.EXACTLY), 79 MeasureSpec.makeMeasureSpec(height, MeasureSpec.EXACTLY)); 80 } 81 82 } 83