1 /* 2 * Copyright 2018 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.android.car.media.common; 18 19 import android.content.Context; 20 import android.content.res.TypedArray; 21 import android.util.AttributeSet; 22 import android.view.ViewGroup; 23 import android.widget.ImageView; 24 25 /** 26 * An {@link ImageView} with a fixed aspect ratio. When using this view, either width or height 27 * must be set to MATCH_PARENT. 28 */ 29 public class FixedRatioImageView extends ImageView { 30 private float mAspectRatio; 31 32 private static final float DEFAULT_ASPECT_RATIO = 1f; 33 FixedRatioImageView(Context context)34 public FixedRatioImageView(Context context) { 35 this(context, null); 36 } 37 FixedRatioImageView(Context context, AttributeSet attrs)38 public FixedRatioImageView(Context context, AttributeSet attrs) { 39 this(context, attrs, 0); 40 } 41 FixedRatioImageView(Context context, AttributeSet attrs, int defStyleAttr)42 public FixedRatioImageView(Context context, AttributeSet attrs, int defStyleAttr) { 43 super(context, attrs, defStyleAttr); 44 TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.FixedRatioImageView); 45 mAspectRatio = a.getFloat(R.styleable.FixedRatioImageView_aspect_ratio, 46 DEFAULT_ASPECT_RATIO); 47 } 48 49 /** 50 * Modify the aspect ratio of this view. 51 * 52 * @param aspectRatio a ratio between width and height. For example: 2 means this view's width 53 * would be double the height, while 0.5 means that this view's width will 54 * be half the height. 55 */ setAspectRatio(float aspectRatio)56 public void setAspectRatio(float aspectRatio) { 57 mAspectRatio = aspectRatio; 58 requestLayout(); 59 } 60 61 @Override onMeasure(int widthMeasureSpec, int heightMeasureSpec)62 protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { 63 super.onMeasure(widthMeasureSpec, heightMeasureSpec); 64 65 if (getLayoutParams().height == ViewGroup.LayoutParams.MATCH_PARENT) { 66 int height = getDefaultSize(getSuggestedMinimumHeight(), heightMeasureSpec); 67 setMeasuredDimension((int) (height * mAspectRatio), height); 68 } else if (getLayoutParams().width == ViewGroup.LayoutParams.MATCH_PARENT) { 69 int width = getDefaultSize(getSuggestedMinimumWidth(), widthMeasureSpec); 70 setMeasuredDimension(width, (int) (width / mAspectRatio)); 71 } else { 72 throw new IllegalArgumentException( 73 "Either width or height should be set to MATCH_PARENT"); 74 } 75 } 76 } 77