/* * Copyright (C) 2021 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.example.android.apis.view; import android.content.Context; import android.content.res.TypedArray; import android.util.AttributeSet; import android.util.Rational; import android.widget.ImageView; import com.example.android.apis.R; /** * Extended {@link ImageView} that keeps fixed aspect ratio (specified in layout file) when * one of the dimension is in exact while the other one in wrap_content size mode. */ public class FixedAspectRatioImageView extends ImageView { private final Rational mAspectRatio; public FixedAspectRatioImageView(Context context, AttributeSet attrs) { super(context, attrs); final TypedArray a = context.getTheme().obtainStyledAttributes(attrs, R.styleable.FixedAspectRatioImageView, 0, 0); try { mAspectRatio = Rational.parseRational( a.getString(R.styleable.FixedAspectRatioImageView_aspectRatio)); } finally { a.recycle(); } } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { super.onMeasure(widthMeasureSpec, heightMeasureSpec); final int width, height; if (MeasureSpec.getMode(widthMeasureSpec) == MeasureSpec.EXACTLY && MeasureSpec.getMode(heightMeasureSpec) == MeasureSpec.EXACTLY) { width = MeasureSpec.getSize(widthMeasureSpec); height = MeasureSpec.getSize(heightMeasureSpec); } else if (MeasureSpec.getMode(widthMeasureSpec) == MeasureSpec.EXACTLY) { width = MeasureSpec.getSize(widthMeasureSpec); height = (int) (width / mAspectRatio.floatValue()); } else { height = MeasureSpec.getSize(heightMeasureSpec); width = (int) (height * mAspectRatio.floatValue()); } android.util.Log.d("DebugMe", "onMeasure w=" + width + " h=" + height); setMeasuredDimension(width, height); } }