1 /* 2 * Copyright (C) 2014 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.example.android.activityscenetransitionbasic; 18 19 import android.content.Context; 20 import android.util.AttributeSet; 21 import android.widget.FrameLayout; 22 23 /** 24 * {@link android.widget.FrameLayout} which forces itself to be laid out as square. 25 */ 26 public class SquareFrameLayout extends FrameLayout { 27 28 public SquareFrameLayout(Context context) { 29 super(context); 30 } 31 32 public SquareFrameLayout(Context context, AttributeSet attrs) { 33 super(context, attrs); 34 } 35 36 public SquareFrameLayout(Context context, AttributeSet attrs, int defStyleAttr) { 37 super(context, attrs, defStyleAttr); 38 } 39 40 public SquareFrameLayout(Context context, AttributeSet attrs, 41 int defStyleAttr, int defStyleRes) { 42 super(context, attrs, defStyleAttr, defStyleRes); 43 } 44 45 @Override 46 protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { 47 final int widthSize = MeasureSpec.getSize(widthMeasureSpec); 48 final int heightSize = MeasureSpec.getSize(heightMeasureSpec); 49 50 if (widthSize == 0 && heightSize == 0) { 51 // If there are no constraints on size, let FrameLayout measure 52 super.onMeasure(widthMeasureSpec, heightMeasureSpec); 53 54 // Now use the smallest of the measured dimensions for both dimensions 55 final int minSize = Math.min(getMeasuredWidth(), getMeasuredHeight()); 56 setMeasuredDimension(minSize, minSize); 57 return; 58 } 59 60 final int size; 61 if (widthSize == 0 || heightSize == 0) { 62 // If one of the dimensions has no restriction on size, set both dimensions to be the 63 // on that does 64 size = Math.max(widthSize, heightSize); 65 } else { 66 // Both dimensions have restrictions on size, set both dimensions to be the 67 // smallest of the two 68 size = Math.min(widthSize, heightSize); 69 } 70 71 final int newMeasureSpec = MeasureSpec.makeMeasureSpec(size, MeasureSpec.EXACTLY); 72 super.onMeasure(newMeasureSpec, newMeasureSpec); 73 } 74 } 75
