1 /* 2 * Copyright (C) 2016 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.google.android.setupdesign.view; 18 19 import android.annotation.TargetApi; 20 import android.content.Context; 21 import android.content.res.TypedArray; 22 import android.os.Build.VERSION_CODES; 23 import android.util.AttributeSet; 24 import android.widget.FrameLayout; 25 import com.google.android.setupdesign.R; 26 27 /** 28 * A FrameLayout subclass that has an "intrinsic size", which is the size it wants to be if that is 29 * within the constraints given by the parent. The intrinsic size can be set with the {@code 30 * android:width} and {@code android:height} attributes in XML. 31 * 32 * <p>Note that for the intrinsic size to be meaningful, {@code android:layout_width} and/or {@code 33 * android:layout_height} will need to be {@code wrap_content}. 34 */ 35 public class IntrinsicSizeFrameLayout extends FrameLayout { 36 37 private int intrinsicHeight = 0; 38 private int intrinsicWidth = 0; 39 IntrinsicSizeFrameLayout(Context context)40 public IntrinsicSizeFrameLayout(Context context) { 41 super(context); 42 init(context, null, 0); 43 } 44 IntrinsicSizeFrameLayout(Context context, AttributeSet attrs)45 public IntrinsicSizeFrameLayout(Context context, AttributeSet attrs) { 46 super(context, attrs); 47 init(context, attrs, 0); 48 } 49 50 @TargetApi(VERSION_CODES.HONEYCOMB) IntrinsicSizeFrameLayout(Context context, AttributeSet attrs, int defStyleAttr)51 public IntrinsicSizeFrameLayout(Context context, AttributeSet attrs, int defStyleAttr) { 52 super(context, attrs, defStyleAttr); 53 init(context, attrs, defStyleAttr); 54 } 55 init(Context context, AttributeSet attrs, int defStyleAttr)56 private void init(Context context, AttributeSet attrs, int defStyleAttr) { 57 final TypedArray a = 58 context.obtainStyledAttributes( 59 attrs, R.styleable.SudIntrinsicSizeFrameLayout, defStyleAttr, 0); 60 intrinsicHeight = 61 a.getDimensionPixelSize(R.styleable.SudIntrinsicSizeFrameLayout_android_height, 0); 62 intrinsicWidth = 63 a.getDimensionPixelSize(R.styleable.SudIntrinsicSizeFrameLayout_android_width, 0); 64 a.recycle(); 65 } 66 67 @Override onMeasure(int widthMeasureSpec, int heightMeasureSpec)68 protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { 69 super.onMeasure( 70 getIntrinsicMeasureSpec(widthMeasureSpec, intrinsicWidth), 71 getIntrinsicMeasureSpec(heightMeasureSpec, intrinsicHeight)); 72 } 73 getIntrinsicMeasureSpec(int measureSpec, int intrinsicSize)74 private int getIntrinsicMeasureSpec(int measureSpec, int intrinsicSize) { 75 if (intrinsicSize <= 0) { 76 // Intrinsic size is not set, just return the original spec 77 return measureSpec; 78 } 79 final int mode = MeasureSpec.getMode(measureSpec); 80 final int size = MeasureSpec.getSize(measureSpec); 81 if (mode == MeasureSpec.UNSPECIFIED) { 82 // Parent did not give any constraint, so we'll be the intrinsic size 83 return MeasureSpec.makeMeasureSpec(intrinsicHeight, MeasureSpec.EXACTLY); 84 } else if (mode == MeasureSpec.AT_MOST) { 85 // If intrinsic size is within parents constraint, take the intrinsic size. 86 // Otherwise take the parents size because that's closest to the intrinsic size. 87 return MeasureSpec.makeMeasureSpec(Math.min(size, intrinsicHeight), MeasureSpec.EXACTLY); 88 } 89 // Parent specified EXACTLY, or in all other cases, just return the original spec 90 return measureSpec; 91 } 92 } 93