1 /* 2 * Copyright (C) 2017 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 package com.android.car.view; 17 18 import android.content.Context; 19 import android.content.res.TypedArray; 20 import android.util.AttributeSet; 21 import android.view.View; 22 import android.widget.FrameLayout; 23 24 import com.android.car.stream.ui.R; 25 26 import java.util.ArrayList; 27 import java.util.List; 28 29 /** 30 * Acts as a container to make the width of all its children not larger than the setup max width. 31 * 32 * To use MaxWidthLayout, put it as the outermost layout of all children you want to limit its max 33 * width and set the maxWidth appropriately. 34 */ 35 public class MaxWidthLayout extends FrameLayout { 36 37 // If mMaxChildrenWidth == 0, it means that it doesn't set the max width, just use the current 38 // width directly. 39 private int mMaxChildrenWidth; 40 41 public MaxWidthLayout(Context context) { 42 super(context); 43 initialize(context.obtainStyledAttributes(R.styleable.MaxWidthLayout)); 44 } 45 46 public MaxWidthLayout(Context context, AttributeSet attrs) { 47 super(context, attrs); 48 initialize(context.obtainStyledAttributes(attrs, R.styleable.MaxWidthLayout)); 49 } 50 51 public MaxWidthLayout(Context context, AttributeSet attrs, int defStyleAttr) { 52 super(context, attrs, defStyleAttr); 53 initialize(context 54 .obtainStyledAttributes(attrs, R.styleable.MaxWidthLayout, defStyleAttr, 0)); 55 } 56 57 /** 58 * Initialize MaxWidthLayout specific attributes and recycle the TypeArray. 59 */ 60 private void initialize(TypedArray ta) { 61 mMaxChildrenWidth = (int) (ta.getDimension(R.styleable.MaxWidthLayout_carMaxWidth, 0)); 62 ta.recycle(); 63 } 64 65 /** 66 * Re-measure the child width if it is greater than max width. 67 */ 68 @Override 69 protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { 70 super.onMeasure(widthMeasureSpec, heightMeasureSpec); 71 if (mMaxChildrenWidth == 0) { 72 return; 73 } 74 75 final List<View> matchParentChildren = new ArrayList<View>(); 76 for (int i = getChildCount() - 1; i >= 0; --i) { 77 final View child = getChildAt(i); 78 if (child.getVisibility() != GONE) { 79 final LayoutParams lp = (LayoutParams) child.getLayoutParams(); 80 if (lp.width == LayoutParams.MATCH_PARENT) { 81 matchParentChildren.add(child); 82 } 83 } 84 } 85 for (int i = matchParentChildren.size() - 1; i >= 0; --i) { 86 final View child = matchParentChildren.get(i); 87 final MarginLayoutParams lp = (MarginLayoutParams) child.getLayoutParams(); 88 if (child.getMeasuredWidth() > mMaxChildrenWidth) { 89 int childWidthMeasureSpec = MeasureSpec.makeMeasureSpec( 90 mMaxChildrenWidth - lp.leftMargin - lp.rightMargin, MeasureSpec.EXACTLY); 91 int childHeightMeasureSpec = MeasureSpec.makeMeasureSpec( 92 child.getMeasuredHeight(), MeasureSpec.EXACTLY); 93 child.measure(childWidthMeasureSpec, childHeightMeasureSpec); 94 } 95 } 96 } 97 } 98
