1 /* 2 * Copyright (C) 2019 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.developeroptions.widget; 18 19 import android.annotation.Nullable; 20 import android.content.Context; 21 import android.util.AttributeSet; 22 import android.view.Gravity; 23 import android.view.View; 24 import android.widget.LinearLayout; 25 26 import androidx.annotation.VisibleForTesting; 27 28 import com.android.settingslib.R; 29 30 /** 31 * An extension of LinearLayout that automatically switches to vertical 32 * orientation when it can't fit its child views horizontally. 33 * 34 * Main logic in this class comes from {@link androidx.appcompat.widget.ButtonBarLayout}. 35 * Compared with {@link androidx.appcompat.widget.ButtonBarLayout}, this layout won't reverse 36 * children's order and won't update the minimum height 37 */ 38 public class BottomLabelLayout extends LinearLayout { 39 private static final String TAG = "BottomLabelLayout"; 40 BottomLabelLayout(Context context, @Nullable AttributeSet attrs)41 public BottomLabelLayout(Context context, 42 @Nullable AttributeSet attrs) { 43 super(context, attrs); 44 } 45 46 @Override onMeasure(int widthMeasureSpec, int heightMeasureSpec)47 protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { 48 final int widthSize = MeasureSpec.getSize(widthMeasureSpec); 49 final boolean isStacked = isStacked(); 50 boolean needsRemeasure = false; 51 52 // If we're not stacked, make sure the measure spec is AT_MOST rather 53 // than EXACTLY. This ensures that we'll still get TOO_SMALL so that we 54 // know to stack the buttons. 55 final int initialWidthMeasureSpec; 56 if (!isStacked && MeasureSpec.getMode(widthMeasureSpec) == MeasureSpec.EXACTLY) { 57 initialWidthMeasureSpec = MeasureSpec.makeMeasureSpec(widthSize, MeasureSpec.AT_MOST); 58 59 // We'll need to remeasure again to fill excess space. 60 needsRemeasure = true; 61 } else { 62 initialWidthMeasureSpec = widthMeasureSpec; 63 } 64 65 super.onMeasure(initialWidthMeasureSpec, heightMeasureSpec); 66 if (!isStacked) { 67 final int measuredWidth = getMeasuredWidthAndState(); 68 final int measuredWidthState = measuredWidth & View.MEASURED_STATE_MASK; 69 70 if (measuredWidthState == View.MEASURED_STATE_TOO_SMALL) { 71 setStacked(true); 72 // Measure again in the new orientation. 73 needsRemeasure = true; 74 } 75 } 76 77 if (needsRemeasure) { 78 super.onMeasure(widthMeasureSpec, heightMeasureSpec); 79 } 80 81 } 82 83 @VisibleForTesting setStacked(boolean stacked)84 void setStacked(boolean stacked) { 85 setOrientation(stacked ? LinearLayout.VERTICAL : LinearLayout.HORIZONTAL); 86 setGravity(stacked ? Gravity.START : Gravity.BOTTOM); 87 88 final View spacer = findViewById(R.id.spacer); 89 if (spacer != null) { 90 spacer.setVisibility(stacked ? View.GONE : View.VISIBLE); 91 } 92 } 93 isStacked()94 private boolean isStacked() { 95 return getOrientation() == LinearLayout.VERTICAL; 96 } 97 } 98