1/* 2 * Copyright (C) 2015 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 17package android.support.v7.preference; 18 19import android.content.Context; 20import android.support.v4.content.res.TypedArrayUtils; 21import android.support.v4.view.accessibility.AccessibilityNodeInfoCompat; 22import android.support.v4.view.accessibility.AccessibilityNodeInfoCompat.CollectionItemInfoCompat; 23import android.util.AttributeSet; 24 25/** 26 * Used to group {@link Preference} objects and provide a disabled title above 27 * the group. 28 * 29 * <div class="special reference"> 30 * <h3>Developer Guides</h3> 31 * <p>For information about building a settings UI with Preferences, 32 * read the <a href="{@docRoot}guide/topics/ui/settings.html">Settings</a> 33 * guide.</p> 34 * </div> 35 */ 36public class PreferenceCategory extends PreferenceGroup { 37 private static final String TAG = "PreferenceCategory"; 38 39 public PreferenceCategory( 40 Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) { 41 super(context, attrs, defStyleAttr, defStyleRes); 42 } 43 44 public PreferenceCategory(Context context, AttributeSet attrs, int defStyleAttr) { 45 this(context, attrs, defStyleAttr, 0); 46 } 47 48 public PreferenceCategory(Context context, AttributeSet attrs) { 49 this(context, attrs, TypedArrayUtils.getAttr(context, R.attr.preferenceCategoryStyle, 50 android.R.attr.preferenceCategoryStyle)); 51 } 52 53 public PreferenceCategory(Context context) { 54 this(context, null); 55 } 56 57 @Override 58 protected boolean onPrepareAddPreference(Preference preference) { 59 if (preference instanceof PreferenceCategory) { 60 throw new IllegalArgumentException( 61 "Cannot add a " + TAG + " directly to a " + TAG); 62 } 63 64 return super.onPrepareAddPreference(preference); 65 } 66 67 @Override 68 public boolean isEnabled() { 69 return false; 70 } 71 72 @Override 73 public boolean shouldDisableDependents() { 74 return !super.isEnabled(); 75 } 76 77 @Override 78 public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfoCompat info) { 79 super.onInitializeAccessibilityNodeInfo(info); 80 81 CollectionItemInfoCompat existingItemInfo = info.getCollectionItemInfo(); 82 if (existingItemInfo == null) { 83 return; 84 } 85 86 final CollectionItemInfoCompat newItemInfo = CollectionItemInfoCompat.obtain( 87 existingItemInfo.getRowIndex(), 88 existingItemInfo.getRowSpan(), 89 existingItemInfo.getColumnIndex(), 90 existingItemInfo.getColumnSpan(), 91 true /* heading */, 92 existingItemInfo.isSelected()); 93 info.setCollectionItemInfo(newItemInfo); 94 } 95} 96