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 17 package com.android.settings.notification; 18 19 import android.content.ContentResolver; 20 import android.content.Context; 21 22 import android.database.ContentObserver; 23 import android.net.Uri; 24 import android.os.Handler; 25 import android.support.v7.preference.Preference; 26 import android.support.v7.preference.PreferenceScreen; 27 28 import com.android.internal.annotations.VisibleForTesting; 29 import com.android.settings.SettingsPreferenceFragment; 30 import com.android.settings.core.PreferenceController; 31 import com.android.settings.core.lifecycle.Lifecycle; 32 import com.android.settings.core.lifecycle.LifecycleObserver; 33 import com.android.settings.core.lifecycle.events.OnPause; 34 import com.android.settings.core.lifecycle.events.OnResume; 35 import java.util.List; 36 37 public abstract class SettingPrefController extends PreferenceController implements 38 LifecycleObserver, OnResume, OnPause { 39 40 protected static final int DEFAULT_ON = 1; 41 42 private SettingsPreferenceFragment mParent; 43 protected SettingsObserver mSettingsObserver; 44 protected SettingPref mPreference; 45 SettingPrefController(Context context, SettingsPreferenceFragment parent, Lifecycle lifecycle)46 public SettingPrefController(Context context, SettingsPreferenceFragment parent, 47 Lifecycle lifecycle) { 48 super(context); 49 mParent = parent; 50 if (lifecycle != null) { 51 lifecycle.addObserver(this); 52 } 53 } 54 55 @Override displayPreference(PreferenceScreen screen)56 public void displayPreference(PreferenceScreen screen) { 57 mPreference.init(mParent); 58 if (isAvailable()) { 59 mSettingsObserver = new SettingsObserver(); 60 } 61 } 62 63 @Override getPreferenceKey()64 public String getPreferenceKey() { 65 return mPreference.getKey(); 66 } 67 68 @Override isAvailable()69 public boolean isAvailable() { 70 return mPreference.isApplicable(mContext); 71 } 72 73 @Override updateState(Preference preference)74 public void updateState(Preference preference) { 75 mPreference.update(mContext); 76 } 77 78 @Override onResume()79 public void onResume() { 80 if (mSettingsObserver != null) { 81 mSettingsObserver.register(true /* register */); 82 } 83 } 84 85 @Override onPause()86 public void onPause() { 87 if (mSettingsObserver != null) { 88 mSettingsObserver.register(false /* register */); 89 } 90 } 91 92 @VisibleForTesting 93 final class SettingsObserver extends ContentObserver { SettingsObserver()94 public SettingsObserver() { 95 super(new Handler()); 96 } 97 register(boolean register)98 public void register(boolean register) { 99 final ContentResolver cr = mContext.getContentResolver(); 100 if (register) { 101 cr.registerContentObserver(mPreference.getUri(), false, this); 102 } else { 103 cr.unregisterContentObserver(this); 104 } 105 } 106 107 @Override onChange(boolean selfChange, Uri uri)108 public void onChange(boolean selfChange, Uri uri) { 109 super.onChange(selfChange, uri); 110 if (mPreference.getUri().equals(uri)) { 111 mPreference.update(mContext); 112 } 113 } 114 } 115 116 } 117