CoreSettingsObserver.java revision ccb2a086fe0de77a4e3277454cb4a66f8e7dc57d 
1/*
2 * Copyright (C) 2006-2011 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 com.android.server.am;
18
19import android.content.Context;
20import android.database.ContentObserver;
21import android.net.Uri;
22import android.os.Bundle;
23import android.provider.Settings;
24import android.provider.Settings.SettingNotFoundException;
25import android.util.Log;
26
27import java.util.HashMap;
28import java.util.Map;
29
30/**
31 * Helper class for watching a set of core settings which the framework
32 * propagates to application processes to avoid multiple lookups and potentially
33 * disk I/O operations. Note: This class assumes that all core settings reside
34 * in {@link Settings.Secure}.
35 */
36final class CoreSettingsObserver extends ContentObserver {
37    private static final String LOG_TAG = CoreSettingsObserver.class.getSimpleName();
38
39    // mapping form property name to its type
40    private static final Map<String, Class<?>> sSecureSettingToTypeMap = new HashMap<
41            String, Class<?>>();
42    private static final Map<String, Class<?>> sSystemSettingToTypeMap = new HashMap<
43            String, Class<?>>();
44    static {
45        sSecureSettingToTypeMap.put(Settings.Secure.LONG_PRESS_TIMEOUT, int.class);
46        // add other secure settings here...
47
48        sSystemSettingToTypeMap.put(Settings.System.TIME_12_24, String.class);
49        // add other system settings here...
50    }
51
52    private final Bundle mCoreSettings = new Bundle();
53
54    private final ActivityManagerService mActivityManagerService;
55
56    public CoreSettingsObserver(ActivityManagerService activityManagerService) {
57        super(activityManagerService.mHandler);
58        mActivityManagerService = activityManagerService;
59        beginObserveCoreSettings();
60        sendCoreSettings();
61    }
62
63    public Bundle getCoreSettingsLocked() {
64        return (Bundle) mCoreSettings.clone();
65    }
66
67    @Override
68    public void onChange(boolean selfChange) {
69        synchronized (mActivityManagerService) {
70            sendCoreSettings();
71        }
72    }
73
74    private void sendCoreSettings() {
75        populateSettings(mCoreSettings, sSecureSettingToTypeMap);
76        populateSettings(mCoreSettings, sSystemSettingToTypeMap);
77        mActivityManagerService.onCoreSettingsChange(mCoreSettings);
78    }
79
80    private void beginObserveCoreSettings() {
81        for (String setting : sSecureSettingToTypeMap.keySet()) {
82            Uri uri = Settings.Secure.getUriFor(setting);
83            mActivityManagerService.mContext.getContentResolver().registerContentObserver(
84                    uri, false, this);
85        }
86
87        for (String setting : sSystemSettingToTypeMap.keySet()) {
88            Uri uri = Settings.System.getUriFor(setting);
89            mActivityManagerService.mContext.getContentResolver().registerContentObserver(
90                    uri, false, this);
91        }
92    }
93
94    private void populateSettings(Bundle snapshot, Map<String, Class<?>> map) {
95        Context context = mActivityManagerService.mContext;
96        for (Map.Entry<String, Class<?>> entry : map.entrySet()) {
97            String setting = entry.getKey();
98            Class<?> type = entry.getValue();
99            try {
100                if (type == String.class) {
101                    final String value;
102                    if (map == sSecureSettingToTypeMap) {
103                        value = Settings.Secure.getString(context.getContentResolver(), setting);
104                    } else {
105                        value = Settings.System.getString(context.getContentResolver(), setting);
106                    }
107                    snapshot.putString(setting, value);
108                } else if (type == int.class) {
109                    final int value;
110                    if (map == sSecureSettingToTypeMap) {
111                        value = Settings.Secure.getInt(context.getContentResolver(), setting);
112                    } else {
113                        value = Settings.System.getInt(context.getContentResolver(), setting);
114                    }
115                    snapshot.putInt(setting, value);
116                } else if (type == float.class) {
117                    final float value;
118                    if (map == sSecureSettingToTypeMap) {
119                        value = Settings.Secure.getFloat(context.getContentResolver(), setting);
120                    } else {
121                        value = Settings.System.getFloat(context.getContentResolver(), setting);
122                    }
123                    snapshot.putFloat(setting, value);
124                } else if (type == long.class) {
125                    final long value;
126                    if (map == sSecureSettingToTypeMap) {
127                        value = Settings.Secure.getLong(context.getContentResolver(), setting);
128                    } else {
129                        value = Settings.System.getLong(context.getContentResolver(), setting);
130                    }
131                    snapshot.putLong(setting, value);
132                }
133            } catch (SettingNotFoundException snfe) {
134                Log.w(LOG_TAG, "Cannot find setting \"" + setting + "\"", snfe);
135            }
136        }
137    }
138}
139