BrightnessController.java revision cd686b5b6d4166b510df8e32138479a9559bc117 
1/*
2 * Copyright (C) 2013 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.systemui.settings;
18
19import android.content.ContentResolver;
20import android.content.Context;
21import android.content.Intent;
22import android.database.ContentObserver;
23import android.net.Uri;
24import android.os.AsyncTask;
25import android.os.Handler;
26import android.os.IPowerManager;
27import android.os.PowerManager;
28import android.os.RemoteException;
29import android.os.ServiceManager;
30import android.os.UserHandle;
31import android.provider.Settings;
32import android.provider.Settings.SettingNotFoundException;
33import android.view.IWindowManager;
34import android.widget.CompoundButton;
35import android.widget.ImageView;
36
37import java.util.ArrayList;
38
39public class BrightnessController implements ToggleSlider.Listener {
40    private static final String TAG = "StatusBar.BrightnessController";
41
42    private final int mMinimumBacklight;
43    private final int mMaximumBacklight;
44
45    private final Context mContext;
46    private final ImageView mIcon;
47    private final ToggleSlider mControl;
48    private final boolean mAutomaticAvailable;
49    private final IPowerManager mPower;
50    private final CurrentUserTracker mUserTracker;
51    private final Handler mHandler;
52    private final BrightnessObserver mBrightnessObserver;
53
54    private ArrayList<BrightnessStateChangeCallback> mChangeCallbacks =
55            new ArrayList<BrightnessStateChangeCallback>();
56
57    public interface BrightnessStateChangeCallback {
58        public void onBrightnessLevelChanged();
59    }
60
61    /** ContentObserver to watch brightness **/
62    private class BrightnessObserver extends ContentObserver {
63
64        private final Uri BRIGHTNESS_MODE_URI =
65                Settings.System.getUriFor(Settings.System.SCREEN_BRIGHTNESS_MODE);
66        private final Uri BRIGHTNESS_URI =
67                Settings.System.getUriFor(Settings.System.SCREEN_BRIGHTNESS);
68
69        public BrightnessObserver(Handler handler) {
70            super(handler);
71        }
72
73        @Override
74        public void onChange(boolean selfChange) {
75            onChange(selfChange, null);
76        }
77
78        @Override
79        public void onChange(boolean selfChange, Uri uri) {
80            if (selfChange) return;
81            if (BRIGHTNESS_MODE_URI.equals(uri)) {
82                updateMode();
83            } else if (BRIGHTNESS_URI.equals(uri)) {
84                updateSlider();
85            } else {
86                updateMode();
87                updateSlider();
88            }
89            for (BrightnessStateChangeCallback cb : mChangeCallbacks) {
90                cb.onBrightnessLevelChanged();
91            }
92        }
93
94        public void startObserving() {
95            final ContentResolver cr = mContext.getContentResolver();
96            cr.unregisterContentObserver(this);
97            cr.registerContentObserver(
98                    BRIGHTNESS_MODE_URI,
99                    false, this, UserHandle.USER_ALL);
100            cr.registerContentObserver(
101                    BRIGHTNESS_URI,
102                    false, this, UserHandle.USER_ALL);
103        }
104
105        public void stopObserving() {
106            final ContentResolver cr = mContext.getContentResolver();
107            cr.unregisterContentObserver(this);
108        }
109
110    }
111
112    public BrightnessController(Context context, ImageView icon, ToggleSlider control) {
113        mContext = context;
114        mIcon = icon;
115        mControl = control;
116        mHandler = new Handler();
117        mUserTracker = new CurrentUserTracker(mContext) {
118            @Override
119            public void onUserSwitched(int newUserId) {
120                updateMode();
121                updateSlider();
122            }
123        };
124        mBrightnessObserver = new BrightnessObserver(mHandler);
125        mBrightnessObserver.startObserving();
126
127        PowerManager pm = (PowerManager)context.getSystemService(Context.POWER_SERVICE);
128        mMinimumBacklight = pm.getMinimumScreenBrightnessSetting();
129        mMaximumBacklight = pm.getMaximumScreenBrightnessSetting();
130
131        mAutomaticAvailable = context.getResources().getBoolean(
132                com.android.internal.R.bool.config_automatic_brightness_available);
133        mPower = IPowerManager.Stub.asInterface(ServiceManager.getService("power"));
134
135        // Update the slider and mode before attaching the listener so we don't receive the
136        // onChanged notifications for the initial values.
137        updateMode();
138        updateSlider();
139
140        control.setOnChangedListener(this);
141    }
142
143    public void addStateChangedCallback(BrightnessStateChangeCallback cb) {
144        mChangeCallbacks.add(cb);
145    }
146
147    public boolean removeStateChangedCallback(BrightnessStateChangeCallback cb) {
148        return mChangeCallbacks.remove(cb);
149    }
150
151    @Override
152    public void onInit(ToggleSlider control) {
153        // Do nothing
154    }
155
156    /** Unregister all call backs, both to and from the controller */
157    public void unregisterCallbacks() {
158        mBrightnessObserver.stopObserving();
159        mChangeCallbacks.clear();
160        mUserTracker.stopTracking();
161    }
162
163    public void onChanged(ToggleSlider view, boolean tracking, boolean automatic, int value) {
164        setMode(automatic ? Settings.System.SCREEN_BRIGHTNESS_MODE_AUTOMATIC
165                : Settings.System.SCREEN_BRIGHTNESS_MODE_MANUAL);
166        updateIcon(automatic);
167        if (!automatic) {
168            final int val = value + mMinimumBacklight;
169            setBrightness(val);
170            if (!tracking) {
171                AsyncTask.execute(new Runnable() {
172                        public void run() {
173                            Settings.System.putIntForUser(mContext.getContentResolver(),
174                                    Settings.System.SCREEN_BRIGHTNESS, val,
175                                    UserHandle.USER_CURRENT);
176                        }
177                    });
178            }
179        }
180
181        for (BrightnessStateChangeCallback cb : mChangeCallbacks) {
182            cb.onBrightnessLevelChanged();
183        }
184    }
185
186    private void setMode(int mode) {
187        Settings.System.putIntForUser(mContext.getContentResolver(),
188                Settings.System.SCREEN_BRIGHTNESS_MODE, mode,
189                mUserTracker.getCurrentUserId());
190    }
191
192    private void setBrightness(int brightness) {
193        try {
194            mPower.setTemporaryScreenBrightnessSettingOverride(brightness);
195        } catch (RemoteException ex) {
196        }
197    }
198
199    private void updateIcon(boolean automatic) {
200        if (mIcon != null) {
201            mIcon.setImageResource(automatic ?
202                    com.android.systemui.R.drawable.ic_qs_brightness_auto_on :
203                    com.android.systemui.R.drawable.ic_qs_brightness_auto_off);
204        }
205    }
206
207    /** Fetch the brightness mode from the system settings and update the icon */
208    private void updateMode() {
209        if (mAutomaticAvailable) {
210            int automatic;
211            try {
212                automatic = Settings.System.getIntForUser(mContext.getContentResolver(),
213                        Settings.System.SCREEN_BRIGHTNESS_MODE,
214                        UserHandle.USER_CURRENT);
215            } catch (SettingNotFoundException snfe) {
216                automatic = 0;
217            }
218            mControl.setChecked(automatic != 0);
219            updateIcon(automatic != 0);
220        } else {
221            mControl.setChecked(false);
222            updateIcon(false /*automatic*/);
223        }
224    }
225
226    /** Fetch the brightness from the system settings and update the slider */
227    private void updateSlider() {
228        int value;
229        try {
230            value = Settings.System.getIntForUser(mContext.getContentResolver(),
231                    Settings.System.SCREEN_BRIGHTNESS,
232                    UserHandle.USER_CURRENT);
233        } catch (SettingNotFoundException ex) {
234            value = mMaximumBacklight;
235        }
236        mControl.setMax(mMaximumBacklight - mMinimumBacklight);
237        mControl.setValue(value - mMinimumBacklight);
238    }
239
240}
241