1 // Copyright 2013 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef BASE_POWER_MONITOR_POWER_MONITOR_H_ 6 #define BASE_POWER_MONITOR_POWER_MONITOR_H_ 7 8 #include "base/base_export.h" 9 #include "base/macros.h" 10 #include "base/memory/ref_counted.h" 11 #include "base/observer_list_threadsafe.h" 12 #include "base/power_monitor/power_observer.h" 13 14 namespace base { 15 16 class PowerMonitorSource; 17 18 // A class used to monitor the power state change and notify the observers about 19 // the change event. 20 class BASE_EXPORT PowerMonitor { 21 public: 22 // Takes ownership of |source|. 23 explicit PowerMonitor(std::unique_ptr<PowerMonitorSource> source); 24 ~PowerMonitor(); 25 26 // Get the process-wide PowerMonitor (if not present, returns NULL). 27 static PowerMonitor* Get(); 28 29 // Add and remove an observer. 30 // Can be called from any thread. |observer| is notified on the sequence 31 // from which it was registered. 32 // Must not be called from within a notification callback. 33 void AddObserver(PowerObserver* observer); 34 void RemoveObserver(PowerObserver* observer); 35 36 // Is the computer currently on battery power. 37 bool IsOnBatteryPower(); 38 39 private: 40 friend class PowerMonitorSource; 41 42 PowerMonitorSource* Source(); 43 44 void NotifyPowerStateChange(bool battery_in_use); 45 void NotifySuspend(); 46 void NotifyResume(); 47 48 scoped_refptr<ObserverListThreadSafe<PowerObserver>> observers_; 49 std::unique_ptr<PowerMonitorSource> source_; 50 51 DISALLOW_COPY_AND_ASSIGN(PowerMonitor); 52 }; 53 54 } // namespace base 55 56 #endif // BASE_POWER_MONITOR_POWER_MONITOR_H_ 57
