1 // Copyright (c) 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 CHROMEOS_AUDIO_AUDIO_DEVICES_PREF_HANDLER_H_ 6 #define CHROMEOS_AUDIO_AUDIO_DEVICES_PREF_HANDLER_H_ 7 8 #include "base/basictypes.h" 9 #include "base/memory/ref_counted.h" 10 #include "chromeos/audio/audio_pref_observer.h" 11 #include "chromeos/chromeos_export.h" 12 13 class PrefService; 14 15 namespace chromeos { 16 17 struct AudioDevice; 18 19 // Interface that handles audio preference related work, reads and writes 20 // audio preferences, and notifies AudioPrefObserver for audio preference 21 // changes. 22 class CHROMEOS_EXPORT AudioDevicesPrefHandler 23 : public base::RefCountedThreadSafe<AudioDevicesPrefHandler> { 24 public: 25 // Gets the audio output volume value from prefs for a device. Since we can 26 // only have either a gain or a volume for a device (depending on whether it 27 // is input or output), we don't really care which value it is. 28 virtual double GetVolumeGainValue(const AudioDevice& device) = 0; 29 // Sets the audio volume or gain value to prefs for a device. 30 virtual void SetVolumeGainValue(const AudioDevice& device, double value) = 0; 31 32 // Reads the audio mute value from prefs for a device. 33 virtual bool GetMuteValue(const AudioDevice& device) = 0; 34 // Sets the audio mute value to prefs for a device. 35 virtual void SetMuteValue(const AudioDevice& device, bool mute_on) = 0; 36 37 // Reads the audio capture allowed value from prefs. 38 virtual bool GetAudioCaptureAllowedValue() = 0; 39 // Reads the audio output allowed value from prefs. 40 virtual bool GetAudioOutputAllowedValue() = 0; 41 42 // Adds an audio preference observer. 43 virtual void AddAudioPrefObserver(AudioPrefObserver* observer) = 0; 44 // Removes an audio preference observer. 45 virtual void RemoveAudioPrefObserver(AudioPrefObserver* observer) = 0; 46 47 // Creates the instance. 48 static AudioDevicesPrefHandler* Create(PrefService* local_state); 49 50 protected: 51 virtual ~AudioDevicesPrefHandler() {} 52 53 private: 54 friend class base::RefCountedThreadSafe<AudioDevicesPrefHandler>; 55 }; 56 57 } // namespace chromeos 58 59 #endif // CHROMEOS_AUDIO_AUDIO_DEVICES_PREF_HANDLER_H_ 60