| // Copyright (c) 2013 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef CHROMEOS_AUDIO_AUDIO_DEVICES_PREF_HANDLER_H_ |
| #define CHROMEOS_AUDIO_AUDIO_DEVICES_PREF_HANDLER_H_ |
| |
| #include "base/basictypes.h" |
| #include "base/memory/ref_counted.h" |
| #include "chromeos/audio/audio_pref_observer.h" |
| #include "chromeos/chromeos_export.h" |
| |
| class PrefService; |
| |
| namespace chromeos { |
| |
| struct AudioDevice; |
| |
| // Interface that handles audio preference related work, reads and writes |
| // audio preferences, and notifies AudioPrefObserver for audio preference |
| // changes. |
| class CHROMEOS_EXPORT AudioDevicesPrefHandler |
| : public base::RefCountedThreadSafe<AudioDevicesPrefHandler> { |
| public: |
| // Integer because C++ does not allow static const double in header files. |
| static const int kDefaultOutputVolumePercent = 75; |
| static const int kDefaultHdmiOutputVolumePercent = 100; |
| |
| // Gets the audio output volume value from prefs for a device. Since we can |
| // only have either a gain or a volume for a device (depending on whether it |
| // is input or output), we don't really care which value it is. |
| virtual double GetOutputVolumeValue(const AudioDevice* device) = 0; |
| virtual double GetInputGainValue(const AudioDevice* device) = 0; |
| // Sets the audio volume or gain value to prefs for a device. |
| virtual void SetVolumeGainValue(const AudioDevice& device, double value) = 0; |
| |
| // Reads the audio mute value from prefs for a device. |
| virtual bool GetMuteValue(const AudioDevice& device) = 0; |
| // Sets the audio mute value to prefs for a device. |
| virtual void SetMuteValue(const AudioDevice& device, bool mute_on) = 0; |
| |
| // Reads the audio output allowed value from prefs. |
| virtual bool GetAudioOutputAllowedValue() = 0; |
| |
| // Adds an audio preference observer. |
| virtual void AddAudioPrefObserver(AudioPrefObserver* observer) = 0; |
| // Removes an audio preference observer. |
| virtual void RemoveAudioPrefObserver(AudioPrefObserver* observer) = 0; |
| |
| protected: |
| virtual ~AudioDevicesPrefHandler() {} |
| |
| private: |
| friend class base::RefCountedThreadSafe<AudioDevicesPrefHandler>; |
| }; |
| |
| } // namespace chromeos |
| |
| #endif // CHROMEOS_AUDIO_AUDIO_DEVICES_PREF_HANDLER_H_ |