chrome/browser/chromeos/audio/audio_devices_pref_handler_impl.h

   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 CHROME_BROWSER_CHROMEOS_AUDIO_AUDIO_DEVICES_PREF_HANDLER_IMPL_H_
   6 #define CHROME_BROWSER_CHROMEOS_AUDIO_AUDIO_DEVICES_PREF_HANDLER_IMPL_H_
   7
   8 #include "base/observer_list.h"
   9 #include "base/prefs/pref_change_registrar.h"
  10 #include "base/values.h"
  11 #include "chromeos/audio/audio_devices_pref_handler.h"
  12
  13 class PrefRegistrySimple;
  14 class PrefService;
  15
  16 namespace chromeos {
  17
  18 // Class which implements AudioDevicesPrefHandler interface and register audio
  19 // preferences as well.
  20 class AudioDevicesPrefHandlerImpl : public AudioDevicesPrefHandler {
  21  public:
  22   explicit AudioDevicesPrefHandlerImpl(PrefService* local_state);
  23
  24   // Overridden from AudioDevicesPrefHandler.
  25   virtual double GetOutputVolumeValue(const AudioDevice* device) OVERRIDE;
  26   virtual double GetInputGainValue(const AudioDevice* device) OVERRIDE;
  27   virtual void SetVolumeGainValue(const AudioDevice& device,
  28                                   double value) OVERRIDE;
  29
  30   virtual bool GetMuteValue(const AudioDevice& device) OVERRIDE;
  31   virtual void SetMuteValue(const AudioDevice& device, bool mute_on) OVERRIDE;
  32
  33   virtual bool GetAudioCaptureAllowedValue() OVERRIDE;
  34   virtual bool GetAudioOutputAllowedValue() OVERRIDE;
  35
  36   virtual void AddAudioPrefObserver(AudioPrefObserver* observer) OVERRIDE;
  37   virtual void RemoveAudioPrefObserver(AudioPrefObserver* observer) OVERRIDE;
  38
  39   // Registers volume and mute preferences.
  40   static void RegisterPrefs(PrefRegistrySimple* registry);
  41
  42  protected:
  43   virtual ~AudioDevicesPrefHandlerImpl();
  44
  45  private:
  46   // Initializes the observers for the policy prefs.
  47   void InitializePrefObservers();
  48
  49   // Update and save methods for the mute preferences for all devices.
  50   void UpdateDevicesMutePref();
  51   void SaveDevicesMutePref();
  52
  53   // Update and save methods for the volume preferences for all devices.
  54   void UpdateDevicesVolumePref();
  55   void SaveDevicesVolumePref();
  56
  57   double GetVolumeGainPrefValue(const AudioDevice& device);
  58   double GetDeviceDefaultOutputVolume(const AudioDevice& device);
  59
  60   // Methods to migrate the mute and volume settings for a device from the
  61   // previous global pref value to the new per device pref value for the
  62   // current active device. If a previous global setting doesn't exist, we'll
  63   // use default values of mute = off and volume = 75%.
  64   void MigrateDeviceMuteSettings(std::string active_device);
  65   void MigrateDeviceVolumeSettings(std::string active_device);
  66
  67   // Notifies the AudioPrefObserver for audio policy pref changes.
  68   void NotifyAudioPolicyChange();
  69
  70   scoped_ptr<base::DictionaryValue> device_mute_settings_;
  71   scoped_ptr<base::DictionaryValue> device_volume_settings_;
  72
  73   PrefService* local_state_;  // not owned
  74   PrefChangeRegistrar pref_change_registrar_;
  75   ObserverList<AudioPrefObserver> observers_;
  76
  77   DISALLOW_COPY_AND_ASSIGN(AudioDevicesPrefHandlerImpl);
  78 };
  79
  80 }  // namespace chromeos
  81
  82 #endif  // CHROME_BROWSER_CHROMEOS_AUDIO_AUDIO_DEVICES_PREF_HANDLER_IMPL_H_