extensions/browser/api/audio/audio_service.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 EXTENSIONS_BROWSER_API_AUDIO_AUDIO_SERVICE_H_
   6 #define EXTENSIONS_BROWSER_API_AUDIO_AUDIO_SERVICE_H_
   7
   8 #include <string>
   9 #include <vector>
  10
  11 #include "base/callback.h"
  12 #include "base/macros.h"
  13 #include "base/memory/linked_ptr.h"
  14 #include "extensions/common/api/audio.h"
  15
  16 namespace extensions {
  17
  18 using OutputInfo = std::vector<linked_ptr<api::audio::OutputDeviceInfo>>;
  19 using InputInfo = std::vector<linked_ptr<api::audio::InputDeviceInfo>>;
  20 using DeviceIdList = std::vector<std::string>;
  21 using DeviceInfoList = std::vector<linked_ptr<api::audio::AudioDeviceInfo>>;
  22
  23 class AudioService {
  24  public:
  25   class Observer {
  26    public:
  27     // Called when anything changes to the audio device configuration.
  28     virtual void OnDeviceChanged() = 0;
  29
  30     // Called when the sound level of an active audio device changes.
  31     virtual void OnLevelChanged(const std::string& id, int level) = 0;
  32
  33     // Called when the mute state of audio input/output changes.
  34     virtual void OnMuteChanged(bool is_input, bool is_muted) = 0;
  35
  36     // Called when the audio devices change, either new devices being added, or
  37     // existing devices being removed.
  38     virtual void OnDevicesChanged(const DeviceInfoList&) = 0;
  39
  40    protected:
  41     virtual ~Observer() {}
  42   };
  43
  44   // Callback type for completing to get audio device information.
  45   typedef base::Callback<void(const OutputInfo&, const InputInfo&, bool)>
  46       GetInfoCallback;
  47
  48   // Creates a platform-specific AudioService instance.
  49   static AudioService* CreateInstance();
  50
  51   virtual ~AudioService() {}
  52
  53   // Called by listeners to this service to add/remove themselves as observers.
  54   virtual void AddObserver(Observer* observer) = 0;
  55   virtual void RemoveObserver(Observer* observer) = 0;
  56
  57   // Start to query audio device information. Should be called on UI thread.
  58   // The |callback| will be invoked once the query is completed.
  59   virtual void StartGetInfo(const GetInfoCallback& callback) = 0;
  60
  61   // Sets the active devices to the devices specified by |device_list|.
  62   // It can pass in the "complete" active device list of either input
  63   // devices, or output devices, or both. If only input devices are passed in,
  64   // it will only change the input devices' active status, output devices will
  65   // NOT be changed; similarly for the case if only output devices are passed.
  66   // If the devices specified in |new_active_ids| are already active, they will
  67   // remain active. Otherwise, the old active devices will be de-activated
  68   // before we activate the new devices with the same type(input/output).
  69   virtual void SetActiveDevices(const DeviceIdList& device_list) = 0;
  70
  71   // Set the muted and volume/gain properties of a device.
  72   virtual bool SetDeviceProperties(const std::string& device_id,
  73                                    bool muted,
  74                                    int volume,
  75                                    int gain) = 0;
  76
  77  protected:
  78   AudioService() {}
  79
  80  private:
  81   DISALLOW_COPY_AND_ASSIGN(AudioService);
  82 };
  83
  84 }  // namespace extensions
  85
  86 #endif  // EXTENSIONS_BROWSER_API_AUDIO_AUDIO_SERVICE_H_