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<core_api::audio::OutputDeviceInfo>>;
  19 using InputInfo = std::vector<linked_ptr<core_api::audio::InputDeviceInfo>>;
  20 using DeviceIdList = std::vector<std::string>;
  21
  22 class AudioService {
  23  public:
  24   class Observer {
  25    public:
  26     // Called when anything changes to the audio device configuration.
  27     virtual void OnDeviceChanged() = 0;
  28
  29    protected:
  30     virtual ~Observer() {}
  31   };
  32
  33   // Callback type for completing to get audio device information.
  34   typedef base::Callback<void(const OutputInfo&, const InputInfo&, bool)>
  35       GetInfoCallback;
  36
  37   // Creates a platform-specific AudioService instance.
  38   static AudioService* CreateInstance();
  39
  40   virtual ~AudioService() {}
  41
  42   // Called by listeners to this service to add/remove themselves as observers.
  43   virtual void AddObserver(Observer* observer) = 0;
  44   virtual void RemoveObserver(Observer* observer) = 0;
  45
  46   // Start to query audio device information. Should be called on UI thread.
  47   // The |callback| will be invoked once the query is completed.
  48   virtual void StartGetInfo(const GetInfoCallback& callback) = 0;
  49
  50   // Sets the active nodes to the nodes specified by |device_list|.
  51   // It can pass in the "complete" active node list of either input
  52   // nodes, or output nodes, or both. If only input nodes are passed in,
  53   // it will only change the input nodes' active status, output nodes will NOT
  54   // be changed; similarly for the case if only output nodes are passed.
  55   // If the nodes specified in |new_active_ids| are already active, they will
  56   // remain active. Otherwise, the old active nodes will be de-activated before
  57   // we activate the new nodes with the same type(input/output).
  58   virtual void SetActiveDevices(const DeviceIdList& device_list) = 0;
  59
  60   // Set the muted and volume/gain properties of a device.
  61   virtual bool SetDeviceProperties(const std::string& device_id,
  62                                    bool muted,
  63                                    int volume,
  64                                    int gain) = 0;
  65
  66  protected:
  67   AudioService() {}
  68
  69  private:
  70   DISALLOW_COPY_AND_ASSIGN(AudioService);
  71 };
  72
  73 }  // namespace extensions
  74
  75 #endif  // EXTENSIONS_BROWSER_API_AUDIO_AUDIO_SERVICE_H_