chromeos/dbus/amplifier_client.h

   1 // Copyright 2015 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_DBUS_AMPLIFIER_CLIENT_H_
   6 #define CHROMEOS_DBUS_AMPLIFIER_CLIENT_H_
   7
   8 #include "base/basictypes.h"
   9 #include "chromeos/chromeos_export.h"
  10 #include "chromeos/dbus/dbus_client.h"
  11 #include "chromeos/dbus/dbus_method_call_status.h"
  12
  13 namespace chromeos {
  14
  15 // A DBus client class for the org.chromium.Amplifier service.
  16 class CHROMEOS_EXPORT AmplifierClient : public DBusClient {
  17  public:
  18   // Interface for observing amplifier events from an amplifier client.
  19   class Observer {
  20    public:
  21     virtual ~Observer() {}
  22     // Called when the Error signal is received.
  23     virtual void OnError(int32 error_code) = 0;
  24   };
  25
  26   ~AmplifierClient() override;
  27
  28   // Adds and removes observers for amplifier events.
  29   virtual void AddObserver(Observer* observer) = 0;
  30   virtual void RemoveObserver(Observer* observer) = 0;
  31
  32   // Factory function; creates a new instance which is owned by the caller.
  33   // For normal usage, access the singleton via DBusThreadManager::Get().
  34   static AmplifierClient* Create();
  35
  36   // Calls Initialize method.
  37   // |callback| will be called with a DBusMethodCallStatus indicating whether
  38   // the DBus method call succeeded, and a bool that is the return value from
  39   // the DBus method.
  40   virtual void Initialize(const BoolDBusMethodCallback& callback) = 0;
  41
  42   // Calls SetStandbyMode method.
  43   // |callback| will be called with a DBusMethodCallStatus indicating whether
  44   // the DBus method call succeeded.
  45   virtual void SetStandbyMode(bool standby,
  46                               const VoidDBusMethodCallback& callback) = 0;
  47
  48   // Calls SetVolume method.
  49   // |callback| will be called with a DBusMethodCallStatus indicating whether
  50   // the DBus method call succeeded.
  51   virtual void SetVolume(double db_spl,
  52                          const VoidDBusMethodCallback& callback) = 0;
  53
  54  protected:
  55   // Create() should be used instead.
  56   AmplifierClient();
  57
  58  private:
  59   DISALLOW_COPY_AND_ASSIGN(AmplifierClient);
  60 };
  61
  62 }  // namespace chromeos
  63
  64 #endif  // CHROMEOS_DBUS_AMPLIFIER_CLIENT_H_