chromeos/dbus/system_clock_client.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 CHROMEOS_DBUS_SYSTEM_CLOCK_CLIENT_H_
   6 #define CHROMEOS_DBUS_SYSTEM_CLOCK_CLIENT_H_
   7
   8 #include "base/callback.h"
   9 #include "chromeos/chromeos_export.h"
  10 #include "chromeos/dbus/dbus_client.h"
  11
  12 namespace chromeos {
  13
  14 // SystemClockClient is used to communicate with the system clock.
  15 class CHROMEOS_EXPORT SystemClockClient : public DBusClient {
  16  public:
  17   // Interface for observing changes from the system clock.
  18   class Observer {
  19    public:
  20     // Called when the status is updated.
  21     virtual void SystemClockUpdated();
  22
  23     // Called when the system clock has become settable or unsettable, e.g.,
  24     // when the clock syncs with or goes out of sync with the network.
  25     virtual void SystemClockCanSetTimeChanged(bool can_set_time);
  26
  27    protected:
  28     virtual ~Observer() {}
  29   };
  30
  31   ~SystemClockClient() override;
  32
  33   // Adds the given observer.
  34   virtual void AddObserver(Observer* observer) = 0;
  35   // Removes the given observer if this object has the observer.
  36   virtual void RemoveObserver(Observer* observer) = 0;
  37   // Returns true if this object has the given observer.
  38   virtual bool HasObserver(const Observer* observer) const = 0;
  39
  40   // Sets the system clock.
  41   virtual void SetTime(int64 time_in_seconds) = 0;
  42
  43   // Checks if the system time can be set.
  44   virtual bool CanSetTime() = 0;
  45
  46   // Creates the instance.
  47   static SystemClockClient* Create();
  48
  49  protected:
  50   // Create() should be used instead.
  51   SystemClockClient();
  52
  53  private:
  54   DISALLOW_COPY_AND_ASSIGN(SystemClockClient);
  55 };
  56
  57 }  // namespace chromeos
  58
  59 #endif  // CHROMEOS_DBUS_SYSTEM_CLOCK_CLIENT_H_