ui/views/win/windows_session_change_observer.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 UI_VIEWS_WIN_WINDOWS_SESSION_CHANGE_OBSERVER_H_
   6 #define UI_VIEWS_WIN_WINDOWS_SESSION_CHANGE_OBSERVER_H_
   7
   8 #include <windows.h>
   9
  10 #include "base/callback.h"
  11 #include "base/macros.h"
  12
  13 namespace views {
  14
  15 // Calls the provided callback on WM_WTSSESSION_CHANGE messages along with
  16 // managing the tricky business of observing a singleton object.
  17 class WindowsSessionChangeObserver {
  18  public:
  19   typedef base::Callback<void(WPARAM)> WtsCallback;
  20   explicit WindowsSessionChangeObserver(const WtsCallback& callback);
  21   ~WindowsSessionChangeObserver();
  22
  23  private:
  24   class WtsRegistrationNotificationManager;
  25
  26   void OnSessionChange(WPARAM wparam);
  27   void ClearCallback();
  28
  29   WtsCallback callback_;
  30
  31   DISALLOW_COPY_AND_ASSIGN(WindowsSessionChangeObserver);
  32 };
  33
  34 }  // namespace views
  35
  36 #endif  // UI_VIEWS_WIN_WINDOWS_SESSION_CHANGE_OBSERVER_H_