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 ASH_SESSION_SESSION_STATE_OBSERVER_H_ 6#define ASH_SESSION_SESSION_STATE_OBSERVER_H_ 7 8#include <string> 9 10#include "ash/ash_export.h" 11#include "ash/session/session_state_delegate.h" 12#include "base/basictypes.h" 13 14namespace ash { 15 16class ASH_EXPORT SessionStateObserver { 17 public: 18 // Called when active user has changed. 19 virtual void ActiveUserChanged(const std::string& user_id) {} 20 21 // Called when another user gets added to the existing session. 22 virtual void UserAddedToSession(const std::string& user_id) {} 23 24 // Called when session state is changed. 25 virtual void SessionStateChanged(SessionStateDelegate::SessionState state) {} 26 27 protected: 28 virtual ~SessionStateObserver() {} 29}; 30 31// A class to attach / detach an object as a session state observer with a 32// scoped pointer. 33class ASH_EXPORT ScopedSessionStateObserver { 34 public: 35 explicit ScopedSessionStateObserver(ash::SessionStateObserver* observer); 36 virtual ~ScopedSessionStateObserver(); 37 38 private: 39 ash::SessionStateObserver* observer_; 40 41 DISALLOW_COPY_AND_ASSIGN(ScopedSessionStateObserver); 42}; 43 44} // namespace ash 45 46#endif // ASH_SESSION_SESSION_STATE_OBSERVER_H_ 47