/*

* Copyright (c) 2002 Nokia Corporation and/or its subsidiary(-ies). 

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of "Eclipse Public License v1.0"

* which accompanies this distribution, and is available

* at the URL "http://www.eclipse.org/legal/epl-v10.html".

*

* Initial Contributors:

* Nokia Corporation - initial contribution.

*

* Contributors:

*

* Description: 

*    This is the definition for CDosEvent class.

*

*/

#ifndef __DOSEVENT_H__

#define __DOSEVENT_H__

#include "doseventrcvservice.h"

class CDosEventRcvService;

class CDosWaitingEvent;

/**

* It represents an event type that has at least one listener. It forms part of a list of

* of events that is checked by the EventManager when an event arrives to the DosServer.

* It maintains a list of listeners wishing to receive the type of event.

*/

NONSHARABLE_CLASS( CDosEvent ) : public CBase

{

public:

	/**

	* Constructor.

	*/

	inline CDosEvent();

	/**

	* Destructor.

	*/

	~CDosEvent();

	/**

	* NewL function that creates the object.

	* @param aEvent Unique Id of the event.

	* @return A pinter to the newly created object.

	*/

	static CDosEvent* NewL(TUint aEvent);

	/**

	* The function compares two events. It's used to maintain an order in the Event array owned by 

	* CEventManagerBase.

	* @param aFirst One event.

	* @param aSecond The other event.

	* @return -1 if first < second, 1 if first > second or 0 if equal.

	*/

	static TInt Compare(const CDosEvent& aFirst,const CDosEvent& aSecond);

	/**

	* Returns the event Id.

	* @return Event Id.

	*/

	inline TUint Event() const;

	/**

	* Returns the number of listeners registered to this event.

	* @return Number of listeners.

	*/

	inline TInt ListenerCount() const;

	/**

	* Adds a listener to the event's list.

	* @param aListener A pointer to the listener to be added.

	*/

	void AddListener(CDosEventRcvService* aListener);

	/**

	* Removes a listener from the event's list.

	* @param aListener A pointer to the listener to be removed.

	*/

	void RemoveListener(CDosEventRcvService* aListener);

	/**

	* It delivers an event to all the listeners in the event's list.

	* @param aEvent A pointer to the event.

	*/

	void InformListeners(CDosWaitingEvent* aEvent);

private:

	/**

	* Symbian two-phased constructor.

	* @param aEvent Unique Id of the event type.

	*/

	void ConstructL(TUint aEvent);

	/**

	* It tells if a certain listener is registered for this event type.

	* @param aListener A pointer to the listener to be checked.

	* @return ETrue if the listener is on the list, EFalse otherwise.

	*/

	TBool ListenerRegistered(CDosEventRcvService* aListener);

private:

	//A list of clients listening to this event type.

	TSglQue<CDosEventRcvService> iListenerList; 

	//Use to browser trough the iListenerList.

    TSglQueIter<CDosEventRcvService> iListenerIter;

	//Id of the event.

	TUint iEventName;

	//Number of listeners in the list.

	TInt iListenerCount;

};

#include "dosevent.inl"

#endif // __DOSEVENT_H__