// Copyright (c) 2002-2009 Nokia Corporation and/or its subsidiary(-ies).

// All rights reserved.

// This component and the accompanying materials are made available

// under the terms of the License "Symbian Foundation License v1.0" to Symbian Foundation members and "Symbian Foundation End User License Agreement v1.0" to non-members

// which accompanies this distribution, and is available

// at the URL "http://www.symbianfoundation.org/legal/licencesv10.html".

//

// Initial Contributors:

// Nokia Corporation - initial contribution.

//

// Contributors:

//

// Description:

//

#ifndef __LOGVIEWCHANGEOBSERVER_H__

#define __LOGVIEWCHANGEOBSERVER_H__

// System includes

#include <logwrap.h>

/**

This class allows a client of the log engine to observe specific change events within

a given view.

@publishedAll 

@released

*/

class MLogViewChangeObserver

	{

public:

	/**Handle a change corresponding to a view addition

	This method is called when a log event is added to a view. The event maybe 

	recently added,	or have existed for some time but only now meet the 

	criteria of this view (i.e satisfy the filter) due to some other change.

	@param aId The id of the log event which has been added to the view.

	@param aViewIndex The position within the view at which the event has been 

	added.

	@param aChangeIndex	In a series of changes, this is the index of the 

	currently processing change. The change index will be greater than (or 

	equal to) 0, and less than the total change count.

	@param aTotalChangeCount This is the total count of all changes which will 

	be processed in this batch.

	 */

	virtual void HandleLogViewChangeEventAddedL(TLogId aId, TInt aViewIndex, TInt aChangeIndex, TInt aTotalChangeCount) = 0;

	/** Handle a change corresponding to a view change

	This method is called when a log event changes within a view.

	@param aId The id of the log event which has changed within the view.

	@param aViewIndex The position within the view where the change occurred.

	@param aChangeIndex	In a series of changes, this is the index of the 

	currently processing change. The change index will be greater than (or 

	equal to) 0, and less than the total change count.

	@param aTotalChangeCount This is the total count of all changes which will 

	be processed in this batch.

	 */

	virtual void HandleLogViewChangeEventChangedL(TLogId aId, TInt aViewIndex, TInt aChangeIndex, TInt aTotalChangeCount) = 0;

	/** Handle a change corresponding to a view deletion

	This method is called when a log event is removed from a view.

	@param aId The id of the log event which has been removed from the view

	@param aViewIndex The position within the view which the event previously 

	held.

	@param aChangeIndex In a series of changes, this is the index of the 

	currently processing change. The change index will be greater than (or 

	equal to) 0, and less than the total change count.

	@param aTotalChangeCount This is the total count of all changes which 

	will be processed in this batch

	 */

	virtual void HandleLogViewChangeEventDeletedL(TLogId aId, TInt aViewIndex, TInt aChangeIndex, TInt aTotalChangeCount) = 0;

	};

#endif