/*

* Copyright (c) 2007-2008 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:  Class header for CWsfWlanInfoSortingDbChangeNotifier

*

*/

#ifndef C_WSFWLANINFOSORTINGDBCHANGENOTIFIER_H

#define C_WSFWLANINFOSORTINGDBCHANGENOTIFIER_H

//  EXTERNAL INCLUDES

#include <e32base.h>

#include <d32dbms.h>

//  FORWARD DECLARATIONS

class MWsfWlanInfoSortingFilterVisitor;

/**

 * Active object to monitor changes in a given database

 *

 * @lib wsfwlaninfosorting.lib

 * @since S60 5.0

 */

NONSHARABLE_CLASS( CWsfWlanInfoSortingDbChangeNotifier ): public CActive

    {

    public:     // construction

        /**

         * Factory function.

         * @since S60 5.0

         * @param aDatabase The database to be monitored. Ownership not passed.

         * @return Class instance

         */

        static CWsfWlanInfoSortingDbChangeNotifier* NewLC( 

                                                      RDbDatabase& aDatabase );

        /**

         * Factory function.

         * @since S60 5.0

         * @param aDatabase The database to be monitored. Ownership not passed.

         * @return Class instance

         */

        static CWsfWlanInfoSortingDbChangeNotifier* NewL( 

                                                      RDbDatabase& aDatabase );

        ~CWsfWlanInfoSortingDbChangeNotifier();

    private:    // constructors

        /**

         * Constructor

         * @since S60 5.0

         * @param aDatabase The database to be monitored. Ownership not passed.

         */

        CWsfWlanInfoSortingDbChangeNotifier( RDbDatabase& aDatabase );

        void ConstructL();    

    public:     // new methods

        /**

        * Starts monitoring the database

        * @since S60 5.0

        */

         void StartDbObservation();

         /**

         * Append filter to the list of clients to be notified. 

        * @since S60 5.0

         * @param aRelatedFilter A filter which is interested in db events.

         *                       Ownership not passed.

         * @return - void

         */

        void AppendDbRelatedFilterL( 

                            MWsfWlanInfoSortingFilterVisitor* aRelatedFilter );

        /**

        * Removes the filter from the list of clients. 

        * @since S60 5.0

         * @param aRelatedFilter A filter which is interested in db events.

         *                       Ownership not passed.

         * @return - void

         */

        void RemoveDbRelatedFilter( 

                            MWsfWlanInfoSortingFilterVisitor* aRelatedFilter );

    private: // from CActive

        void DoCancel(); 

        void RunL();

    private: //data    

        /**

        * The database to be monitored. Not owned.

        */

        RDbDatabase* iDatabase;

        /**

        * Database notifier

        */

        RDbNotifier iNotifier;

        /**

        * Array of DB-related filters to be notified

        */

        RPointerArray<MWsfWlanInfoSortingFilterVisitor> iDbAwareFilters;

    };

#endif // C_WSFWLANINFOSORTINGDBCHANGENOTIFIER_H