/*

* 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 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: 

*       Interface class declaration for Phonebook contact database observers.

*

*/

#ifndef __MPbkContactDbObserver_H__

#define __MPbkContactDbObserver_H__

//  INCLUDES

#include <cntdef.h>     // cntdbobs.h requires TContactItemId from this header

#include <cntdbobs.h>   // MContactDbObserver

// FORWARD DECLARATIONS

class CPbkContactEngine;

// CLASS DECLARATION

/**

 * Interface class for Phonebook contact database observers.

 *

 * @see MContactDbObserver

 * @see CPbkContactChangeNotifier

 */

class MPbkContactDbObserver : public MContactDbObserver

    {

    protected:  // Derived class interface

        /**

         * Called by CPbkContactEngine when it receives a database 

         * change event. From MContactDbObserver.

		 * @param aEvent The database event.

         */

        virtual void HandleDatabaseEventL(TContactDbObserverEvent aEvent) = 0;

        /**

         * Called by CPbkContactEngine after HandleDatabaseEventL has been 

         * called for all observers.

         * In other words: CPbkContactEngine calls first HandleDatabaseEventL

         * for all its observers and then this function again for all 

         * observers. You can think of it as an "all observers have seen 

         * aEvent" -notification. This used in Phonebook view activation for 

         * now. Default implementation does nothing.

         *

         * @param aEvent The database event

         */

        virtual void DatabaseEventHandledL(TContactDbObserverEvent /*aEvent*/)

            {

            // Empty default implementation

            }

        /**

         * Protected destructor. 

         * Observers are not destroyed via this interface.

         */

        virtual ~MPbkContactDbObserver() { }

    private:  // friend declarations

        /// CPbkContactEngine calls protected functions of this class.

        friend class CPbkContactEngine;

    };

#endif // __MPbkContactDbObserver_H__

// End of File