/*

* Copyright (c) 2004 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 "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:  Declaration of CActiveFavouritesDbNotifier.

*

*/

#ifndef ACTIVE_FAVOURITES_DB_NOTIFIER_H

#define ACTIVE_FAVOURITES_DB_NOTIFIER_H

//  INCLUDES

#include <e32base.h>

#include <d32dbms.h>

// FORWARD DECLARATION

class RFavouritesDb;

class MFavouritesDbObserver;

// CLASS DECLARATION

/**

* ActiveFavouritesDbNotifier is an Active object encapsulating a favourites database notifier. 

* Once this notifier is Start()-ed, it keeps watching the database and notifies the

* observer, until the database is closed by all clients (i.e. released by

* DBMS), or it is DoCancel()-led.

*/

class CActiveFavouritesDbNotifier : public CActive

    {

    public:     // Constructor and destructor

        /**

        * Constructor.

        * @since 0.9 

        * @param aDb The favourites database to watch for.

        * @param aObserver The Observer to be notified about database events.

        */

        IMPORT_C CActiveFavouritesDbNotifier( RFavouritesDb& aDb, MFavouritesDbObserver& aObserver );

        /**

        * Destructor.

        */

        IMPORT_C virtual ~CActiveFavouritesDbNotifier();

    protected:  // from CActive

        /**

        * Invoked when the outstanding request completes.

        * @since 0.9

        * @return void 

        */

        IMPORT_C void RunL();

        /**

        * Cancel any outstading request. It's implementation of the Cancel protocol;

        * @since 0.9

        * @return void 

        */

        IMPORT_C void DoCancel();

    public:     // new methods

        /**

        * Start the notifier. The notification request is automatically

        * renewed until it is cancelled, or the database is closed by

        * all clients (i.e. released by DBMS).

        * @since 0.9

        * @return Error code.

        */

        IMPORT_C TInt Start();

    private:

        /**

        * Request database change notification from the Favourites Engine.

        * @since 0.9

        * @return void 

        */

        void NotifyChange();

    private:    // data

        RFavouritesDbNotifier iNotifier;    ///< Notifier object.

        RFavouritesDb& iDb;                 ///< Handle to the database.

        MFavouritesDbObserver* iObserver;   ///< Pointer to observer.

    };

#endif

// End of File