/*

* Copyright (c) 2006-2006 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:  Header file for preset change notifier

*

*/

#ifndef C_CVRPRESETCHANGENOTIFIER_H

#define C_CVRPRESETCHANGENOTIFIER_H

#include <e32base.h>

class MPSPresetObserver;

class RPSServNotifier;

class RPSServ;

/**

 * Preset change notifier.

 *

 * Notifies the observer whenever any changes are done to the preset database.

 */

NONSHARABLE_CLASS( CPSPresetNotifier ) : public CActive

    {

public:

    /**

     * Two-phased constructor.

     *

     * The notifier is automatically set active after creation.

     * 

     * @param   aServ       Preset server session.

     * @param   aObserver   The observer to notify.

     * @return  The newly created object.

     */

    IMPORT_C static CPSPresetNotifier* NewL( RPSServ& aServ, MPSPresetObserver& aObserver );

    /**

     * Destructor.

     */

    IMPORT_C ~CPSPresetNotifier();

public:

    /**

     * Two-phased constructor.

     * Used only internally.

     *

     * The notifier is automatically set active after creation.

     * 

     * @param   aServ       Preset server session.

     * @param   aObserver   The observer to notify.

     * @param   aId         The ID of the preset to observe, or <code>KErrNotFound</code>

     *                      if all changes should result in a notification.

     * @return  The newly created object.

     */

    static CPSPresetNotifier* NewL( RPSServ& aServ, MPSPresetObserver& aObserver, TInt aId );

private:

    /**

     * Constructor.

     *     

     * @param   aServ       Preset server session.

     * @param   aObserver   The observer to notify.

     * @param	aPriority   Priority of the active object.

     */

    CPSPresetNotifier( RPSServ& aServ, MPSPresetObserver& aObserver, TInt aPriority );

    /**

     * Second-phase constructor.

     *

     * @param   aId         The ID of the preset to observe, or <code>KErrNotFound</code>

     *                      if all changes should result in a notification.

     */

    void ConstructL( TInt aId );

    /**

     * Static notify call back that is used after a failed notification.

     *

     * This will request a new notification to be received.

     *

     * @param   aSelf       Pointer to self.

     * @return  <code>KErrNone</code>.

     */

    static TInt StaticDelayedNotifyCallBack( TAny* aSelf );

// from base class CActive

    void DoCancel();

    void RunL();

    TInt RunError( TInt aError );

private:

    /** Timer that is used to request a notify after one has been failed. */

    CPeriodic* iTimer;

    /** Preset server session. */

    RPSServ& iServ;

    /** The observer to notify when presets change. */

    MPSPresetObserver& iObserver;

    /** Internal notifier implementation. */

    RPSServNotifier* iNotifier;

    /** Extension. */

    TAny* iExtension;

    };

#endif // C_CVRPRESETCHANGENOTIFIER_H