/*
* Copyright (c) 2009 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:  Publish & Subscribe property change observer
*
*/

#ifndef CIMALERTPROPERTYOBSERVER_H
#define CIMALERTPROPERTYOBSERVER_H

//  INCLUDES
#include <e32base.h>        // CActive
#include <e32property.h>    // RProperty

#include "mimalertpropertynotificationobserver.h"


// CLASS DECLARATION

/**
*  Implementation of the Publish & Subscribe property change observer
*
*  @lib MGXMediaFileAPI.lib
*  @since 2.6
*/
NONSHARABLE_CLASS(CIMAlertPropertyObserver) : public CActive
    {
    public:  // Constructors and destructor

        /**
        * Two-phased constructor.
        * @param aObserver Observer to be informed when observed 
        *                  property changes
        */
        static CIMAlertPropertyObserver* NewL( 
                MIMAlertPropertyNotificationObserver& aObserver );

        /**
        * Destructor.
        */
        virtual ~CIMAlertPropertyObserver();

    public:     // New functions

        /**
        * Starts observing the given key for any changes
        * Notifies the observer when the property changes
        * @since 2.6
        * @param aCategory, Category of the observed property
        * @param aKey, Observed property
        */
        void ObservePropertyChangeL( TUid aCategory, TUint aKey );

        /**
        * Stops observing the key given with call ObserverPropertyChangeL
        */
        void CancelObserve( );

        /**
        * Gets the uid this observer is observing
        * @return the category
        */
        TUid Category();

        /**
        * Gets the uid this observer is observing
        * @return the key
        */
        TUint Key();


    protected:  // Functions from base classes

        /**
        * From CActive
        */
        void RunL();

        /**
        * From CActive
        */
        void DoCancel();

    private:

        /**
        * C++ default constructor.
        */
        CIMAlertPropertyObserver( MIMAlertPropertyNotificationObserver& aObserver );


    private:    // Data

        // Owns: Observed property
        RProperty iProperty;

        // Observer to be informed when property changes
        MIMAlertPropertyNotificationObserver& iObserver;

		// the category this observer is attached to
		TUid iCategory;
		// the key this observer is attached to
		TUint iKey;

    };

#endif      // CIMALERTPROPERTYOBSERVER_H

// End of File