/*

* Copyright (c) 2005 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:  Listener for Publish and subscribe data.

*

*/

#ifndef GSPUBSUBSLISTENER_H

#define GSPUBSUBSLISTENER_H

//  INCLUDES

#include <e32base.h>

#include <e32std.h>

#include <e32property.h>

// FORWARD DECLARATIONS

class MGSSettingPSObserver;

// CLASS DECLARATION

/**

*  RProperty poller.

*

*  @lib gs.lib

*  @since Series 60 3.0

*/

NONSHARABLE_CLASS( CGSPubSubsListener ) : public CActive

    {

    public:  // Constructors and destructor

        /**

        * Two-phased constructor.

        * @param aUid the Uid to use

        * @param aKey item's key

        * @param aObserver callback interface for notification

        * @return instance of CGSPubSubsListener

        */

        static CGSPubSubsListener* NewL( const TUid aUid, const TInt aKey, 

                                         MGSSettingPSObserver* aObserver );

        /**

        * Destructor.

        */

        virtual ~CGSPubSubsListener();

    public: // New functions.

        /**

        * Gets integer value from P & S.

        * @param aVal a value in return

        * @return error code

        */       

        TInt Get( TInt& aVal );

        /**

        * Gets 8 bit string value from P&S.

        * @param aVal a value in return

        * @return error code

        */

        TInt Get( TDes8& aVal );

        /**

        * Gets 16 bit descriptor value from P&S.

        * @param aVal a value in return

        * @return error code

        */

        TInt Get( TDes16& aVal );

    private: // From CActive.

        /** @see CActive::RunL */

        virtual void RunL();

        /** @see CActive::Cancel */

        virtual void DoCancel();

        /** @see CActive::RunError */

        virtual TInt RunError( TInt aError );

        /**

        * Starts the listening (RunL).

        */

        void StartListening();

    private:

        /**

        * C++ default constructor.

        * @param aUid the Uid to use

        * @param aKey item's key

        * @param aObserver callback interface for notification

        */

        CGSPubSubsListener( const TUid aUid,  TInt aKey, 

                            MGSSettingPSObserver* aObserver );

        /**

        * By default Symbian 2nd phase constructor is private.

        */

        void ConstructL();

    private:    // Data

        // UID of the monitored item.

        TUid        iUid;

        // ID of the monitored item.

        TInt        iId;

        // Property to subscribe to.

        RProperty   iProperty;

        // The notification interface.

        MGSSettingPSObserver* iCallback;

    };

#endif // GSPUBSUBSLISTENER_H

// End of File