/*

* 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:  The base class for listening to events in Publish & Subscribe or in

* 				Central Repository

*

*/

#ifndef CPROENGOBSERVERBASE_H

#define CPROENGOBSERVERBASE_H

// INCLUDES

#include <e32base.h>

// CLASS DECLARATION

/**

* The base class for listening to events in Publish & Subscribe or in

* Central Repository. This is a helper class for CProEngNotifyHandlerImpl.

*

*  @lib ProfileEngine.lib

*  @since 3.1

*/

NONSHARABLE_CLASS( CProEngObserverBase ) : public CActive

    {

    protected:  // constructor and destructor

        CProEngObserverBase( TUint32 aKey );

        virtual ~CProEngObserverBase() {};

    public: // New functions:

        /**

         * Absract method to request notifications from the source determined

         * by the subclass. This must be called once after the real observer

         * class is constructed. After that this is called by RunL() of this

         * class.

         * @return KErrNone if succeed, otherwise a system-wide error code.

         */

        virtual TInt RequestNotification() = 0;

        /**

         * Abstract method to send notification to the observer.

         */

        virtual void NotifyObserverL() = 0;

        /**

         * Abstract method to send notification about the given error to the

         * observer.

         * @param aError the error code to be delivered to the observer.

         */

        virtual void NotifyError( TInt aError ) = 0;

    private: // Functions from base classes

        /**

         * From CActive.

         */

        void RunL();

    protected: // Data:

        // The key to observe

        TUint32 iKey;

    };

#endif      //  CPROENGOBSERVERBASE_H

// End of File