/*

* Copyright (c) 2007 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:  Listens for changes to the call state*

*/

#ifndef CAMCALLSTATEAO_H

#define CAMCALLSTATEAO_H

//  INCLUDES

#include <e32property.h>

#include <ctsydomainpskeys.h>

// CONSTANTS

// MACROS

// DATA TYPES

// FUNCTION PROTOTYPES

// FORWARD DECLARATIONS

// CLASS DECLARATION

/**

*  

*  Mix-in class specifying the callback interface to be used with CCamCallStateAo

*

*  @since 3.0

*/

class MCamCallStateObserver

    {

    public:

        /**

        * Callback function, called when the call state changes

        * @since 3.0

        * @param aState The new call state

        * @param aError The error associated with request completion

        */    

        virtual void CallStateChanged( TPSCTsyCallState aState, TInt aError ) = 0;

    };

/**

*  Active Object class to watch the call state

*

*  @since 3.0

*/

class CCamCallStateAo : public CActive

    {

    public:  // Constructors and destructor        

        /**

        * Two-phased constructor.

        * @since 3.0

        * @param aObserver The observer requesting callback on call events

        * @return Constructed instance of the class

        */

        static CCamCallStateAo* NewL( MCamCallStateObserver* aObserver );

        /**

        * Destructor.

        */

        ~CCamCallStateAo();

    protected:  // Functions from base classes        

        /**

        * From CActive

        * Cancels an outstanding request

        * @since 3.0

        */

    	void DoCancel();		

        /**

        * From CActive

        * Called on completion of a request

        * @since 3.0

        */

    	void RunL();

        /**

        * From CActive

        * Called when an error occurs during a request

        * @since 3.0

        * @param aError The Epoc-error code for the error.

        * @return KErrNone

        */

    	TInt RunError( TInt aError );    	        

    private:

        /**

        * C++ default constructor.

        * @since 3.0

        * @param aObserver The observer requesting callback on call events

        */

        CCamCallStateAo( MCamCallStateObserver* aObserver );

        /**

        * By default Symbian 2nd phase constructor is private.

        */

        void ConstructL();

    public:     // Data

        // The observer to be notified on an event

        MCamCallStateObserver* iObserver;

        // Publish and Subscribe property handle

        RProperty iProperty;

    };

#endif      // CAMCALLSTATEAO_H

// End of File