/*

* 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:  An Active Object offering its request status for any

*                asynchronous request handling.

*

*/

#ifndef C_GENERICACTIVE_H

#define C_GENERICACTIVE_H

//  INCLUDES

#include <e32base.h>

class CGenericActive;

/**

 * The observer of CGenericActive's request events

 *

 * This class defines the interface to handle request events from CGenericActive.

 *

 * @since S60 v3.1

 */

class MGenericActiveObserver

    {

public:

    /**

     * Called by CGenericActive::RunL() to handle the request completion event.

     *

     * @since S60 v3.1

     * @param aActive the Active Object to which the request is assigned to.

     */

    virtual void RequestCompletedL(CGenericActive& aActive) = 0;

    /**

     * alled by CGenericActive::RunL() to handle the cancellation of an outstanding request.

     *

     * @since S60 v3.1

     * @param aActive the Active Object to which the request is assigned to.

     */

    virtual void CancelRequest(CGenericActive& aActive) = 0;

    /**

     * alled by CGenericActive::RunError() to handle an exception.

     *

     * @since S60 v3.1

     * @param aErr the leave code of RunL()

     */

    virtual TInt HandleRunError(TInt aErr) = 0;

    };

/**

 *

 * CGenericActive provides TRequestStatus for an async operation but it doesn't know the

 * detail of the request. CGenericActive could be used to implement timers, P&S subscribes 

 * that are "simple" enough operations. 

 *

 * @since S60 v3.1

 */

class CGenericActive : public CActive

    {

public:

    static CGenericActive* New(MGenericActiveObserver& aObserver, 

        CActive::TPriority aPriority, TInt aRequestId);

    static CGenericActive* NewL(MGenericActiveObserver& aObserver, 

        CActive::TPriority aPriority, TInt aRequestId);

    virtual ~CGenericActive();

public:

    /**

     * Calls SetActive().

     *

     * @since S60 v3.1

     */

    virtual void GoActive();

    /**

     * Gets the identifier of the request that this active object is serving.

     *

     * @since S60 v3.1

     * @return the request identifier

     */

    TInt RequestId() const;

    /**

     * Gets the identifier of the request that this active object is serving.

     *

     * @since S60 v3.1

     * @param the request identifier

     */

    void SetRequestId(TInt aRequestId);

    TRequestStatus& RequestStatus();

protected:

    /**

     * From CActive. 

     * cancels the outstanding request.

     *

     * @since S60 v3.1

     */

    virtual void DoCancel();

    /**

     * From CActive. 

     * Handles the request completion event.

     *

     * @since S60 v3.1

     */

    virtual void RunL();

    /**

     * From CActive. 

     * Handles the leave from RunL().

     *

     * @since S60 v3.1

     * @param aError the leave code in RunL()

     * @return the error code to Active Scheduler

     */

    virtual TInt RunError(TInt aError);

protected:

    CGenericActive(MGenericActiveObserver& aObserver, 

        CActive::TPriority aPriority, TInt aRequestId);

private:

    /**

     * The observer which is interested in the request handling events.

     * Not own.

     */

    MGenericActiveObserver& iObserver;

    /**

     * The request identifier assigned to this active object.

     */

    TInt iRequestId;

    };

#endif  // C_GENERICACTIVE_H