/*

* Copyright (c) 2006 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:   Observer interface definition for install operations

*

*/

#ifndef M_NCD_INSTALL_OPERATION_OBSERVER_H

#define M_NCD_INSTALL_OPERATION_OBSERVER_H

#include <e32cmn.h>

class MNcdInstallOperation;

class TNcdProgress;

class MNcdQuery;

/**

 *  Observer interface for install operations

 *

 *  Install operation users should implement this interface to be able to

 *  receive callbacks.

 *

 *  

 *  @see MNcdInstallOperation

 */

class MNcdInstallOperationObserver

    {

public:

    /**

     * Called when install has progressed. 

     *

     * @note This will be called only once per an installed file. 

     * The reason for this is that the install process is handled outside of

     * Catalogs Engine in the platform installer.

     *

     * 

     * @param aOperation The operation that sent the event.

     * @param aProgress Progress of the operation.

     */

    virtual void InstallProgress( MNcdInstallOperation& aOperation,

        TNcdProgress aProgress ) = 0;

    /**

     * Called when a query has been received for an operation.

     *

     * @note Querys need to be completed with MNcdOperation::CompleteQueryL()

     *       to continue the operation! Alternatively, the operation must be

     *       cancelled.

     * 

     * 

     * @see MNcdOperation

     * @see MNcdQuery

     * @param aOperation Uncounted reference to the operation that sent the event.

     * @param aQuery Pointer to the query that must be completed. Counted, Release()

     *        must be called after use.

     * @see MNcdOperation::CompleteQueryL()

     */

    virtual void QueryReceived( MNcdInstallOperation& aOperation,

        MNcdQuery* aQuery ) = 0;

    /**

     * Called when an operation has been completed.

     *

     * 

     * @param aOperation The operation that sent the event.

     * @param aError Error code for operation completion. 

     *               KErrNone for successful completion, KErrAbort if the user

     *               cancelled the operation, otherwise a system

     *               wide error code.

     */

    virtual void OperationComplete( MNcdInstallOperation& aOperation,

        TInt aError ) = 0;

protected:

    /**

     * Destructor

     *

     * An empty virtual destructor is implemented to prevent deletion 

     * of a class object through this interface.

     * Observer should not be deleted by the one that is observed.

     */

    virtual ~MNcdInstallOperationObserver() { }

    };

#endif //  M_NCD_INSTALL_OPERATION_OBSERVER_H