/*

* 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:  This is the observer class for the Device Diagnostics 

*                Application's Engine class.  It is used to propagate engine 

*                events to UI elements.

*

*/

#ifndef DEVDIAGENGINEOBSERVER_H

#define DEVDIAGENGINEOBSERVER_H

/**

 *  The observer class for the application engine.

 *

 *  This class is an abstract interface which is used by the application

 *  engine to pass events from itself and the diagnostics framework to the UI

 *  components.

 */

class MDevDiagEngineObserver

    {

public: // Data Types

    /**  An enum which identifies different engine events. */

    enum TAppEngineCommand

        {

        EDevDiagEngineCommandPluginLoadProgress,

        EDevDiagEngineCommandPluginLoadComplete,

        EDevDiagEngineCommandRunTimeReqs,

        EDevDiagEngineCommandTestExecutionBegin,

        EDevDiagEngineCommandProgressDataUpdated,

        EDevDiagEngineCommandResultsDataUpdated,

        EDevDiagEngineCommandSinglePluginExecutionDone,

        EDevDiagEngineCommandGroupExecutionDone,

        EDevDiagEngineCommandGroupExecutionProgress,

        EDevDiagEngineCommandTestExecutionSuspended,

        EDevDiagEngineCommandTestExecutionCancelled,

        EDevDiagEngineCommandTestExecutionResumed,

        EDevDiagEngineCommandObserverChanged,

        EDevDiagEngineCommandGetLastResults,

        EDevDiagEngineCommandViewSwitch,

        EDevDiagEngineCommandExecutionStopping

        };

public: // Pure Virtual Functions

    /**

     * The observer interface to inform of engine events.

     *

     * @param aCommand The engine event.

     * @param aError Any error code related to the event.

     * @param aCustom Any data related to the event.  Ownership is not

     *                transferred.  The format of the data is determined by

     *                the event type.

     */

    virtual void HandleEngineCommandL( TAppEngineCommand aCommand,

                                       TInt aError,

                                       TAny* aCustom ) = 0;

    };

#endif // DEVDIAGENGINEOBSERVER_H