/*

* Copyright (c) 2006-2007 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:   Interface to extend bio control functionality

*

*/

#ifndef MSGBIOCONTROLEXTENSION_H

#define MSGBIOCONTROLEXTENSION_H

/**

 * Bio control extension interface ids.

 *

 * @see MMsgBioControlExtension::BioControlExtension

 */

enum TMsgBioControlExtensions

    {

    // Add new enum tag for a new extension. To maintain BC always add new

    // tags only to the end of existing tags and do not touch existing tags,

    // even if extensions are deprecated. Link the enum tags to types using

    // Doxygen comments.

    /**

     * Extension interface id for MMsgBioControlScrollExtension.

     */

    KMsgBioControlScrollExtension = 1

    };

/**

 * Interface for Bio control extension.

 *

 * @since 3.2

 */

class MMsgBioControlExtension

    {

    public:

    /**

     * Extension point for future BIO control extension interfaces.

     * @since 3.2

     * @param aExtensionId The identifier for the requested extension interface.

     *                     See TMsgBioControlExtensions.

     * @return Untyped pointer to the extension interface.

     *         The pointer must be cast to appropriate type.

     */

    virtual TAny* BioControlExtension( TInt aExtensionId ) = 0;

    };

/**

 * Interface for scrolling extension

 *

 * @since 3.2

 */

class MMsgBioControlScrollExtension

    {

    public:

    /**

     * Performs the internal scrolling of control if needed.

     * @since 3.2     

     * @param aPixelsToScroll Amount of pixels to scroll.

     * @param aDirection      Scrolling direction.

     * @return Amount of pixels that were scrolled. Zero value means the component

     * cannot be scrolled to that direction anymore and view should be moved.

     */

    virtual TInt ExtScrollL( TInt aPixelsToScroll, TMsgScrollDirection aDirection ) = 0;

    /**

     * Prepares control for viewing.

     * @since 3.2     

     * @param aEvent	The event type

     * @param aParam Event related parameters

     */

    virtual void ExtNotifyViewEvent( TMsgViewEvent aEvent, TInt aParam ) = 0;

    };

#endif // MSGBIOCONTROLEXTENSION_H