1 /*

     2 * Copyright (c) 2007-2009 Nokia Corporation and/or its subsidiary(-ies). 

     3 * All rights reserved.

     4 * This component and the accompanying materials are made available

     5 * under the terms of "Eclipse Public License v1.0"

     6 * which accompanies this distribution, and is available

     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - initial contribution.

    11 *

    12 * Contributors:

    13 *

    14 * Description:  Field event queue interface

    15 *

    16 */

    17 

    18 

    19 #ifndef MESMRFIELDEVENTQUEUE_H

    20 #define MESMRFIELDEVENTQUEUE_H

    21 

    22 class MESMRFieldEvent;

    23 class MESMRFieldEventObserver;

    24 

    25 /**

    26  *  MESMRFieldEventQueue defines an iterface for field event queue.

    27  *  It provides event queue for CESMRField to send events to its

    28  *  event observers. The interface provides both synchronous and

    29  *  asynchrounous event notification methods.

    30  */

    31 class MESMRFieldEventQueue

    32     {

    33 

    34 public:

    35     

    36     /**

    37      * Adds observer to the event queue.

    38      *

    39      * @param aObserver the observer.

    40      */

    41     virtual void AddObserverL( MESMRFieldEventObserver* aObserver ) = 0;

    42     

    43     /**

    44      * Removes observer from the event queue.

    45      *

    46      * @param aObserver the observer.

    47      */

    48     virtual void RemoveObserver( MESMRFieldEventObserver* aObserver ) = 0;

    49     

    50     /**

    51      * Notifies event to the event observers in the queue.

    52      * Event is notified synchronously.

    53      * 

    54      * @param aEvent the event.

    55      */

    56     virtual void NotifyEventL( const MESMRFieldEvent& aEvent ) = 0;

    57 

    58     /**

    59      * Enques event to event queue and notifies it asynchronously to

    60      * the observers. Ownership of the event is transferred to the queue.

    61      * 

    62      * @param aEvent the event to enque to the event queue.

    63      */

    64     virtual void NotifyEventAsyncL( MESMRFieldEvent* aEvent ) = 0;

    65     

    66     /**

    67      * Removes event from the event queue.

    68      * 

    69      * @param aEvent the event to remove from the event queue.

    70      */

    71     virtual void CancelEvent( MESMRFieldEvent* aEvent ) = 0;

    72     

    73 protected:

    74 

    75     virtual ~MESMRFieldEventQueue() {}

    76 

    77     };

    78 

    79 #endif // MESMRFIELDEVENTQUEUE_H