1 /*

     2 * Copyright (c) 2002-2006 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:  Provides way to notify events and register observers

    15 *                for events

    16 *

    17 */

    18 

    19 

    20 

    21 #ifndef TSATEVENTMEDIATOR_H

    22 #define TSATEVENTMEDIATOR_H

    23 

    24 //  INCLUDES

    25 #include <e32base.h>

    26 

    27 // FORWARD DECLARATIONS

    28 class MSatEventObserver;

    29 class TSatEventsObserver;

    30 

    31 // CLASS DECLARATION

    32 

    33 /**

    34 *  Provides way to notify events and register observers for events.

    35 *  Observers are not owned by this class and therefore observers are

    36 *  not deleted when TSatEventMediator instance is destroyed.

    37 *

    38 *  @lib SatEngine.dll

    39 *  @since Series 60 3.0

    40 */

    41 class TSatEventMediator

    42     {

    43     public:  // Constructors and destructor

    44 

    45         /**

    46         * C++ default constructor.

    47         */

    48         TSatEventMediator();

    49 

    50     public: // New functions

    51 

    52         /**

    53         * Notifies possible observers who are observing the event.

    54         * @param aEvent Integer identifying the event.

    55         * @return None

    56         */

    57         void Notify( TInt aEvent );

    58 

    59         /**

    60         * Registers observer for event. Same observer will not be added

    61         * more than once for one event.

    62         * @param aObserver Pointer of observer instance. Panic will occur if

    63         * aObserver is NULL.

    64         * @param aEvent Event, which will cause the notification of observer.

    65         * @return None

    66         */

    67         void RegisterL( MSatEventObserver* aObserver, TInt aEvent );

    68 

    69         /**

    70         * Unregisters the notification of single event.

    71         * @param aObserver Observer, whom event registeration will be

    72         * unregistered.

    73         * @param aEvent Event, which will be unregistered.

    74         * @return None

    75         */

    76         void Unregister( const MSatEventObserver* aObserver, TInt aEvent );

    77 

    78         /**

    79         * Unregisters the event observer.

    80         * @param aObserver Observer, whom event registeration will be

    81         * unregistered.

    82         */

    83         void Unregister( const MSatEventObserver* aObserver );

    84 

    85         /**

    86         * Resets the list of event observers. Used instead of destructor

    87         */

    88         void Reset();

    89 

    90     private:  // New functions

    91 

    92         /**

    93         * Checks if aObserver is already in the list of observers.

    94         * @param aObserver Observer that is checked from the list.

    95         * @return Pointer of the observer, where aObserver is registered.

    96         * Contains NULL pointer if aObserver is not already registered.

    97         */

    98         TSatEventsObserver* HasObserverInstance(

    99             const MSatEventObserver* aObserver ) const;

   100 

   101         /**

   102         * Deletes all observers marked as deleted during notify loop

   103         */

   104         void DeleteMarkedObservers();

   105 

   106     private:

   107 

   108         // Prohibit copy constructor if not deriving from CBase.

   109         TSatEventMediator( const TSatEventMediator& );

   110 

   111         // Prohibit assigment operator if not deriving from CBase.

   112         TSatEventMediator& operator=( const TSatEventMediator& );

   113 

   114     private:    // Data

   115 

   116         // event observers.

   117         RPointerArray<TSatEventsObserver> iEventsObservers;

   118 

   119         // Indicates are we notifying observers. If this flag is on,

   120         // observers cannot be removed from iEventsObservers. After

   121         // notify loop is done, observers can be replaced again

   122         TBool iIsNotifying;

   123 

   124         // Indicates are there any observers marked as deleted during

   125         // Notify loop

   126         TBool iDeletionsMarked;

   127     };

   128 

   129 #endif      // TSATEVENTMEDIATOR_H

   130 

   131 // End of File