1 /*

     2 * Copyright (c) 2004 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:  Generic observer array.

    15 *

    16 */

    17 

    18 #ifndef __RGENERICOBSERVERARRAYBASE_H

    19 #define __RGENERICOBSERVERARRAYBASE_H

    20 

    21 //  INCLUDES

    22 #include <E32Base.h>

    23 

    24 

    25 

    26 // CLASS DECLARATION

    27 /**

    28  * Observer notify mediator base.

    29  *

    30  * Base interface to manage observer notifications

    31  * and notify errors. Typical implementation will

    32  * forward notifications to actual type specific

    33  * mediator.

    34  *

    35  *

    36  * the observer array management from actual observer

    37  * type specific details. (Type specific details will

    38  * be implemented by the concrete mediator.) Usage

    39  * of mediator base interface allows geneic

    40  * observer array implementation.

    41  *

    42  * @since 2.1

    43  */

    44 

    45 NONSHARABLE_CLASS( MGenObserverNotifyMediatorBase )

    46     {

    47 public:

    48 

    49     /**

    50      * Observer notification.

    51      * This member is internal and not intended for use.

    52      */

    53     virtual void MediateNotifyL( TAny* aObserverToNotify, TAny* aNotifyData ) = 0;

    54 

    55     /**

    56      * Observer notification from error.

    57      * This member is internal and not intended for use.

    58      */

    59     virtual void MediateNotifyError( TAny* aObserverToNotify, TInt aLeaveError ) = 0;

    60 

    61 

    62     /**

    63      * Observer notification from error.

    64      * This member is internal and not intended for use.

    65      */

    66     virtual void MediateError( TAny* aObserverToNotify, TInt aError ) = 0;

    67 

    68 

    69 protected:

    70 

    71     /**

    72      * Protected destructor.

    73      */

    74     virtual ~MGenObserverNotifyMediatorBase() {}

    75     };

    76 

    77 

    78 

    79 

    80 // CLASS DECLARATION

    81 /**

    82  * Generic observer array.

    83  *

    84  * Generic observer array to manage observers

    85  * and notify them. Observers are managed as

    86  * typeless TAny pointers. Notification is done

    87  * trough generic MGenObserverNotifyMediatorBase

    88  * notify mediator.

    89  *

    90  * @since 2.1

    91  */

    92 NONSHARABLE_CLASS( RGenericObserverArrayBase ) : private RPointerArrayBase

    93     {

    94 protected: //protected members for derived classes

    95 

    96     /**

    97      * C++ constructor.

    98      * This member is internal and not intended for use.

    99      */

   100     RGenericObserverArrayBase();

   101 

   102     /**

   103      * Closes the array and frees all memory allocated to it.

   104      * This member is internal and not intended for use.

   105      */

   106     void Close();

   107 

   108     /**

   109      * Adds observer.

   110      * This member is internal and not intended for use.

   111      */

   112     TInt AddObserver( const TAny* aObserver );

   113 

   114     /**

   115      * Removes observer.

   116      * This member is internal and not intended for use.

   117      */

   118     TInt RemoveObserver( const TAny* aObserver );

   119 

   120     /**

   121      * Gets observer count.

   122      * This member is internal and not intended for use.

   123      */

   124     TInt Count();

   125 

   126     /**

   127      * Observer notify implementation.

   128      * This member is internal and not intended for use.

   129      */

   130     void NotifyObservers( MGenObserverNotifyMediatorBase& aNotifyMediator,

   131                           TAny* aNotifyData );

   132 

   133     /**

   134      * Observer notify implementation.

   135      * This member is internal and not intended for use.

   136      */

   137     void NotifyObserversFromError( MGenObserverNotifyMediatorBase& aNotifyMediator,

   138                                    TInt aError );

   139 

   140 private: //private helpers

   141 

   142     /**

   143      * Private helper.

   144      * This member is internal and not intended for use.

   145      */

   146     void FinalizeObsArrayAfterNotifyLoop();

   147 

   148 

   149 private: //Data

   150     ///< Flag describing the observer array state, owned

   151     TBool iNotifyLoopRunning;

   152     };

   153 

   154 #endif      //__RGENERICOBSERVERARRAYBASE_H

   155 //  End of File

   156 

   157