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  * Main idea behind the notify mediator is encapsulate

    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 generic

    40  * observer array implementation.

    41  *

    42  * @since 3.0

    43  */

    44 class MGenObserverNotifyMediatorBase

    45     {

    46     public:

    47 

    48         /**

    49          * Observer notification.

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

    51          */

    52         virtual void MediateNotifyL( TAny* aObserverToNotify ) = 0;

    53 

    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     protected:

    63 

    64         /**

    65          * Protected destructor.

    66          */

    67         virtual ~MGenObserverNotifyMediatorBase() {}

    68     };

    69 

    70 

    71 

    72 

    73 // CLASS DECLARATION

    74 /**

    75  * Generic observer array.

    76  *

    77  * Generic observer array to manage observers

    78  * and notify them. Observers are managed as

    79  * typeless TAny pointers. Notification is done

    80  * trough generic MGenObserverNotifyMediatorBase

    81  * notify mediator.

    82  *

    83  * @since 3.0

    84  */

    85 NONSHARABLE_CLASS( RGenericObserverArrayBase ) :

    86         private RPointerArrayBase   // CSI: 70 #

    87     {

    88 protected: //protected members for derived classes

    89 

    90     /**

    91      * C++ constructor.

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

    93      */

    94     RGenericObserverArrayBase();

    95 

    96     /**

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

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

    99      */

   100     void Close();

   101 

   102     /**

   103      * Adds observer.

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

   105      */

   106     TInt AddObserver( const TAny* aObserver );

   107 

   108     /**

   109      * Removes observer.

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

   111      */

   112     TInt RemoveObserver( const TAny* aObserver );

   113 

   114     /**

   115      * Gets observer count.

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

   117      */

   118     TInt Count();

   119 

   120     /**

   121      * Observer notify implementation.

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

   123      */

   124     void NotifyObservers( MGenObserverNotifyMediatorBase& aNotifyMediator );

   125 

   126 

   127     /**

   128      * Observer notify implementation.

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

   130      */

   131     void NotifyErrorObservers( MGenObserverNotifyMediatorBase& aNotifyMediator,

   132                                TInt aError );

   133 

   134     /**

   135      * Observer notify implementation.

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

   137      */

   138     TBool IsNotifyLoopRunning() const;

   139 

   140 

   141 private: //private helpers

   142 

   143     /**

   144      * Private helper.

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

   146      */

   147     void FinalizeObsArrayAfterNotifyLoop();

   148 

   149 

   150 private: //Data

   151 

   152     //OWN: Flag describing the observer array state

   153     TBool iNotifyLoopRunning;

   154     };

   155 

   156 #endif      //__RGenericObserverArrayBase_H__

   157 //  End of File

   158 

   159