1 // Copyright (c) 1998-2009 Nokia Corporation and/or its subsidiary(-ies).

     2 // All rights reserved.

     3 // This component and the accompanying materials are made available

     4 // under the terms of "Eclipse Public License v1.0"

     5 // which accompanies this distribution, and is available

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

     7 //

     8 // Initial Contributors:

     9 // Nokia Corporation - initial contribution.

    10 //

    11 // Contributors:

    12 //

    13 // Description:

    14 // Client observer class

    15 // 

    16 //

    17 

    18 #include "UD_STD.H"

    19 

    20 // Class RDbNotifier

    21 

    22 EXPORT_C TInt RDbNotifier::Open(RDbDatabase& aDatabase)

    23 /** Opens a DBMS change notifier on a database.

    24 

    25 Note that a notifier cannot be opened on a client side database.

    26 

    27 @param aDatabase The database to be observed.

    28 @return KErrNone if successful, otherwise another of the system-wide error 

    29 codes. */

    30 	{

    31 	TRAPD(r,iNotifier=aDatabase.iDatabase->NotifierL());

    32 	return r;

    33 	}

    34  

    35 EXPORT_C void RDbNotifier::Close()

    36 /** Closes a DBMS change notifier. Any outstanding notification request is automatically 

    37 cancelled.

    38 

    39 Note that this function can be called on a DBMS change notifier that has already 

    40 been closed. */

    41 	{

    42 	iNotifier.Close();

    43 	}

    44 

    45 LOCAL_C void Notify(RDbHandle<CDbNotifier>& aNotifier,TRequestStatus& aStatus,CDbNotifier::TType aType)

    46 	{

    47 	aNotifier->Notify(aType,aStatus);

    48 	}

    49 

    50 EXPORT_C void RDbNotifier::NotifyUnlock(TRequestStatus& aStatus)

    51 /** Makes an asynchronous request for notification of a database event. All events, 

    52 including the release of all read locks, are reported.

    53 

    54 When a database event occurs, the request completes and the TRequestStatus 

    55 objectcontains one of the enumerators defined by the TEvent enumeration member.

    56 

    57 Alternatively, if an outstanding request is cancelled by a call to the Cancel() 

    58 member function of this class, then the request completes with KErrCancel.

    59 

    60 Only one notification request can be outstanding on this notifier at any one 

    61 time.

    62 

    63 Note that if further database events occur while a client is handling a request 

    64 completion, the notifier records the most significant database event and this 

    65 is signalled as soon as the client issues the next NotifyUnlock() or NotifyChange() 

    66 request.

    67 

    68 @param aStatus The request status object. If the request is cancelled, this 

    69 is set to KErrCancel. If the request completes normally, this is set to one 

    70 of the enumerator values defined by the TEvent enumeration member. */

    71 	{

    72 	::Notify(iNotifier,aStatus,CDbNotifier::EUnlock);

    73 	}

    74 

    75 EXPORT_C void RDbNotifier::NotifyChange(TRequestStatus& aStatus)

    76 /** Makes an asynchronous request for notification of changes to the database.

    77 

    78 All events which indicate a change to the database are reported; in practice, 

    79 this means all database events except RDbNotifier::EUnlock.

    80 

    81 When a change event occurs, the request completes and the TRequestStatus object 

    82 contains one of the appropriate enumerators defined by the TEvent enumeration 

    83 member.

    84 

    85 Alternatively, if an outstanding request is cancelled by a call to the Cancel() 

    86 member function of this class, then the request completes with KErrCancel.

    87 

    88 Only one notification request can be outstanding on this notifier at any one 

    89 time.

    90 

    91 Note that if further database events occur while a client is handling a request 

    92 completion, the notifier records the most significant database event and this 

    93 is signalled as soon as the client issues the next NotifyUnlock() or NotifyChange() 

    94 request.

    95 

    96 @param aStatus The request status object. If the request is cancelled, this 

    97 is set to KErrCancel. If the request completes normally, this is set to one 

    98 of the enumerator values defined by the TEvent enumeration member. */

    99 	{

   100 	::Notify(iNotifier,aStatus,CDbNotifier::EChange);

   101 	}

   102 

   103 EXPORT_C void RDbNotifier::Cancel()

   104 /** Cancels any outstanding notification request to this DBMS notifier.

   105 

   106 The outstanding request completes with a KErrCancel. */

   107 	{

   108 	iNotifier->Cancel();

   109 	}