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".
8 // Initial Contributors:
9 // Nokia Corporation - initial contribution.
14 // Client observer class
22 EXPORT_C TInt RDbNotifier::Open(RDbDatabase& aDatabase)
23 /** Opens a DBMS change notifier on a database.
25 Note that a notifier cannot be opened on a client side database.
27 @param aDatabase The database to be observed.
28 @return KErrNone if successful, otherwise another of the system-wide error
31 TRAPD(r,iNotifier=aDatabase.iDatabase->NotifierL());
35 EXPORT_C void RDbNotifier::Close()
36 /** Closes a DBMS change notifier. Any outstanding notification request is automatically
39 Note that this function can be called on a DBMS change notifier that has already
45 LOCAL_C void Notify(RDbHandle<CDbNotifier>& aNotifier,TRequestStatus& aStatus,CDbNotifier::TType aType)
47 aNotifier->Notify(aType,aStatus);
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.
54 When a database event occurs, the request completes and the TRequestStatus
55 objectcontains one of the enumerators defined by the TEvent enumeration member.
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.
60 Only one notification request can be outstanding on this notifier at any one
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()
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. */
72 ::Notify(iNotifier,aStatus,CDbNotifier::EUnlock);
75 EXPORT_C void RDbNotifier::NotifyChange(TRequestStatus& aStatus)
76 /** Makes an asynchronous request for notification of changes to the database.
78 All events which indicate a change to the database are reported; in practice,
79 this means all database events except RDbNotifier::EUnlock.
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
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.
88 Only one notification request can be outstanding on this notifier at any one
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()
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. */
100 ::Notify(iNotifier,aStatus,CDbNotifier::EChange);
103 EXPORT_C void RDbNotifier::Cancel()
104 /** Cancels any outstanding notification request to this DBMS notifier.
106 The outstanding request completes with a KErrCancel. */