diff -r 89d6a7a84779 -r 25a17d01db0c Symbian3/PDK/Source/GUID-BE65B3A7-04E8-5406-B46A-09E2608E0F1F.dita --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/Symbian3/PDK/Source/GUID-BE65B3A7-04E8-5406-B46A-09E2608E0F1F.dita Fri Jan 22 18:26:19 2010 +0000 @@ -0,0 +1,95 @@ + + + + + +Requesting +Log Engine Notifications This tutorial describes how to request notification from Log Engine. +

The Log Engine +records events so that other applications can react to them in ways which +are not part of its own specification. A typical reaction to an event might +be refreshing the screen of the device or causing it to beep, but that is +not Log Engine functionality. The Log Engine notifies other applications of +a change to its database. It provides two interfaces which you implement to +set up notification of changes:

    +

  • MLogClientChangeObserver

    • +

  • MLogViewChangeObserver

    • +
 + +Implement MLogClientChangeObserver + MLogClientChangeObserver concerns changes which +are global to the database and it has a single member function to be implemented: + +Implement HandleLogClientChangeEventL of MLogClientChangeObserver +Its arguments are: +
    +

  • TUid aChangeType +the UID of the type of event which occurred

    • +

  • TInt aChangeParameter1

    • +

  • TInt aChangeParameter2

    • +

  • TInt aChangeParameter3

    • +
 +The last three arguments are context-specific: their meaning is specific +to the type of event that occurred. + + + + +Implement MLogViewChangeObserver + MLogViewChangeObserver concerns changes which are +specific to a database view and it has three member functions to be implemented: + + +HandleLogViewChangeEventAddedL + + +HandleLogViewChangeEventChangedL + + +HandleLogViewChangeEventDeletedL + + +Each of them has the same arguments: + + +TLogId aId + + +TInt aViewIndex + + +TInt aChangeIndex + + +TInt aTotalChangeCount + + + + +

A change to a view typically occurs as part of a sequence of changes, +and the position of the change event record in the view typically reflects +this +fact. +

The argument aId is the Id of the log event in the database. +The argument aViewIndex is the position in the view +where the event record was added, changed or deleted. The argument +aChangeIndex is the index of the event in the sequence of +changes. The argument aTotalChangeCount is the total number +of events in the sequence of changes +

 + +Maintaining +Log Events +Setting Up +A Log Engine Client +Displaying +Log Events +Configuring +Log Engine + \ No newline at end of file