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:
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
TUid
aChangeType
the UID of the type of event which occurred
TInt aChangeParameter1
TInt aChangeParameter2
TInt aChangeParameter3
MLogViewChangeObserver
MLogViewChangeObserver
concerns changes which are
specific to a database view and it has three member functions to be implemented:
Each of them has the same arguments:
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