Echelon OpenLNS - Manual (Page 1001)

OpenLNS Programmer's Reference 964
ILcaMsgMonitorPointListener
The ILcaMsgMonitorPointListener interface can be added to a COM object created in a
multi-threaded programming environment such as Visual C++. You must then call the
Advise method of the MsgMonitorPoint with the object that implements this interface as an
argument. This will allow the object to receive updates from that message monitor point
directly, rather than through the Object Server. The following table summarizes the
ILcaMsgMonitorPointListener interface .
Description Allows a COM object implementing this
interface to directly receive updates from a
message monitor point.
Added to API LNS Release 3.0.
Methods • UpdateErrorEvent
• UpdateEvent
Methods
The ILcaMsgMonitorPointListener interface contains the following methods :
• UpdateErrorEvent
• UpdateEvent
UpdateErrorEvent
Summary Allows an object to execute a callback for message monitor
point and network variable update errors. This can only be
used in multi-threading programming environments such as
Visual C++. It cannot be used in Visual Basic . To create an
object to receive UpdateErrorEvent updates, follow these
steps:
1. Create an object that implements the
ILcaMsgMonitorPointListener interface.
2. Define the object's behavior when the UpdateErrorEvent
method is called.
3. Call the Advise method of the MsgMonitorPoint object
with the object created in step 1 as the object element.
OpenLNS will then provide event notification of update
errors for the selected monitor point using callbacks
instead of Windows messaging.
You must call the Advise method from the event handler
that is handling the update error events for the message
monitor point. For more information on this, see the
Advise method of the MsgMonitorPoint object.
The object created in step 1 will now call this method
whenever a message monitor point error is received.
Availability Local and full clients.