Clearing AR Invoice Form - C# code EPICOR 9.05

Hi all! 

In the AR Invoice Form, at Actions>Group>Post will post the invoice group.

Under button click, written set of code to do this process.

It is posting the invoice group and clearing the list of invoices from the grid. However, not clearing  the AR Invoice Form (InvcGrp data) after posting.

Tried oTrans.Clear(), oTrans.ClearDatasets(), oTrans.Refresh,oTrans.NotifyAll()

anyway to clear the form??