ThisDatabaseDocument object
ThisDatabaseDocument addresses the active Base document whose properties can be read and set, and whose methods can be called.
ThisDatabaseDocument returns an object of type com.sun.star.sdb.XOfficeDatabaseDocument.
ThisDatabaseDocumentWhen the active window does not relate to a Base document, ThisDatabaseDocument returns Nothing.
When the active window is the Basic IDE, ThisDatabaseDocument object returns the database owning the current script.
Opening current database "formName" and maximizing it can be achieved as shown:
Dim form As Object
ThisDatabaseDocument.CurrentController.connect("","")
form = ThisDatabaseDocument.FormDocuments.getByName("formName").open )
form.currentController.frame.ContainerWindow.IsMaximized = True