+\twocolitem{{\bf EVT\_SPLITTER\_SASH\_POS\_CHANGING(id, func)}}{The sash
+position is in the process of being changed. May be used to modify the
+position of the tracking bar to properly reflect the position that
+would be set if the drag were to be completed at this point. Processes
+a wxEVT\_COMMAND\_SPLITTER\_SASH\_POS\_CHANGING event.}