-Sets the new sash position. Set to -1 from the event handler code to prevent
-the sash from repositioning.
+In the case of wxEVT\_COMMAND\_SPLITTER\_SASH\_POS\_CHANGED events,
+sets the the new sash position. In the case of
+wxEVT\_COMMAND\_SPLITTER\_SASH\_POS\_CHANGING events, sets the new
+tracking bar position so visual feedback during dragging will
+represent that change that will actually take place. Set to -1 from
+the event handler code to prevent repositioning.