Dynamically changing wxTextCtrl from wxTE_MULTILINE to non-multiline

hello.
 
i used wxDesigner 2.10c (Red Hat Linux 9.0) to create a frame.  inside which is a wxBoxSizer that contains a wxTextCtrl.  i want to be able to change the wxTextCtrl to single or multi line depending on the user's needs.  i tried designing the frame using a single-line version of wxTextCtrl, then changing the wxTE_MULTILINE bit using SetWindowStyleFlag after the frame has been created, however this caused many errors to appear on the console.
 
so, is there a way to change single / multi line mode after the frame has been created?  or is there a work around that would give the same result?
 
thank you for your help,
Dean