[VW7] Newbie question: resetting a widget's focus

Hi,

I have a main window with some action buttons and a sub-canvas that
consists of a text editor and a list box. The application model for
the sub-canvas responds to the #losingFocus event for the text editor
via the method, #exit.

My quandary is this:

In the #exit method I have a conditional, following which, if true,
the focus is to be returned to the edit box otherwise focus is given
to a parent window button.

I just can not see a way of returning focus to the edit box in the
sub-canvas. I've tried just about everything but to no avail. Can
anyone help me?

Regards, John Trinder