bar changing colour, and a subwindow gaining the keyboard focus.
An application is activated or deactivated when one of its frames becomes activated,
-or a frame becomes inactivated resulting in all application frames being inactive. (Windows only)
+or a frame becomes inactivated resulting in all application frames being inactive.
Please note that usually you should call \helpref{event.Skip()}{wxeventskip} in
your handlers for these events as not doing so can result in strange effects.