I've got a widget that gets displayed by calling QWidget->showFullScreen(). This works fine for this widget, it takes up the whole screen and has no border. I then have another widget that calls the same... the new widget is borderless (which is proper), but only takes up a small portion of the screen and I can see the previous widget under the new widget.

The layout for the new widget should tell it to expand to fill up the screen, but this appears to be failing. I then have yet another widget that tries to go full-screen on top of the previous widgets, and that suffers the same symptoms. Is there a limit to telling widgets to go full-screen?

I'm writing an app that is supposed to really be the only application a machine will run, under an ultra-simple window manager (or perhaps directly under X).

I'm using Qt 4.2.3 under X11R7