How to make a window "autoresize" after it was shown?

Hi,

I'm dynamically attaching and detaching labels in one AG_Window (the
window would uglily expand if I only hid the labels) but they run out
of the window space (because the window is automatically sized without
the labels when shown).

Is there a way to have the window automatically resized as if it was
shown for the first time again?

Best regards,
Jakob