method to repaint a window?

I'm havving a problem if leave my Window idle for an hour and then I try to re-Show() a hidden window it pops up but the window is not updating correctly. I noticed if i resize the window it will start updating the window correctly. Is there anything that does the equivalent of the what the resize does as far as forcing the GUI to updates is events. Somethign like a window force of a repaint. Or maybe som开发者_开发知识库ething that forces an update event. I tried Window.Active, Focus, but nothing is working. Thank you.

You can invalidate the window which will force a redraw.