Redraw Problems please help

OK i have a mixer app that has 36 meters drawing on the screen at once. I’m blitting two images for each meter so it only redraws whats changed and not the entire image. problem is if another application window goes over my app and then i remove it the mixer app redraws and the bottom halves of my meters disappear. is there a event or some technique i can use to figure out when i need to draw a full meter when this happens??

please have mercy on a helpless Noob

You need to only invalidate the bits that change - i.e. call repaint (x, y, w, h) for only the bits that change, but your paint() routine must alway draw everything that needs drawing.

That totaly makes sense i’m such a dork

Thanks for your help.