monthly question about xcopyarea and expose events nd posting of the question that just doesn t seem to get answered suppose you have an idle app with a realized and mapped window that contains xlib graphics a button widget when pressed will cause a new item to be drawn in the window this action clearly should not call xcopyarea or equiv directly instead it should register the existence of the new item in a memory structure and let the same expose event handler that handles regular expose events e g window manager driven exposures take care of rendering the new image using an expose event handler is a proper way to do this because at the time the handler is called the xlib window is guaranteed to be mapped the problem of course is that no expose event is generated if the window is already visible and mapped what we need to do is somehow tickle the window so that the expose handler is hit with arguments that will enable it to render just the part of the window that contains the new item what is the best way to tickle a window to produce this behavior
