How to avoid flicker while handling WM_ERASEBKGND in Windows dialog

Question

I have a dialog that resizes. It also has a custom background which I paint in response to a WM_ERASEBKGND call (currently a simple call to FillSolidRect).

When t

Answer 1

Do nothing in the WM_ERASEBKGND handling and do the erase as part of your main WM_PAINT. You can either paint smarter so that you only redraw the invalid areas, or more easily, double-buffer the drawing.

By not doing anything in the erase background, you have all your drawing code in one location which should make it easier for others to follow and maintain.