How to change controls simultaneously without repainting each one?

Question

For example I need to disable two buttons in runtime. After I disabled first button it bacame gray, the second - it also became gray. But I do not know how to make the repainting simultaneous!

I need something like that:

1. freeze the Form (disable repainting)
2. disable first button
3. disable second button
4. Enable Form repainting

How to implement that?

Answer 1

Look at the Win32 API WM_SETREDRAW message. For example:

SendMessage(Handle, WM_SETREDRAW, False, 0);
Button1.Enabled := False;
Button2.Enabled := False;
SendMessage(Handle, WM_SETREDRAW, True, 0);
InvalidateRect(Handle, nil, True);