[]   control   control_at   dirty!   draw_contents   draw_frame   draw_title   handle_click   height   hide!   new   on_submit   redraw   show!   width   x1   x2   y1   y2   yank_values  

dirty	->	dirty?
visible	->	visible?

controls	[RW]
dirty	[RW]
display	[RW]
handler	[RW]
title	[RW]
visible	[RW]
x1	[RW]
x2	[RW]
y1	[RW]
y2	[RW]