#IupFill Example in LED 
#Uses the Fill element to horizontally centralize a button and to justify it to the left and right.

caixae = FRAME [TITLE="Left"]   (HBOX(BUTTON ("Ok", acao_ok), FILL()))
caixac = FRAME [TITLE="Middle"] (HBOX(FILL(), BUTTON ("Ok", acao_ok), FILL()))
caixad = FRAME [TITLE="Right"]  (HBOX(FILL(), BUTTON ("Ok", acao_ok)))
filld	= DIALOG [TITLE="IupFill",SIZE=120]
(VBOX(caixae, caixac, caixad) )