(Mac) Rollover Buttons in IB

Does anyone know the best way t开发者_如何转开发o create rollover buttons in IB? I tried a square button with image/alt image but nothing happens upon rollover.

There is an AMRollOverButton Project that comes with an Interface Builder pLugin. haven't tested it yet but have a look at it(at the section code): http://www.harmless.de/cocoa-code.php

if you're after what i believe you're after, then see:

 -[NSResponder mouseEntered:]
 -[NSResponder mouseExited:]

and family. on enter/exit, change the image (or do whatever changes you like).