QT button with a picture that can be grayed out?

[Zorgoth]

I am making a GUI in QT. This is my second QT project; my first was a simple 2D graphing program. I am very new to it and the grapher was made a long time ago so I forgot a lot since then. For now I want to be able to make a square button with a picture of my choice on top of it and with the option to "grey it out" when necessary so it can't be pressed. How can I do that?

[daasdingo]

use a QToolButton to get a square button
and use setEnabled(bool) to grey it out

[Zorgoth]

Thanks!