to catch item select event in List Box

I have a list box on my custom page. I need to select on of the item from that List Box and on that select event I need to do some other procedure. So I want to know how to catch that item select event. Can any one please tell me how to do this in NSIS??????

Thanks

Did you see the included example testnotify.nsi?

Retrieving the state of the control which accepts the notify flag is the way to go.