How to get dynamic colors to work on button

Hi,
I've got a simple question. From the Energy Demo project in Zenon 6.51. The buttons at the bottom bar changes its background color when its clicked on. Then, the background color changes back when other buttons are clicked. However i cant seem to figure out how to do that on my own project.
From that demo, I can only figure out the following steps:

create a boolean internal variable (internal-button_status). change the limit color.
create two write set value functions(on & off) for internal-button_status.
link the on function to limit[1] and off function to limit[2]
create a button. link the colors dynamic>background color to internal-button_status

If i run the runtime only with the steps above, the runtime will hang as it goes into an inifinite loop because of the functions linked in limit[1] and limit[2].
Can you guys point out what other steps am i missing out?
Please advise.
Best regards,
Justin

This is a migrated post! Originally posted on 06.06.2012 by user jjplaw. Please be aware that information can be outdated.