Sounds like a Checkbox.

i was attracted by the collapse capability of lists, but a checkbox if probably much more suited for my needs.

you can add a group and move your checkbox to that group and you get the same effect. Have a look at the ControlP5group example.

 you can add a group and move your checkbox to that group and you get the same effect. Have a look at the ControlP5group example.

Thanks for the hint. In the meanwhile i've made some test with toggle+group and i've got almost what i need. The only shortcoming with this approach is the absence of a scroll bar, so if i add, let's say, 5 toggles and their total heigh is greater than the group one they are drawn outside. A list can store an arbitrary number of items in a fixed space. But i can live with this solution.

Thanks!