That's it. I need to create a ButtonGroup that allows to select a option or, if the user click on the selected option, deselect the item (nothing will be selected) and, of course, capture the event to do something.
Just in case Jeff's link is broken in the future, here's what's described: you need to subclass ButtonGroup to allow a no-selection, and add your buttons to this buttongroup.
public class NoneSelectedButtonGroup extends ButtonGroup {
@Override
public void setSelected(ButtonModel model, boolean selected) {
if (selected) {
super.setSelected(model, selected);
} else {
clearSelection();
}
}
}