Pie segment change listener not called

I am trying to listen changes in pie chart segment selections. I am adding the listener like so:

piesegment.addChangeListener { changedSegment in
    print("changed selection \(changedSegment.isSelected)")
 } 

The closure is never called however. My first question is: Is this the right way of doing this? In Android I implement the PieSegmentChangeListener interface and do an addIsSelectedChangeListener on the segment. In ios the SCIPieSegmentChangeListener is not a protocol. My second question is: How can I create a my own listener like in android and add it to the segment?

By the way support should not be exired!!!!