Datasource of autoform typeahead? Examples broken?

Is there a way to pass a template helper function as a datasource to an typeahead autoform field? I used sergeyt:typeahead before and it worked very fine. Now I’m switched to autoform and tried to use comerc:autoform-typeahead.

afFieldInput(name='' type="typeahead" data-source=cities)

cities is a Template Helper Method. With this I got a “TypeError: obj is undefined (jquery.js:391:3)”. I looked at the examples page but I got a lot of exceptions when I choosed typeahead.

Did you able to fix the issue?