code: def _getMethodsVoc(self):
          
          methods = api.search({
              "portal_type": "Method",
              "is_active": True
          }, "bika_setup_catalog")
  
          items = map(lambda m: (api.get_uid(m), api.get_title(m)), methods)
          items.sort(lambda x, y: cmp(x[1], y[1]))
          items.insert(0, ("", _("Not specified")))
  
          return DisplayList(list(items))
docs: Return the registered methods as DisplayList