paperUI not discovering channels


i installed openhab2.2 in ubuntu 16.04 (virtual machine).
i connected some homematic components with homegear and homematic-lan-gateway (HM-CFG-LAN), added things with paperUI and all channels listed in paperUI.
everything works fine.

now i want to define the “things” instead of paperUI in config files.
my config-file: /etc/openhab2/things/homematic.things:

Bridge homematic:bridge:875efcfb [ gatewayAddress="localhost" ]
  Thing HM-CC-RT-DN OEQ1718341 "BZ_HK" @ "BUEZ"

paperUI is showing the thing with state ONLINE:


but no channels are listed.

what’s the cause?