DDLB in model node attribute

Hi All!

What generates the drop down list box input help for a model attribute? There is no get_v method generated for the attribute, but in the screen there is a DDLB.

For example in the 'ApptSQ' view of the 'BT126S_APPT' component for the 'Struct.Process_Type' attribute of the 'BTQACT' model node there is no 'get_v' method generated, but if I call this screen in the WEB Client somehow a DDLB is generated.

The problem is that there is no value in this drop down list box.

Please help, where the search help is genereated for this attribute?

Thank you very much.

Regards,

Attila