In this case the SAP searchhelp is not
defined in the SAP data dictionary so that the techname= option
does not find a searchhelp name. Debugging the SAP application,
one can find out that SAP calls up the special function module "STEUER_TAXKM_HELP",
passing the value "MWST" as parameter "STEUERTAB_TATYP" .
You can implement the same solution in
GuiXT by defining your own ABAP exit program for the searchhelp
where you call up the SAP function module "STEUER_TAXKM_HELP".
Do it analogously to example 2 of the "InputField" keyword
documentation.
An alternative is to use a dropdown
field; either put a fixed value list into the script or read the
possible values dynamically from the SAP tables TSKM and TSKMT.