Try giving ref_tabname and ref_fieldname in field catalog:
WA_FIELDCAT-REF_TABNAME = 'MARA'.
WA_FIELDCAT-REF_FIELDNAME = 'MATNR'.
Also, check the following link:
http://scn.sap.com/thread/2058108
Regards
Try giving ref_tabname and ref_fieldname in field catalog:
WA_FIELDCAT-REF_TABNAME = 'MARA'.
WA_FIELDCAT-REF_FIELDNAME = 'MATNR'.
Also, check the following link:
http://scn.sap.com/thread/2058108
Regards