HOW TO AVOID DUPLICATES WHILE USING VRM FM

Question

HI EXPERTS,
                  I AM USING VRM FM TO PASS VALUES INTO LISTBOX IN SCREENS.FIRST TIME IT IS WORKING PROPERLY WHEN I USE IT FOR THE SECOND TIME IT IS SHOWING THE PREVIOUS DATAS ENTRIES ALSO .HOW TO DELETE THE DUPLICATE ENTRIES OF IT .
THIS IS MY CODE.
when 'ENTER'.
      select POSNR ARKTX from LIPS into corresponding fields of table i_pstyp WHERE VBELN EQ VBELN.
      LOOP AT I_PSTYP .
        W_DDLIST-KEY = I_PSTYP-POSNR.
        W_DDLIST-TEXT = I_PSTYP-POSNR.
APPEND W_DDLIST TO POSNR1.
CLEAR W_DDLIST.
CALL FUNCTION 'VRM_SET_VALUES'
        EXPORTING
          ID              = 'POSNR'
          VALUES          = POSNR1.
IN THIS IF I SELECT NEXT VBELN WITHOUT EXITING FROM THE SCREEN THE PREVIOUS VBELN'S LINE ITEMS ALSO ARE DISPLAYING .WHAT SHALL I DO .
MANI

Answer 1

when 'ENTER'.
select POSNR ARKTX from LIPS
       into corresponding fields of table i_pstyp
       WHERE VBELN EQ VBELN.
LOOP AT I_PSTYP .
W_DDLIST-KEY = I_PSTYP-POSNR.
W_DDLIST-TEXT = I_PSTYP-POSNR.
APPEND W_DDLIST TO POSNR1.
CLEAR W_DDLIST.
ENDLOOP. " Endloop here. the FM should not be called inside the loop
CALL FUNCTION 'VRM_SET_VALUES'
EXPORTING
ID = 'POSNR' " hope you are using the fieldname correctly
VALUES = POSNR1.
CLEAR : POSNR1. " this will stop repeating the values in your drop down list
Regards
Gopi