SAP/ABAP: LISTBOX, Selection Screen

PARAMETERS : p_dep(30) AS LISTBOX VISIBLE LENGTH 30.


*----------------------------------------------------------------------*
*     AT SELECTION-SCREEN
*----------------------------------------------------------------------*
AT SELECTION-SCREEN OUTPUT.

  IF gt_departman[] IS INITIAL.
    SELECT a~zdepartman b~ltext FROM zmmt_departman AS a
      INNER JOIN zmmt_departmant AS b ON a~zdepartman = b~zdepartman
      INTO CORRESPONDING FIELDS OF TABLE gt_departman
      WHERE b~spras = sy-langu
        .
    name = 'P_DEP'.
    LOOP AT gt_departman.
      value-key = gt_departman-zdepartman.
      value-text = gt_departman-ltext.
      APPEND value TO list.
    ENDLOOP.
    CALL FUNCTION 'VRM_SET_VALUES'
      EXPORTING
        id     = name
        values = list.
  ENDIF.