F4 help for PO number field with SELECT OPTIONS

Question

Hi all,
I have a field (PO no) using SELECT OPTIONS on my selection screen.I need F4 help for this field.How shud i declare it?
I have declared it as follows:
SELECTION-SCREEN BEGIN OF BLOCK b1 WITH FRAME TITLE text-001.
select-options sel_po for ZPO_LOI-zobject_id obligatory .
SELECTION-SCREEN END OF BLOCK b1.
ZPO_LOI is a table view with a z data element ZOBJECT_ID to which i have attached a search help which displays the required values for the PO field in the selection screen.But now the problem is i cant see the F4 icon for the field on the sel screen.
Please help.

Answer 1

Hi I have a sapmle code for this.
*&                AT SELECTION SCREEN ON VALUE REQUEST
*-- F4 help for IDOC numbers
AT SELECTION-SCREEN ON VALUE-REQUEST FOR s_docnum-low.
  PERFORM value_request_status USING 'S_DOCNUM-LOW'.
AT SELECTION-SCREEN ON VALUE-REQUEST FOR s_docnum-high.
  PERFORM value_request_status USING 'S_DOCNUM-HIGH'.
*&      Form  value_request_status
      text
     -->fp_field  dynpro field that gets the return value
FORM value_request_status  USING fp_field TYPE dynfnam.
  STATICS tl_values TYPE STANDARD TABLE OF tp_value.
  IF tl_values IS INITIAL.
     SELECT docnum FROM edidc UP TO 500 ROWS INTO TABLE tl_values
          WHERE credat   IN  s_credat
          AND   cretim   IN  s_cretim.
     IF sy-subrc eq 0.
        CALL FUNCTION 'F4IF_INT_TABLE_VALUE_REQUEST'
         EXPORTING
          retfield        = 'DOCNUM'
          dynpprog        = syst-repid
          dynpnr          = syst-dynnr
          dynprofield     = fp_field
          value_org       = 'S'
         TABLES
          value_tab       = tl_values
         EXCEPTIONS
          parameter_error = 1
          no_values_found = 2
         OTHERS          = 3.
         IF sy-subrc IS NOT INITIAL.
           MESSAGE i999(zz) WITH 'No values found'(004).
         ENDIF.
      ENDIF.
    ENDIF.
ENDFORM.                    " value_request_status
Regards,
Amit.