为选择屏幕的字段设置F4帮助

在没有参考 数据元素，域和搜索帮助的情况下，自定义F4 帮助

1，PARAMETERS: p_bukrs(4) TYPE C MATCHCODE OBJECT H_T001.

2，AT SELECTION-SCREEN  ON VALUE-REQUEST  FOR  p_bukrs.

PERFORM frm_f4 CHANGING p_bukrs.

FORM frm_f4 CHANGING p_value.

CONSTANTS cns_retfield TYPE fieldname VALUE 'BUKRS'.

DATA: BEGIN OF lt_value OCCURS 0,
            bukrs LIKE t001-bukrs, "公司代码

butxt LIKE t001-butxt, " 公司名称

END OF lt_value. 
   DATA: lt_retuen LIKE TABLE OF  ddshretval WITH HEADER LINE.

SELECT bukrs butxt FROM t001 INTO TABLE lt_value.

CALL FUNCTION 'F4IF_INT_TABLE_VALUE_REQUEST'

EXPORTING
        retfield        = cns_retfield

value_org       = 'S'

TABLES
       value_tab       = lt_value

return_tab      = lt_retuen

EXCEPTIONS
       parameter_error = 1

no_values_found = 2

OTHERS          = 3.

IF sy-subrc = 0.
    READ TABLE lt_retuen  INDEX 1.

p_value  = lt_retuen-fieldval.

ELSE.

ENDIF.
ENDFORM.                    "frm_f4_bukrs