Context-sensitive F4 help

Question

Hello experts,
I have a normal ABAP report with a selection screen. On this screen I have two input fields, field_A and field_B. In field_A the user can choose from one of 4 pre-set values (A, B, C, D). Now, depending on this value choosen for field_A, the F4 help of field_B (and of course field_B's type) should change accordingly this selection in field_A.
So I have to questions:
1.) How to change an input field's type dynamically on a selection screen?
2.) How to set the F4 help of an input field dynamically on a selection screen?
Thanks in advance for your help!
Kind regards, Matthias

Answer 1

Hi,
Check below sample code where in material F4 is Dynamic based on the radio button selected i.e. deletion flag set or not.
Hope this is what you are expecting.
TABLES mara.
PARAMETERS: po_lvorm RADIOBUTTON GROUP g1 USER-COMMAND ucomm, "Deletion flagged
            po_nondl RADIOBUTTON GROUP g1 DEFAULT 'X'. "Deletion not flagged
SELECT-OPTIONS: so_matnr FOR mara-matnr.
TYPES: BEGIN OF t_mara,
         matnr TYPE mara-matnr,
       END OF t_mara.
DATA: i_mara TYPE STANDARD TABLE OF t_mara,
      i_rettab TYPE STANDARD TABLE OF ddshretval,
      wa_rettab TYPE ddshretval.
AT SELECTION-SCREEN ON VALUE-REQUEST FOR so_matnr-low.
  REFRESH i_mara[].
  IF po_lvorm EQ 'X'.
    SELECT matnr INTO TABLE i_mara FROM mara WHERE lvorm EQ 'X'.
  ELSE.
    SELECT matnr INTO TABLE i_mara FROM mara WHERE lvorm EQ space.
  ENDIF.
  CALL FUNCTION 'F4IF_INT_TABLE_VALUE_REQUEST'
    EXPORTING
  DDIC_STRUCTURE         = ' '
      retfield               = 'SO_MATNR-LOW'
  PVALKEY                = ' '
     dynpprog               = sy-repid
     dynpnr                 = sy-dynnr
  DYNPROFIELD            = ' '
  STEPL                  = 0
  WINDOW_TITLE           = WINDOW_TITLE
  VALUE                  = ' '
     value_org              = 'S'
  MULTIPLE_CHOICE        = ' '
  DISPLAY                = ' '
  CALLBACK_PROGRAM       = ' '
  CALLBACK_FORM          = ' '
  MARK_TAB               = MARK_TAB
IMPORTING
  USER_RESET             = USER_RESET
    TABLES
      value_tab              = i_mara
  FIELD_TAB              = FIELD_TAB
     return_tab             = i_rettab
  DYNPFLD_MAPPING        = DYNPFLD_MAPPING
   EXCEPTIONS
     parameter_error        = 1
     no_values_found        = 2
     OTHERS                 = 3
  IF sy-subrc <> 0.
MESSAGE ID SY-MSGID TYPE SY-MSGTY NUMBER SY-MSGNO
        WITH SY-MSGV1 SY-MSGV2 SY-MSGV3 SY-MSGV4.
  ENDIF.
  CLEAR wa_rettab.
  READ TABLE i_rettab INTO wa_rettab INDEX 1.
  IF sy-subrc IS INITIAL.
    MOVE wa_rettab-fieldval TO so_matnr-low.
  ENDIF.
AT SELECTION-SCREEN ON VALUE-REQUEST FOR so_matnr-high.
  IF po_lvorm EQ 'X'.
    SELECT matnr INTO TABLE i_mara FROM mara WHERE lvorm EQ 'X'.
  ELSE.
    SELECT matnr INTO TABLE i_mara FROM mara WHERE lvorm EQ space.
  ENDIF.
  CALL FUNCTION 'F4IF_INT_TABLE_VALUE_REQUEST'
  EXPORTING
  DDIC_STRUCTURE         = ' '
    retfield               = 'SO_MATNR-HIGH'
  PVALKEY                = ' '
    dynpprog               = sy-repid
    dynpnr                 = sy-dynnr
  DYNPROFIELD            = ' '
  STEPL                  = 0
  WINDOW_TITLE           = WINDOW_TITLE
  VALUE                  = ' '
    value_org              = 'S'
  MULTIPLE_CHOICE        = ' '
  DISPLAY                = ' '
  CALLBACK_PROGRAM       = ' '
  CALLBACK_FORM          = ' '
  MARK_TAB               = MARK_TAB
IMPORTING
  USER_RESET             = USER_RESET
  TABLES
    value_tab              = i_mara
  FIELD_TAB              = FIELD_TAB
     return_tab             = i_rettab
  DYNPFLD_MAPPING        = DYNPFLD_MAPPING
  EXCEPTIONS
    parameter_error        = 1
    no_values_found        = 2
    OTHERS                 = 3
  IF sy-subrc <> 0.
MESSAGE ID SY-MSGID TYPE SY-MSGTY NUMBER SY-MSGNO
        WITH SY-MSGV1 SY-MSGV2 SY-MSGV3 SY-MSGV4.
  ENDIF.
  CLEAR wa_rettab.
  READ TABLE i_rettab INTO wa_rettab INDEX 1.
  IF sy-subrc IS INITIAL.
    MOVE wa_rettab-fieldval TO so_matnr-high.
  ENDIF.
Thanks,
Vinod.