Error showing exception column

Question

Hi,
I get the following error message trying to generate an exeption column:
Field "USAGE" is unknown.
I have the following sample code:
REPORT  zdktesticon.
TYPE-POOLS: icon.
TYPES: BEGIN OF t_sflight.
        INCLUDE STRUCTURE sflight.
TYPES: seatsfree TYPE sflight-seatsocc,
exception
usage TYPE n,
END OF t_sflight.
Internal table
DATA: it_sflight TYPE TABLE OF t_sflight.
Workarea for data fetch
DATA: wa_sflight LIKE LINE OF it_sflight.
Reference for ALV instance
DATA: gr_alv TYPE REF TO cl_salv_table.
DATA: lr_columns
TYPE REF TO cl_salv_columns_table.
DATA: lr_column
TYPE REF TO cl_salv_column_table.
START-OF-SELECTION.
retrieve data into internal table
  SELECT * FROM sflight
  INTO CORRESPONDING FIELDS OF TABLE it_sflight.
fill additional data fields
  LOOP AT it_sflight INTO wa_sflight.
seats free
    wa_sflight-seatsfree = wa_sflight-seatsmax + wa_sflight-seatsmax_b
                          + wa_sflight-seatsmax_f
                          - wa_sflight-seatsocc - wa_sflight-seatsocc_b
                          - wa_sflight-seatsocc_f.
usage (exception light)
    IF wa_sflight-seatsfree = 0.
      wa_sflight-usage = '1'.
    ELSEIF wa_sflight-seatsfree <= 20.
      wa_sflight-usage = '2'.
    ELSE.
      wa_sflight-usage = '3'.
    ENDIF.
    MODIFY it_sflight
      FROM wa_sflight
      TRANSPORTING
        seatsfree
        usage.
  ENDLOOP.
TRY.
  CALL METHOD cl_salv_table=>factory
    IMPORTING
      r_salv_table = gr_alv
    CHANGING
      t_table      = it_sflight.
   CATCH cx_salv_msg.
ENDTRY.
get columns object
  lr_columns = gr_alv->get_columns( ).
  lr_columns->set_exception_column(
value = ’usage’
GROUP = SPACE
CONDENSED = IF_SALV_C_BOOL_SAP=>FALSE
END-OF-SELECTION.
What am I missing?
Regards
Morten

Answer 1

Hi,
Declare one data value A type lvc_fname value 'USAGE'.
and pass to the method.
Reward if useful!