How to create function code for field in GRID like list box in screen

Question

Hi all,
I have requirement like drop down is created for field1 in GRID,
and have given f4 help for it, as soon as i change the data in the field
event has to trigger to update thevalues in other field.
This scenario i worked on screens where field is created with listbox and assign function code to it
when the field value changes the event  triggers .
Is there is anything like that which will fire the event for field value changes.
can i update anything  through the  fieldcatalogue.
anybody help me on this
Regards,
Madhavi

Answer 1

Hi Madhavi,
yes we can do that by registering edit events..
check the below example.. has both the variants dropdown/f4 hlp...
screen flow logic
PROCESS BEFORE OUTPUT.
  MODULE pbo.
PROCESS AFTER INPUT.
  MODULE pai AT EXIT-COMMAND.
program
*       CLASS lcl_event_responder DEFINITION                           *
CLASS lcl_event_responder DEFINITION.
  PUBLIC SECTION.
    DATA  : ls_changed_cell TYPE  lvc_s_modi,
            lv_language     TYPE  spras..
    METHODS refresh_changed_data  FOR EVENT data_changed
                                  OF cl_gui_alv_grid
                                  IMPORTING er_data_changed
                                            e_ucomm.
ENDCLASS.                    "event_responder DEFINITION
DATA: go_handler         TYPE REF TO lcl_event_responder,
      go_container       TYPE REF TO cl_gui_custom_container,
      go_grid            TYPE REF TO cl_gui_alv_grid,
      gt_fieldcat        TYPE lvc_t_fcat,
      gv_language        TYPE spras VALUE 'E',
      gt_outtab          TYPE TABLE OF makt WITH HEADER LINE.
PARAMETERS : dropdown TYPE char01 RADIOBUTTON GROUP grp,
             f4help   TYPE char01 RADIOBUTTON GROUP grp.
START-OF-SELECTION.
  CALL SCREEN 100.
END-OF-SELECTION.
*       MODULE PBO OUTPUT                                             *
MODULE pbo OUTPUT.
  SET PF-STATUS 'BASIC'.
  PERFORM create_and_init_alv CHANGING gt_outtab[]
                                       gt_fieldcat.
ENDMODULE.                    "pbo OUTPUT
*       MODULE PAI INPUT                                              *
MODULE pai INPUT.
  SET SCREEN 0. LEAVE SCREEN.
ENDMODULE.                    "pai INPUT
FORM create_and_init_alv CHANGING pt_outtab LIKE gt_outtab[]
                                  pt_fieldcat TYPE lvc_t_fcat.
  CHECK go_container IS NOT BOUND.
  CREATE OBJECT go_container
    EXPORTING
      container_name = 'CUSTOM'.
  CREATE OBJECT go_grid
    EXPORTING
      i_parent = go_container.
  PERFORM build_display_table.
  PERFORM build_fieldcat CHANGING pt_fieldcat.
  IF dropdown EQ abap_true.
    PERFORM set_drdn_table.
  ENDIF.
  go_grid->set_table_for_first_display( CHANGING  it_fieldcatalog      = pt_fieldcat
                                                  it_outtab            = pt_outtab ).
  go_grid->set_ready_for_input( 1 ).
" raises the 'data_changed' event when we select another cell/any action after changing the data
  go_grid->register_edit_event( EXPORTING i_event_id = cl_gui_alv_grid=>mc_evt_modified ).
  CREATE OBJECT go_handler.
  SET HANDLER go_handler->refresh_changed_data FOR go_grid.
ENDFORM.                               "CREATE_AND_INIT_ALV
FORM build_display_table.
  FREE gt_outtab.
  SELECT * FROM makt UP TO 20 ROWS INTO TABLE gt_outtab WHERE spras EQ gv_language.
ENDFORM.                               "build_display_table
FORM build_fieldcat CHANGING pt_fieldcat TYPE lvc_t_fcat.
  DATA ls_fcat TYPE lvc_s_fcat.
  CALL FUNCTION 'LVC_FIELDCATALOG_MERGE'
    EXPORTING
      i_structure_name = 'MAKT'
    CHANGING
      ct_fieldcat      = pt_fieldcat.
  LOOP AT pt_fieldcat INTO ls_fcat.
    IF    ls_fcat-fieldname EQ 'SPRAS'.
      ls_fcat-edit       = abap_true..
      ls_fcat-outputlen  = 8.
      IF dropdown EQ abap_true.
        ls_fcat-drdn_hndl  = '1'.
        ls_fcat-checktable = '!'.        "do not check foreign keys
      ENDIF.
      MODIFY pt_fieldcat FROM ls_fcat.
    ENDIF.
  ENDLOOP.
ENDFORM.                               "build_fieldcat
FORM set_drdn_table.
  CHECK go_grid->offline( ) IS INITIAL.
  DATA: lt_dropdown TYPE lvc_t_drop,
        ls_dropdown TYPE lvc_s_drop.
  ls_dropdown-handle = '1'.
  ls_dropdown-value  = 'EN'.
  APPEND ls_dropdown TO lt_dropdown.
  ls_dropdown-handle = '1'.
  ls_dropdown-value  = 'DE'.
  APPEND ls_dropdown TO lt_dropdown.
  CALL METHOD go_grid->set_drop_down_table
    EXPORTING
      it_drop_down = lt_dropdown.
ENDFORM.                                " set_drdn_table
FORM change_display_table USING pv_language pv_rowno TYPE i.
  READ TABLE gt_outtab INDEX pv_rowno.
  SELECT SINGLE * FROM makt INTO gt_outtab WHERE matnr = gt_outtab-matnr AND spras = pv_language.
  IF sy-subrc EQ 0.
    DELETE gt_outtab INDEX pv_rowno.
    INSERT gt_outtab INDEX pv_rowno.
  ELSE.
    CLEAR : gt_outtab-maktx,
            gt_outtab-maktg.
    DELETE gt_outtab INDEX pv_rowno.
    INSERT gt_outtab INDEX pv_rowno.
  ENDIF.
ENDFORM.                    "change_display_table
*       CLASS event_responder IMPLEMENTATION                          *
CLASS lcl_event_responder IMPLEMENTATION.
  METHOD refresh_changed_data.
    READ TABLE er_data_changed->mt_mod_cells INTO ls_changed_cell INDEX 1.
    CALL FUNCTION 'CONVERSION_EXIT_ISOLA_INPUT'
      EXPORTING
        input  = ls_changed_cell-value
      IMPORTING
        output = lv_language.
    PERFORM change_display_table USING lv_language ls_changed_cell-row_id.
    go_grid->refresh_table_display( ).
  ENDMETHOD.                    "click
ENDCLASS.                    "event_responder IMPLEMENTATION
Cheers,
Jose.