Event for header click in ALV grid?

Question

Is it possible to catch single button click on the ALV Grid column header ? I know about possibilities to catch double_click, create event for the hotspot on the cell. I have not found yet one header click. (I do not want to provide sort or any other data options). Only thing I found is event click_col_header OF cl_gui_alv_grid but it is protected so I am not able to provide my action. Thank you in advance !

Answer 1

Yes. Here is how to do it with CL_GUI_ALV_GRID:

• Set the ALV layout setting SGL_CLK_HD = 'X' (this activates the sorting of rows based on the clicked column)
• Redefine the sorting behavior with your own code, by handling the event BEFORE_USER_COMMAND and set a new command with the method SET_USER_COMMAND
• Define the new behavior you want during the event USER_COMMAND
• Use the method GET_SELECTED_COLUMNS to know which column has been clicked

(PS: if one wonders, CL_GUI_ALV_GRID has the event CLICK_COL_HEADER, but it's never triggered)

Here is a demo (also posted below Raymond answer in the SAP forum):

CLASS lcl_alv DEFINITION.
  PUBLIC SECTION.
    METHODS constructor.
    METHODS free.
    METHODS on_before_user_command FOR EVENT before_user_command OF cl_gui_alv_grid IMPORTING e_ucomm.
    METHODS on_user_command FOR EVENT user_command OF cl_gui_alv_grid IMPORTING e_ucomm.
    DATA go_alv TYPE REF TO cl_gui_alv_grid.
    DATA gt_sflight TYPE TABLE OF sflight.
ENDCLASS.

CLASS lcl_alv IMPLEMENTATION.

  METHOD constructor.
    CREATE OBJECT go_alv
      EXPORTING
        i_parent = cl_gui_container=>screen0.

    SET HANDLER on_user_command FOR go_alv.
    SET HANDLER on_before_user_command FOR go_alv.

    SELECT * FROM sflight INTO TABLE gt_sflight.
    go_alv->set_table_for_first_display(
        EXPORTING
          i_structure_name = 'SFLIGHT'
          is_layout = VALUE #( sgl_clk_hd = abap_true )
        CHANGING
          it_outtab = gt_sflight ).
  ENDMETHOD.

  METHOD free.
    go_alv->free( ).
  ENDMETHOD.

  METHOD on_before_user_command.
    CASE e_ucomm.
      WHEN go_alv->mc_fc_sort.
        go_alv->set_user_command( i_ucomm = 'ZZSORT' ).
    ENDCASE.
  ENDMETHOD.

  METHOD on_user_command.
    CASE e_ucomm.
      WHEN 'ZZSORT'.
        go_alv->get_selected_columns( IMPORTING et_index_columns = data(columns) ).
        MESSAGE |Columns: { COND #( WHEN lines( columns ) > 0 THEN columns[ 1 ]-fieldname ) }| TYPE 'I'.
    ENDCASE.
  ENDMETHOD.

ENDCLASS.

DATA go_alv TYPE REF TO lcl_alv.

PARAMETERS dummy.

AT SELECTION-SCREEN OUTPUT.
  IF go_alv IS NOT BOUND.
    go_alv = NEW lcl_alv( ).
  ENDIF.

AT SELECTION-SCREEN ON EXIT-COMMAND.
  go_alv->free( ).
  FREE go_alv.