ALV Grid custom F4 help works but then shows No help found

I have a program that displays an editable ALV grid, with a custom F4 help for the field "No." handled via the event onf4. My custom F4 help is displayed and the selected value is returned correctly.

However every time after the custom F4 help closes, another window opens saying "No input help is available".

How to get rid of this supplementary popup?

Thanks.

Here's my code:

CLASS lcl_app DEFINITION.
  PUBLIC SECTION.
    METHODS constructor.
    METHODS display.
    METHODS on_onf4
                  FOR EVENT onf4 OF cl_gui_alv_grid
      IMPORTING e_fieldname es_row_no e_fieldvalue.
    DATA: grid        TYPE REF TO cl_gui_alv_grid,
          table_spfli TYPE TABLE OF spfli.
ENDCLASS.

CLASS lcl_app IMPLEMENTATION.

  METHOD constructor.
    SELECT * FROM spfli INTO TABLE table_spfli.
    grid = NEW cl_gui_alv_grid(
        i_parent = cl_gui_container=>screen0 ).
    SET HANDLER on_onf4 FOR grid.
    grid->register_f4_for_fields(
        it_f4 = VALUE #( ( fieldname = 'CONNID' register = 'X' chngeafter = 'X' ) ) ).
  ENDMETHOD.

  METHOD display.
    DATA(fcat) = VALUE lvc_t_fcat(
        ( fieldname = 'CARRID' ref_table = 'SPFLI' )
        ( fieldname = 'CONNID' ref_table = 'SPFLI' f4availabl = 'X' ) ).
    grid->set_table_for_first_display(
        EXPORTING is_layout      = VALUE #( edit = 'X' )
        CHANGING it_outtab       = table_spfli
                 it_fieldcatalog = fcat
        EXCEPTIONS OTHERS = 4 ).
  ENDMETHOD.

  METHOD on_onf4.
    DATA return TYPE TABLE OF ddshretval.
    IF e_fieldname = 'CONNID'.
      SELECT DISTINCT connid FROM spfli INTO TABLE @DATA(table_connid).
      CALL FUNCTION 'F4IF_INT_TABLE_VALUE_REQUEST'
        EXPORTING
          retfield        = 'CONNID'
          value_org       = 'S'
        TABLES
          value_tab       = table_connid
          return_tab      = return
        EXCEPTIONS
          parameter_error = 1
          no_values_found = 2
          OTHERS          = 3.
      IF sy-subrc = 0 AND return IS NOT INITIAL.
        FIELD-SYMBOLS <table_modi> TYPE lvc_t_modi.
        ASSIGN er_event_data->m_data->* TO <table_modi>.
        <table_modi> = VALUE #( 
            BASE <table_modi> 
            ( row_id    = es_row_no-row_id
              fieldname = e_fieldname 
              value     = return[ 1 ]-fieldval ) ).
      ENDIF.
    ENDIF.
  ENDMETHOD.

ENDCLASS.

PARAMETERS dummy.

AT SELECTION-SCREEN OUTPUT.
  NEW lcl_app( )->display( ).

Solution

There's a flag er_event_data->m_event_handled which needs to be set to 'X' in the F4 method handler to say that the F4 was actually managed by the custom handling, otherwise the ALV grid attempts displaying the standard F4 (there was no standard F4 in my case hence the popup).

First add the ER_EVENT_DATA parameter in the method declaration :

    METHODS on_onf4
                  FOR EVENT onf4 OF cl_gui_alv_grid
      IMPORTING e_fieldname es_row_no e_fieldvalue
                  er_event_data.

Inside the method ON_ONF4, set the flag :

er_event_data->m_event_handled = 'X'.

Final code with "<=== showing the two added lines:

CLASS lcl_app DEFINITION.
  PUBLIC SECTION.
    METHODS constructor.
    METHODS display.
    METHODS on_onf4
      FOR EVENT onf4 OF cl_gui_alv_grid
      IMPORTING e_fieldname es_row_no e_fieldvalue
                er_event_data.                                "<=========
    DATA: grid        TYPE REF TO cl_gui_alv_grid,
          table_spfli TYPE TABLE OF spfli.
ENDCLASS.

CLASS lcl_app IMPLEMENTATION.

  METHOD constructor.
    SELECT * FROM spfli INTO TABLE table_spfli.
    grid = NEW cl_gui_alv_grid(
        i_parent = cl_gui_container=>screen0 ).
    SET HANDLER on_onf4 FOR grid.
    grid->register_f4_for_fields(
        it_f4 = VALUE #( ( fieldname = 'CONNID' register = 'X' chngeafter = 'X' ) ) ).
  ENDMETHOD.

  METHOD display.
    DATA(fcat) = VALUE lvc_t_fcat(
        ( fieldname = 'CARRID' ref_table = 'SPFLI' )
        ( fieldname = 'CONNID' ref_table = 'SPFLI' f4availabl = 'X' ) ).
    grid->set_table_for_first_display(
        EXPORTING is_layout      = VALUE #( edit = 'X' )
        CHANGING it_outtab       = table_spfli
                 it_fieldcatalog = fcat
        EXCEPTIONS OTHERS = 4 ).
  ENDMETHOD.

  METHOD on_onf4.
    DATA return TYPE TABLE OF ddshretval.
    IF e_fieldname = 'CONNID'.
      SELECT DISTINCT connid FROM spfli INTO TABLE @DATA(table_connid).
      CALL FUNCTION 'F4IF_INT_TABLE_VALUE_REQUEST'
        EXPORTING
          retfield        = 'CONNID'
          value_org       = 'S'
        TABLES
          value_tab       = table_connid
          return_tab      = return
        EXCEPTIONS
          parameter_error = 1
          no_values_found = 2
          OTHERS          = 3.
      IF sy-subrc = 0 AND return IS NOT INITIAL.
        FIELD-SYMBOLS <table_modi> TYPE lvc_t_modi.
        ASSIGN er_event_data->m_data->* TO <table_modi>.
        <table_modi> = VALUE #(
            BASE <table_modi>
            ( row_id    = es_row_no-row_id
              fieldname = e_fieldname
              value     = return[ 1 ]-fieldval ) ).
        er_event_data->m_event_handled = 'X'.                    "<=========
      ENDIF.
    ENDIF.
  ENDMETHOD.

ENDCLASS.

PARAMETERS dummy.

AT SELECTION-SCREEN OUTPUT.
  NEW lcl_app( )->display( ).