ABAP - REPORT - How to add user-pushbutton in selection screen

SELECTION-SCREEN: FUNCTION KEY 1,

                                           FUNCTION KEY 2. 

INITIALIZATION.

  DATA iconname TYPE iconname.

  DATA button_text(20) TYPE c.

  DATA quickinfo LIKE smp_dyntxt-quickinfo.

  DATA icon_str(255).

  iconname = 'ICON_TOGGLE_DISPLAY_CHANGE'.

  quickinfo = text-t01.

  CALL FUNCTION 'ICON_CREATE'

    EXPORTING

      name                  = iconname

      text                  = button_text

      info                  = quickinfo

    IMPORTING

      RESULT                = icon_str

    EXCEPTIONS

      icon_not_found        = 1

      outputfield_too_short = 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.

  sscrfields-functxt_01 = icon_str.

  iconname = 'ICON_HEADER'.

  quickinfo = text-t02.

  CALL FUNCTION 'ICON_CREATE'

    EXPORTING

      name                  = iconname

      text                  = button_text

      info                  = quickinfo

    IMPORTING

      RESULT                = icon_str

    EXCEPTIONS

      icon_not_found        = 1

      outputfield_too_short = 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.

  sscrfields-functxt_02 = icon_str.

 

To assign icons, Quickinfo, and appropriate text to the pushbuttons, a data object can be defined of the structured type SMP_DYNTXT from the ABAP dictionary. The ID of the icon, a quickinfo, and the corresponding text
must be assigned to the components of this data object. The content of the whole structure must then be assigned to the component
functxt_0n of the interface work area
sscrfields.