SAP ABAP - Add Custom Screen In Header VL01N/VL02N/VL03N

 1. Append Structure in standard table LIKP

open transaction SE11

Click Append Structure

Create new append structure and activate

2. Implement BADI

goto transaction SE18, select BAdI Name -> LE_SHP_TAB_CUST_HEAD and click display

Select Implementation and click create

double click Name of Implementing Class -> ZCL_IM_E_SHP_TAB_CUST_HEAD

  METHOD if_ex_le_shp_tab_cust_head~activate_tab_page.
    IF sy-uname = 'ABAP01'.
      ef_caption     = 'KB Document'. " screen caption
      ef_program     = 'SAPLZFG_DELV'."sapl followed by the function group created zsd537_head
      ef_position    = 13. " tab position
      ef_dynpro      = '8001'. " screen number
      cs_v50agl_cust = 'X'.
    ENDIF.

  ENDMETHOD.

  METHOD if_ex_le_shp_tab_cust_head~transfer_data_to_subscreen.
    CALL FUNCTION 'ZSET_DELIVERY_HEAD_SCREEN_VAL'
      EXPORTING
        i_likp = is_likp.

  ENDMETHOD.

  METHOD if_ex_le_shp_tab_cust_head~transfer_data_from_subscreen.
    CALL FUNCTION 'ZGET_DELIVERY_HEAD_SCREEN_VAL'
      IMPORTING
        e_likp = cs_likp.

  ENDMETHOD.

3. Create Function Group In SE80

Include LZFG_DELVTOP

DATA :
  ls_ztkbdoc     TYPE ztkbdoc,
  kb_type        TYPE char30,
  kb_number      TYPE char30,
  kb_date        TYPE mkpf-budat.

Create new Subscreen

MODULE status_8001 OUTPUT.
  IF sy-tcode = 'VL03' OR sy-tcode = 'VL03N'.
    LOOP AT SCREEN.
      screen-input = 0.
      MODIFY SCREEN.
    ENDLOOP.
  ENDIF.
ENDMODULE.

Create function module : ZGET_DELIVERY_HEAD_SCREEN_VAL

Create function module : ZSET_DELIVERY_HEAD_SCREEN_VAL

Activate function group and BAdI Implementation and see the result