How to activate next page, last page buttons in ALV reports

Standard ALV calls status STANDARD_FULLSCREEN (program SAPLKKBL) in which next/previous/first/last page is deactivated by default. The same program consist another status APPEND which has these buttons activated. Hence we need to overwrite the PF-STATUS call from STANDARD_FULLSCREEN to APPEND.

1. Copy the APPEND status of program SAPLKKBL to your custom program using t-code SE41. [In this case I have used the same name for status for my program]

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2. Function codes for the page scrolling already exist. Activate your status.

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Changes in the custom program

3. Create subroutine SET_PF_STATUS to set the new PF-STATUS. Note, that this is called dynamically through FM   REUSE_ALV_GRID_DISPLAY

    FORM set_pf_statusUSING rt_extabTYPE slis_t_extab.

      SET PF-STATUS 'APPEND'. 
    ENDFORM.     "Set_pf_status

4. Create subroutine USER_COMMAND which will contain the action upon clicking next/previous/first/last page buttons.

Note, function codes for First Page is ‘P--’, Last Page is ‘P++’, Next Page is ‘P+’ and Previous Page is ‘P-’

FORM user_command USING r_ucomm     LIKE sy-ucomm
                        rs_selfield TYPE slis_selfield.

REFRESH lt_data.
CASE r_ucomm.
WHEN 'P--'.    "First Page
   LOOP AT gt_data INTO lw_data
      WHERE page = 1.
      APPEND lw_data TO lt_data.

      ENDLOOP.

   g_page = 1.
WHEN 'P++'.    "Last Page
   LOOP AT gt_data INTO lw_data
      WHERE page = g_lastpage.
      APPEND lw_data TO lt_data.
      CLEAR lw_data.
   ENDLOOP.
   g_page = g_lastpage.
WHEN 'P+'.     "Next page
   IF g_page EQ g_lastpage.
     EXIT.
   ELSE.
     g_page = g_page + 1.
   ENDIF.
   LOOP AT gt_data INTO lw_data
      WHERE page = g_page.
      APPEND lw_data TO lt_data.
      CLEAR lw_data.
    ENDLOOP.
WHEN 'P-'.     "Previous Page
IF g_page EQ 1.
   EXIT.
ELSE.
   g_page = g_page - 1.
ENDIF.
LOOP AT gt_data INTO lw_data
   WHERE page = g_page.
   APPEND lw_data TO lt_data.
   CLEAR lw_data.
ENDLOOP.
ENDCASE.

ENDFORM.  "User_command

5.  In  REUSE_ALV_GRID_DISPLAY, call the subroutine for new PF-STATUS and USER_COMMAND

CALL FUNCTION 'REUSE_ALV_GRID_DISPLAY'
EXPORTING
i_callback_program          = sy-repid
is_layout                   = lw_layout
i_callback_pf_status_set    = 'SET_PF_STATUS'
i_callback_user_command     = 'USER_COMMAND'

6.  In SET_PF_STATUS, add code to get to selection screen when clicking Back/Exit/Cancel button

FORM set_pf_status USING gt_extab TYPE slis_t_extab .
  SET PF-STATUS 'APPEND'.
  IF sy-ucomm EQ '&F03'
  OR sy-ucomm EQ '&F12'
  OR sy-ucomm EQ '&F15'.
    SUBMIT ztrading_boe WITH SELECTION-TABLE gt_seltab VIA SELECTION-SCREEN.
  ENDIF.
ENDFORM. "Set_pf_status

7.Populate selection screen values in GT_SELTAB in START-OF-SELECTION. This will retain the selection screen values when clicking Back/Exit/Cancel button

START-OF-SELECTION.
* Get selection screen data
PERFORM get_selections_values.

FORM get_selections_values.

CALL FUNCTION 'RS_REFRESH_FROM_SELECTOPTIONS'
EXPORTING
  curr_report     = sy-repid
TABLES
  selection_table = gt_seltab
EXCEPTIONS
  not_found       = 1
  no_report       = 2.
IF sy-subrc <> 0.
  MESSAGE ID sy-msgid TYPE sy-msgty NUMBER sy-msgno
  WITH sy-msgv1 sy-msgv2 sy-msgv3 sy-msgv4.
ENDIF.
ENDFORM.                    " GET_SELECTIONS_VALUES