Hi Santanu,
I think you can do this, but I am not sure, just try it out
so I have looked for an exit function and I found this one
*--- call customer function to change ALV settings
CALL FUNCTION 'IREP1_CHANGE_SETTINGS_ALV'
EXPORTING
is_repid = g_repid
is_variant = g_variant
is_form_top_of_page= 'TOP_OF_PAGE_L'
CHANGING
i_grid_inactive = g_grid
is_layout = g_layout
is_print = g_print
it_fieldcat = p_fieldcat_tab[]
it_special_groups = g_fieldgroups_tab[]
it_list_commentary = g_listheader_tab[]
it_event_tab = g_events_tab[].
*--- call customer exit
call customer-function '001'
exporting
is_program = is_repid
is_variant = is_variant
changing
i_grid_inactive = i_grid_inactive
is_layout = is_layout
is_print = is_print
it_fieldcat = it_fieldcat[]
it_special_groups = it_special_groups[]
it_list_commentary = it_list_commentary[].
*--- fill event_tab with form for top-of-page callback if neccessary
if not it_list_commentary[] is initial.
if not is_form_top_of_page is initial.
read table it_event_tab with key name = slis_ev_top_of_page
into h_event.
if sy-subrc = 0.
move is_form_top_of_page to h_event-form.
modify it_event_tab from h_event index sy-tabix.
endif.
endif.
endif.
endfunction.
