SAP Help The following code demonstrates how to modify report selection screen fields









Modify Selection Screen(LOOP AT SCREEN)

Example code for for modifying Selection screen from within ABAP code: 


**************************************************************
*AT SELECTION-SCREEN OUTPUT.
AT SELECTION-SCREEN OUTPUT.

loop at screen.
  if screen-name eq 'PNPS$MSL'.
    screen-active = 0.
  endif.
  modify screen.
endloop.

Also see example ABAP report which modifies a selection dynamically based on button press, this is a full code listing for a working program that changes the selection screen depending on which custom button is pressed.