How do you gracefully error/exit an ALV Grid Controls

Question

I have a report that uses ALV grid controls.  Inside the screens, I am opening a file, and need to give an error if the file does not successfully open.  I do not have any problem doing this, BUT when I error, it takes me totally out of the program, and I really just want to get back to the report selection screen.  I have not been successful in finding out how to do this.  Any help is very much appreciated!!  Thanks!

Answer 1

Here is how some of the code looks....this is the initial call into the first screen of the ALV grid.  From the screen 100 of the ALV Grid, I want to be able to hit the green back arrow button and go back to the report selection criteria so that the user can easily change a file name in case they entered it wrong, etc.  Here is the code:
START-OF-SELECTION.
  IF NOT p_ofile IS INITIAL.
    CONCATENATE p_opath p_ofile INTO p_ofile.
  ENDIF.
  IF NOT p_sfile IS INITIAL.
    CONCATENATE p_spath p_sfile INTO p_sfile.
  ENDIF.
  IF NOT p_ifile IS INITIAL.
    CONCATENATE p_ipath p_ifile INTO p_ifile.
  ENDIF.
  IF NOT p_ofile2 IS INITIAL.
    CONCATENATE p_opath p_ofile2 INTO p_ofile2.
  ENDIF.
  IF NOT p_sfile2 IS INITIAL.
    CONCATENATE p_spath p_sfile2 INTO p_sfile2.
  ENDIF.
  IF NOT p_ifile2 IS INITIAL.
    CONCATENATE p_ipath p_ifile2 INTO p_ifile2.
  ENDIF.
  IF NOT p_ofile3 IS INITIAL.
    CONCATENATE p_opath p_ofile3 INTO p_ofile3.
  ENDIF.
  IF NOT p_sfile3 IS INITIAL.
    CONCATENATE p_spath p_sfile3 INTO p_sfile3.
  ENDIF.
  IF NOT p_ofile4 IS INITIAL.
    CONCATENATE p_opath p_ofile4 INTO p_ofile4.
  ENDIF.
  IF NOT p_sfile4 IS INITIAL.
    CONCATENATE p_spath p_sfile4 INTO p_sfile4.
  ENDIF.
  IF NOT p_ofile5 IS INITIAL.
    CONCATENATE p_opath p_ofile5 INTO p_ofile5.
  ENDIF.
  IF NOT p_ofile6 IS INITIAL.
    CONCATENATE p_opath p_ofile6 INTO p_ofile6.
  ENDIF.
  IF NOT p_ofile7 IS INITIAL.
    CONCATENATE p_opath p_ofile7 INTO p_ofile7.
  ENDIF.
  IF NOT p_ofile8 IS INITIAL.
    CONCATENATE p_opath p_ofile8 INTO p_ofile8.
  ENDIF.
  SELECT * FROM zgedwsostmg INTO TABLE xzgedwsostmg.
  SELECT SINGLE delimiter_hex FROM zgedwflcnfg
      INTO g_delimiter_hex
      WHERE kappl = 'V1'.
  g_hex_value = g_delimiter_hex.
END-OF-SELECTION.
  PERFORM load_header_table.
  SET SCREEN 100.
Screen 100 Code
PROCESS BEFORE OUTPUT.
  MODULE status_0100.
  MODULE create_objects.
PROCESS AFTER INPUT.
  MODULE pai_100 at exit-command.
MODULE pai_100 INPUT.
  CASE ok_code.
    WHEN 'BACK'.
      g_back = 'X'.
      PERFORM exit_program.
     exit.
    WHEN 'EXIT'.
      PERFORM exit_program.
    WHEN 'CANC'.
      PERFORM exit_program.
  ENDCASE.
  CLEAR ok_code.
ENDMODULE.                 " PAI  INPUT
FORM exit_program.
  CALL METHOD g_custom_container1->free.
  IF NOT g_custom_container2 IS INITIAL.
    CALL METHOD g_custom_container2->free.
  ENDIF.
  CALL METHOD cl_gui_cfw=>flush.
  IF sy-subrc NE 0.
add your handling, for example
    CALL FUNCTION 'POPUP_TO_INFORM'
         EXPORTING
              titel = g_repid
              txt2  = sy-subrc
              txt1  = 'Error in Flush'(500).
  ENDIF.
LEAVE PROGRAM.
set screen 0.
leave screen.
  leave screen.
leave to screen 1000.
CALL SELECTION-SCREEN 1000.
leave to list-processing.
exit.
leave to screen 0.
ENDFORM.                    " exit_program
As you can see by all the commented lines, I have tried several ways to make this work, but without success.  Thanks again for any help!!