Dynamic fields creation on selection screen

Question

Good evening everybody!
I've got the following problem for solving:
Imagine the following situation:
on the selection-screen there are some input fields in one line and a button after them. By pressing that button (e.g. it's name is "Add line") the same fields should be duplicated so many times as many times that button pressed. By pressing another button (e.g. it's name is "Delete line") one last line should be deleted. The mechanism is similar to adding lines in a screen table. What is the solution of this problem?
So: by pressing an "Add line" button on a screen identical fields should be created on the same selection-screen and deleted by pressing "Delete line".
Thanks in advance!

Answer 1

Here's a way to do it.
DEFINE aline.
  selection-screen: begin of line.
  parameters: inp&1(5) type c modif id l&1.
  selection-screen position 15.
  parameters: inp10&1(5) type c modif id l&1.
  selection-screen pushbutton 25(5) pb_&1 user-command add
     modif id a&1.
  selection-screen pushbutton 31(5) pb_10&1 user-command del
     modif id d&1.
  selection-screen end   of line.
END-OF-DEFINITION.
TABLES: sscrfields.
DATA:
  max_lines         TYPE i VALUE 20,
  fldname(60)       TYPE c,
  lines(2)          TYPE n VALUE 1,
  cnt(2)            TYPE n VALUE 1.
FIELD-SYMBOLS:
  <fld>     TYPE ANY.
aline 01.
aline 02.
aline 03.
aline 04.
aline 05.
aline 06.
aline 07.
aline 08.
aline 09.
aline 10.
aline 11.
aline 12.
aline 13.
aline 14.
aline 15.
aline 16.
aline 17.
aline 18.
aline 19.
aline 20.
*---------------------------------------------------- Push Button
AT SELECTION-SCREEN.
  CASE sscrfields-ucomm.
    WHEN 'ADD'.
      CHECK lines LT max_lines.
      lines = lines + 1.
    WHEN 'DEL'.
      CHECK lines GT 1.
      lines = lines - 1.
  ENDCASE.
AT SELECTION-SCREEN OUTPUT.
  LOOP AT SCREEN.
    IF screen-group1 CP 'A*'.
      IF screen-group1+1(2) NE lines.
        screen-active = 0.
      ELSE.
        IF lines LT max_lines.
          screen-active = 1.
        ELSE.
          screen-active = 0.
        ENDIF.
      ENDIF.
    ENDIF.
    IF screen-group1 CP 'D*'.
      IF screen-group1+1(2) NE lines.
        screen-active = 0.
      ELSE.
        IF lines = 1.
          screen-active = 0.
        ELSE.
          screen-active = 1.
        ENDIF.
      ENDIF.
    ENDIF.
    IF screen-group1 CP 'L*'.
      IF screen-group1+1(2) GT lines.
        screen-active = 0.
      ELSE.
        screen-active = 1.
      ENDIF.
    ENDIF.
    MODIFY SCREEN.
  ENDLOOP.
INITIALIZATION.
  cnt = 1.
  WHILE cnt LE max_lines.
    CONCATENATE 'PB_' cnt INTO fldname.
    ASSIGN (fldname) TO <fld>.
    <fld> = 'Add'.
    CONCATENATE 'PB_10' cnt INTO fldname.
    ASSIGN (fldname) TO <fld>.
    <fld> = 'Del'.
    cnt = cnt + 1.
  ENDWHILE.
Edited by: Paul Chapman on Jul 1, 2008 1:06 PM