Tell me about at selection-screen on output

Question

hi,
could u explain at selection-screen on output
any body give the wchich purpose it was used?
i will be waiting for reply.
regards
eswar.

Answer 1

PBO of the Selection Screen
In the PBO of the selection screen, the
AT SELECTION-SCREEN OUTPUT
event is triggered. This event block allows you to modify the selection screen and its fields directly before it is displayed.
Initializations of selections screen fields at this moment always take effect, whereas at the execution of an executable program, initializations at moment INITIALIZATION only take effect at the first program start, and are otherwise overwritten by the previous user inputs at the beginning of AT SELECTION-SCREEN OUTPUT.
REPORT demo_at_selection_screen_pbo.
PARAMETERS: test1(10) TYPE c MODIF ID sc1,
            test2(10) TYPE c MODIF ID sc2,
            test3(10) TYPE c MODIF ID sc1,
            test4(10) TYPE c MODIF ID sc2.
AT SELECTION-SCREEN OUTPUT.
  LOOP AT SCREEN.
    IF screen-group1 = 'SC1'.
      screen-intensified = '1'.
      MODIFY SCREEN.
      CONTINUE.
    ENDIF.
    IF screen-group1 = 'SC2'.
      screen-intensified = '0'.
      MODIFY SCREEN.
    ENDIF.
  ENDLOOP.
The parameters test1 and test3 are assigned to the modification group sc1, while test2 and test4 are assigned to group sc2. During the AT SELECTION-SCREEN OUTPUT event, the INTENSIFIED field of internal table screen is set to 1 or 0, depending on the contents of the group1 field. On the standard selection screen, the lines for test1 and test3 are highlighted while those for test2 and test4 are not, as shown below:
reward if useful
anju