Disable Multiple Selection Button in Selection Screen

For a requirement, I needed to disable the “multiple selection button” (boxed in red in screenshot below) from the selection screen when P_CUM (that’s CUMulative for you imaginative types) radio-button was selected. I was going crazy searching the forums over at http://sdn.sap.com but I really didn’t find anything usable. You see, the “multiple selection button” acts as an array of input. So for the screenshot, S_WERKS can have more than one input value.

I even looked into CALL FUNCTION ‘SELECT_OPTIONS_RESTRICT’ to no avail. So I suggested to my functional counterpart a work-around that the program will only get the 1^st input value. Lo and behold, my functional designer suggested I do the ff.:

LOOP AT SCREEN.

  IF screen-group3 = ‘VPU’.

    screen-input = 0.

    MODIFY SCREEN.

  ENDIF.

ENDLOOP.

And it worked.