SELECTION SCREEN 상 입력 파라미터의 상태 변경은 SCREEN 속성을 이용하면 가능합니다.

단, 위와 같은 상황에선 라디오 버튼 1,2 와 3,4는 각각의 그룹으로 묶여 있어야 하며

이벤트는 AT SELECTION-SCREEN OUTPUT 블럭에 구현 하시면 될것 같습니다.

PARAMETERS : pa_ra01 RADIOBUTTON GROUP gr1 DEFAULT 'X' USER-COMMAND zzzz,
             pa_ra02 RADIOBUTTON GROUP gr1,
             pa_ra03 RADIOBUTTON GROUP gr1,
             pa_ra04 RADIOBUTTON GROUP gr1.

AT SELECTION-SCREEN OUTPUT.

  LOOP AT SCREEN.
    "" 1, 2번째는 항상 선택 가능하게...
    IF screen-name = 'PA_RA01' OR
       screen-name = 'PA_RA02'.
      screen-input = '1'.
      MODIFY SCREEN.
      CONTINUE.
    ENDIF.

    CASE 'X'.
      WHEN pa_ra01.
        CASE screen-name.
          WHEN 'PA_RA04'. screen-input = '1'.
          WHEN OTHERS.    screen-input = '0'.
        ENDCASE.
      WHEN pa_ra02.
        CASE screen-name.
          WHEN 'PA_RA04'. screen-input = '0'.
          WHEN OTHERS.    screen-input = '1'.
        ENDCASE.
      WHEN pa_ra03.
      WHEN pa_ra04.
    ENDCASE.

    MODIFY SCREEN.

  ENDLOOP.

대충 이정도하면 되지 않을까 싶네요. INVISIBLE 이나 ACTIVE 속성으로 하면

라디오버튼이 안보여서 편의상 INPUT 으로 제어했습니다.

SELECTION-SCREEN BEGIN OF LINE.
SELECTION-SCREEN COMMENT 2(10) FOR FIELD r_cars.
PARAMETERS : r_cars RADIOBUTTON GROUP rgb USER-COMMAND usd .
SELECTION-SCREEN END OF LINE.

SELECTION-SCREEN BEGIN OF LINE.
SELECTION-SCREEN COMMENT 20(10) FOR FIELD r_toyota .
PARAMETERS : r_toyota RADIOBUTTON GROUP rgb1 DEFAULT 'X'.
SELECTION-SCREEN END OF LINE.

SELECTION-SCREEN BEGIN OF LINE.
SELECTION-SCREEN COMMENT 20(10) FOR FIELD r_ford .
PARAMETERS : r_ford RADIOBUTTON GROUP rgb1 .
SELECTION-SCREEN END OF LINE.

SELECTION-SCREEN BEGIN OF LINE.
SELECTION-SCREEN COMMENT 2(10) FOR FIELD r_bus .
PARAMETERS : r_bus RADIOBUTTON GROUP rgb DEFAULT 'X'.
SELECTION-SCREEN END OF LINE.

SELECTION-SCREEN BEGIN OF LINE.
SELECTION-SCREEN COMMENT 20(10) FOR FIELD r_volvo .
PARAMETERS : r_volvo RADIOBUTTON GROUP rgb2 USER-COMMAND com.
SELECTION-SCREEN END OF LINE.

SELECTION-SCREEN BEGIN OF LINE.
SELECTION-SCREEN COMMENT 20(10) FOR FIELD r_merced .
PARAMETERS : r_merced RADIOBUTTON GROUP rgb2 DEFAULT 'X'.
SELECTION-SCREEN END OF LINE.

SELECTION-SCREEN BEGIN OF LINE.
SELECTION-SCREEN COMMENT 40(10) FOR FIELD r_single .
PARAMETERS : r_single RADIOBUTTON GROUP rgb3 DEFAULT 'X'.
SELECTION-SCREEN END OF LINE.

SELECTION-SCREEN BEGIN OF LINE.
SELECTION-SCREEN COMMENT 40(10) FOR FIELD r_double.
PARAMETERS : r_double RADIOBUTTON GROUP rgb3.
SELECTION-SCREEN END OF LINE.

AT SELECTION-SCREEN OUTPUT. " AT SELECTION-SCREEN OUTPUT
  IF r_cars = 'X'. " If R_CURS radiobutton is selected
    LOOP AT SCREEN . " Looping at screen
      IF screen-name CS 'R_VOLVO'  OR
         screen-name CS 'R_MERCED' OR
         screen-name CS 'R_SINGLE' OR
         screen-name CS 'R_DOUBLE'.
        screen-active = 0. " Hiding the R_VOLVO, R_MERCED.
        MODIFY SCREEN.
      ENDIF.
    ENDLOOP.
  ELSE.
    LOOP AT SCREEN .
      IF screen-name CS 'R_TOYOTA' OR
         screen-name CS 'R_FORD'.

        screen-active = 0.
        MODIFY SCREEN.

      ELSEIF r_volvo NE 'X'        AND
            ( screen-name CS 'R_SINGLE' OR
              screen-name CS 'R_DOUBLE' ).
        screen-active = 0.
        MODIFY SCREEN.
      ENDIF.
    ENDLOOP.
  ENDIF.

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