How to gray out certain fields on the selection screen based on the radio b

Question

HI All,
  I have an ALV report. On the selection screen I have 2 radio buttons ..for eg..A and B.
When radio button A(its on by default) is on..certain fields not relevant to this should be grayed out. Similarly when radio button B is on, certain fields should be grayed out.
I did the AT SELECTION SCREEN OUTPUT and also did the
LOOP AT SCREEN....ENDLOOP logic. The logic works but when I click the radio button B...the screen fields automatically does not gray out. I have to press ENTER and then its grays out.
I know a USER_COMMAND needs to be attached.
Can anyone give me a step by step details of how to do this. I truly appreciate it. if a screen painter thing is required..please give me the tcode and step by step detail to do this.
Thanks

Answer 1

Try this one too:
REPORT ztest.
TABLES: mara,
        bkpf.
CONSTANTS:
              c_pos(3) TYPE c VALUE 'POS',
              c_acc(3) TYPE c VALUE 'ACC',
              c_all(3) TYPE c VALUE 'ALL',
              c_x TYPE c VALUE 'X'.
The Selection Screen Definition
SELECTION-SCREEN BEGIN OF BLOCK b_0 WITH FRAME TITLE text-000.
SELECT-OPTIONS: s_mara FOR mara-matnr.
SELECTION-SCREEN END OF BLOCK b_0.
SELECTION-SCREEN BEGIN OF BLOCK b_1 WITH FRAME TITLE text-037.
PARAMETER: rb_all RADIOBUTTON GROUP rb1 USER-COMMAND rad default 'X',
           rb_acc RADIOBUTTON GROUP rb1.
SELECTION-SCREEN END OF BLOCK b_1.
SELECTION-SCREEN BEGIN OF BLOCK b_2 WITH FRAME TITLE text-011. "Acct
SELECT-OPTIONS:   s_blrtc1 FOR bkpf-blart MODIF ID acc,
                  s_blrti1 FOR bkpf-blart MODIF ID acc.
SELECTION-SCREEN END OF BLOCK b_2.
SELECTION-SCREEN BEGIN OF BLOCK b_3 WITH FRAME TITLE text-011. "Acct
SELECT-OPTIONS:   s_blrtc2 FOR bkpf-blart MODIF ID all,
                  s_blrti2 FOR bkpf-blart MODIF ID all,
                  s_blrtv2 FOR bkpf-blart MODIF ID all.
SELECTION-SCREEN END OF BLOCK b_3.
AT SELECTION-SCREEN OUTPUT
AT SELECTION-SCREEN OUTPUT.
  PERFORM f0200_screenfield_hide_logic.
initialization.
  PERFORM f0200_screenfield_hide_logic.
      FORM f0200_screenfield_hide_logic                             *
FORM f0200_screenfield_hide_logic.
  LOOP AT SCREEN.
    IF rb_acc = c_x.
      IF screen-group1 = c_all.
        screen-active = 0.
      ELSE.
        screen-active = 1.
      ENDIF.
    ENDIF.
    MODIFY SCREEN.
    IF rb_all = c_x.
      IF screen-group1 = c_acc.
        screen-active = 0.
      ELSE.
        screen-active = 1.
      ENDIF.
    ENDIF.
    MODIFY SCREEN.
  ENDLOOP.
ENDFORM.                    " F0200_SCREENFIELD_HIDE_LOGIC