Dynamic selection screen

To design selection screen:
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PARAMETERS: p_create TYPE c RADIOBUTTON GROUP rb1 DEFAULT 'X' USER-COMMAND sel,
            p_change TYPE c RADIOBUTTON GROUP rb1 .
SELECTION-SCREEN BEGIN OF BLOCK b1 WITH FRAME TITLE text-001.
SELECT-OPTIONS s_route FOR trolz-route MODIF ID m1.
PARAMETER: p_kunwe TYPE  vawk-kunwe MODIF ID m1.
PARAMETER: p_giday TYPE cacsdayweek MODIF ID m1.
PARAMETER: p_gitime LIKE sy-uzeit DEFAULT  '200000' MODIF ID m1.
SELECTION-SCREEN END OF BLOCK b1.

SELECTION-SCREEN BEGIN OF BLOCK b2 WITH FRAME TITLE text-008.
SELECT-OPTIONS : s_vkorg FOR vbak-vkorg MODIF ID m2,
                 s_kunwe FOR  vawk-kunwe MODIF ID m2.
PARAMETER : p_ktokd type kna1-ktokd MODIF ID m2.
SELECTION-SCREEN END OF BLOCK b2.

*AT SELECTION-SCREEN OUTPUT

AT SELECTION-SCREEN OUTPUT  .

  LOOP AT SCREEN.
    IF screen-name = 'P_GITIME'.
      screen-input = '0'.
      MODIFY SCREEN.
    ENDIF.
  ENDLOOP.
  IF p_create = 'X'.
    LOOP AT SCREEN.
      IF screen-group1 = 'M2'.
        screen-input = 0.
        screen-active = 0.
     ENDIF.

      IF screen-group1 = 'M2'.
        screen-input = 0.
        screen-active = 1.
      ENDIF.

      MODIFY SCREEN.
    ENDLOOP.

  ENDIF.
  IF p_change = 'X'.
    LOOP AT SCREEN.
      IF screen-group1 = 'M1'.
        screen-input = 0.
        screen-active = 0.
      ENDIF.
      IF screen-group1 = 'M1'.
        screen-input = 0.
        screen-active = 1.
      ENDIF.

      MODIFY SCREEN.
    ENDLOOP.
  ENDIF.

*******************************************************************

SELECTION-SCREEN:BEGIN OF BLOCK sales_area WITH FRAME TITLE text-001.
PARAMETERS: p_vkorg LIKE vbak-vkorg  OBLIGATORY.
SELECT-OPTIONS:p_vbeln FOR vbak-vbeln,
               p_audat FOR vbak-audat  OBLIGATORY,
               p_auart FOR vbak-auart,
               p_kunnr FOR vbak-kunnr,
               p_ernam FOR vbak-ernam,
               p_vbtyp FOR vbak-vbtyp,
               p_kschl FOR konh-kschl  NO INTERVALS,
               p_pstyv FOR vbap-pstyv  NO INTERVALS.
SELECTION-SCREEN: END OF BLOCK sales_area.
SELECTION-SCREEN:BEGIN OF BLOCK price_cond WITH FRAME TITLE text-032.
PARAMETERS:p_ovrrd AS CHECKBOX USER-COMMAND  flg1 DEFAULT gcf_x,
           p_fchar AS CHECKBOX USER-COMMAND  flg2 DEFAULT gcf_x,
           p_disp  AS CHECKBOX USER-COMMAND  flg3 .
SELECTION-SCREEN:END OF BLOCK price_cond.
SELECTION-SCREEN:BEGIN OF BLOCK grid_disp WITH FRAME TITLE text-036.
PARAMETERS:p_grid AS CHECKBOX.
SELECTION-SCREEN:END OF BLOCK grid_disp.


**************************************************************
Authority check

* inquiry authority of sales area
    AUTHORITY-CHECK OBJECT lcf_vbak_vko
         ID  lcf_vkorg FIELD p_vkorg
         ID  lcf_vtweg FIELD ldf_vtweg
         ID  lcf_spart FIELD ldf_spart
         ID  lcf_actvt FIELD lcf_03.
    IF sy-subrc <> 0.
*You are not authorized to execute processing [contact the system administrator]
      MESSAGE : e101(zev0101) WITH p_vkorg.
    ENDIF.
  ENDIF.
ENDFORM.                    " CHECK_AUTH
********************************************************************