How can i used pai in screen 1000 to change the select-options field?

Question

hi,all.
I want used pai to change the select-options field,but it can't works.
the mainly code is:
REPORT  ZTEST99.
TABLES :MARA,MAKT,MARC.
SELECTION-SCREEN BEGIN OF BLOCK B0 WITH FRAME TITLE TITLE0 .
select-options:s_matnr for mara-matnr,
               s_werks for marc-werks MODIF ID ID1.
SELECTION-SCREEN END OF BLOCK B0.
parameters:p_flag as checkbox.
at selection-screen OUTPUT.
   LOOP AT SCREEN.
   IF P_FLAG = 'X' .
   IF screen-group1 = 'ID1'.
         screen-input = '0'.
    ELSE.
      screen-input = '1'.
    ENDIF.
    MODIFY SCREEN.
ENDIF.
    ENDLOOP.
START-OF-SELECTION.
CALL SCREEN 1000.
when i click p_flag,then i want to change s_werks from OBLIGATORY to no OBLIGATORY.
how can i realized?
Thanks for all.
Sun

Answer 1

Hi ,
change your code like this.
Change in your code:
SELECTION-SCREEN BEGIN OF SCREEN 100.
SELECT-OPTIONS : s_matnr for mara-matnr,
s_werks for marc-werks MODIF ID ID1.
SELECTION-SCREEN END OF SCREEN 100 .
At selection-screen.
if sy-dynnr = '100'.
IF P_FLAG = 'X' .
LOOP AT SCREEN.
IF screen-group1 = 'ID1'.
screen-required = '0'.
ENDIF.
MODIFY SCREEN.
ENDIF.
ENDLOOP.
else.
LOOP AT SCREEN.
IF screen-group1 = 'ID1'.
screen-required = 1.
ENDIF.
MODIFY SCREEN.
ENDIF.
ENDLOOP.
my code :
REPORT  Z50871_SELECTOPS_DYNAMIC.
PARAMETERS : CH_EBELN AS CHECKBOX,
             CH_VBELN AS CHECKBOX.
DATA: V_EBELN TYPE EKKO-EBELN,
      V_VBELN TYPE VBAK-VBELN.
SELECTION-SCREEN BEGIN OF SCREEN 100.
SELECT-OPTIONS : EBELN FOR V_EBELN MODIF ID G1,
                 VBELN FOR V_VBELN MODIF ID G2.
SELECTION-SCREEN END OF SCREEN 100 .
AT SELECTION-SCREEN OUTPUT.
  IF SY-DYNNR = 100.
    IF CH_EBELN = 'X' AND
       CH_VBELN = ''.
      LOOP AT SCREEN.
        IF SCREEN-GROUP1 EQ 'G1'.
          SCREEN-ACTIVE = '1'.
        ELSE.
          SCREEN-ACTIVE = '0'.
        ENDIF.
        MODIFY SCREEN.
      ENDLOOP.
    ELSEIF CH_VBELN = 'X' AND
       CH_EBELN = '' .
      LOOP AT SCREEN.
        IF SCREEN-GROUP1 EQ 'G2'.
          SCREEN-ACTIVE = '1'.
        ELSE.
          SCREEN-ACTIVE = '0'.
        ENDIF.
        MODIFY SCREEN.
      ENDLOOP.
    ELSEIF CH_EBELN = 'X' AND CH_VBELN = 'X'.
      LOOP AT SCREEN.
        IF SCREEN-GROUP1 EQ 'G1'
           OR SCREEN-GROUP1 EQ 'G2' .
          SCREEN-ACTIVE = '1'.
        ENDIF.
        MODIFY SCREEN.
      ENDLOOP.
    ENDIF.
  ENDIF.
AT SELECTION-SCREEN.
IF SY-DYNNR = 1000.
  IF CH_EBELN = 'X' OR CH_VBELN = 'X'.
    CALL SELECTION-SCREEN 100.
  ELSE.
    MESSAGE I000(Z50871MSG) WITH 'Please select atleast one checkbox'.
  ENDIF.
ENDIF.
regards
Sandeep Reddy