Implementing BADI TRIP_WEB_NUMBER, problem reading a field

Question

Hi All,
Have anyone implemented BADI TRIP_WEB_NUMBER before,
Interface : IF_EX_TRIP_WEB_NUMBER
Method:     USER_EXIT_NUMBER_INTERNAL
I need a help.
In this method i have exporting parameter NUMBER_RANGE TYPE INRI-NRRANGENR
so my requirement is just to change this parameter for particular conditon.
Problem is to make condition i need a field SCHEMA
You can check Structure HEAD_PERIO-SCHEM
or elset T706S OR T706T...
I need to read that field at runtime somehow, how can i achieve that pls help.
i can able to read only the date....
Pls help..
Thanks

Answer 1

Find out the main program name where the variable HEAD_PERIO-SCHEMA is declared. Then you can use the ABAP call stack method to retrieve the variable like below. This method can only be used to read a variable from ABAP call stack memory, that is the variable should be available in the scope of the program which is present in the run time call stack your BADI gets called in.
DATA: lv_name_xvbak(30)  VALUE   '(SAPMV45A)VBAK'.
FIELD-SYMBOLS: <xvbak> TYPE  vbak.
* Retrieve Sales order details from abap stack
ASSIGN (lv_name_xvbak) TO <xvbak>.
IF sy-subrc NE 0.
  EXIT.
ENDIF.
In the above code you can replace SAPMV45A with the main program name where field SCHEMA is available and VBAK with HEAD_PERIO (the structure or internal table where the field you want is available)
For accessing internal tables similarly
DATA:  lv_name_xvbap(30)  VALUE   '(SAPMV45A)XVBAP[]'.
FIELD-SYMBOLS: <xvbap> TYPE TABLE OF vbap.
ASSIGN (lv_name_xvbap) TO <xvbap>.
IF sy-subrc NE 0.
  EXIT.
ENDIF.