I have some requirements to add subsrceen in VA01 transaction. I have tried EXITs but didn't get much even i tried for BADIs by searching "Cl_EXITHANDLER" but found only one method:
CALL METHOD CL_EXITHANDLER=>GET_INSTANCE
EXIT_NAME = 'EHS_PS_002'
NULL_INSTANCE_ACCEPTED = 'X'
ACT_IMP_EXISTING = EHS_PS_002_ACTIVE
INSTANCE = L_BADI_INSTANCE
OTHERS = 1.
Please let me know how to proceed to add subscreen in VA01.