hi all experts
can i use <u><b>BAdI</b></u>, how i do that.
please tell me the steps..
i would like to allow or disallow to change material description in short text field at follow t-code ::
ME51N Create Purchase Requisition
ME52N Change Purchase Requisition
ME21N Create Purchase Order
ME22N Change Purchase Order
IW31 Create Maintenance Order
IW32 Change Maintenance Order
CJ20N Project Builder
thanks