regarding BADI

can any one help me out in implementing the badi vendor_data_add and vendor_add_data_cs

what i have to write in the badi to implement mmy own sub screen

in which method i need to write the code and how to get the data to my screen

i dont have any idea on badis

pls let me know with sample code for he same badi

vendor_data_add and vendor_data_add_cs.

pls let me know in which method i have to write code and what i have to write to implement the screen badi..............

very urgent...........

regards ,

siva.