Hi Sumeet,
I suspect you might have missing code in CONNECT_NODES method of the context class that connects BTAdminH to your custom dependent object. A code as follows should be available:
coll_wrapper = btadminh->get_collection_wrapper( ).
SET HANDLER me->XXXXXXX->on_new_focus FOR coll_wrapper ACTIVATION iv_activate.
XXXXXXX = name of your custom object node
Regards,
Shiromani