ruby on rails - Only allow creation of has_many in ActiveAdmin -

i have has_many relation have disabled destroying:

unless f.object.new_record?   f.inputs     f.has_many :foos, allow_destroy: false |foo|       foo.input :bar     end   end end 

currently once i've saved main object , go , edit, can edit created foos. i'd not case , have ability add new ones. how can achieve this?

i can see activeadmin provides allow_destroy , new_record, there isn't analogous allow_edit.

turns out answer staring me in face: new_record?. check whether has_many item new record or not:

f.inputs   f.has_many :foos, allow_destroy: false |foo|     if foo.object.new_record?       foo.input :bar     end   end end