Imagine I have the following models:
class Translation < ActiveRecord::Base
has_many :localizations
end
class Localization < ActiveRecord::Base
belong
I think you can try using virtual attribute for this
Example(not tested)
class Localization < ActiveRecord::Base
attr_accessor :new_word #virtual attribute
attr_accessible :word_id, :content, :new_word
belongs_to :translation
before_save do
unless @new_word.blank?
self.word = Word.create({:name => @new_word})
end
end
end
The main idea is to create and store new Word instance before saving localization and use it instead of word_id from drop-down.
ActiveAdmin.register Localization do
form do |f|
f.input :word
f.input :content
f.input :new_word, :as => :string
end
end
There is great rails-cast about virtual attributes http://railscasts.com/episodes/167-more-on-virtual-attributes