A Nicer Way of Building Records for accepts_nested_attributes_for

gistfile1.rb

class YourModel < ActiveRecord::Base
  has_one :listing
  accepts_nested_attributes_for :listing
  attr_accessible :listing_attributes

  # Make sure we always have a listing
  after_initialize :build_listing, :unless => :listing
end

I've seen various implementations of this before - normally in the controller, or using an after_initialize with a another method. This way is nice because:

• It only uses ActiveRecord methods - we don't need to define anything anywhere in the controller or elsewhere in the model
• It will automatically work for both new models and ones pulled out fo the database without a Listing
• It sets up the implication that we need a Listing for this model, which is nearly always the case when using accepts_nested_attributes_for