gistfile1.rb

class NewYachtModel < ActiveRecord::Base
  belongs_to :new_yacht
  has_many :contents, :class_name => 'NewYachtTopicContent'
  has_many :topics, :class_name => 'NewYachtTopic', :through => :contents

  accepts_nested_attributes_for :contents
end


class NewYachtTopic < ActiveRecord::Base
  belongs_to :new_yacht
  has_many :contents, :class_name => 'NewYachtTopicContent'
  has_many :models, :class_name => 'NewYachtModels', :through => :contents

  accepts_nested_attributes_for :contents
  accepts_nested_attributes_for :models
end


class NewYachtTopicContent < ActiveRecord::Base
  belongs_to :new_yacht_model
  belongs_to :new_yacht_topic
end

class Admin::NewYachtModelsController < Admin::AdminController
  inherit_resources

  def new
    @new_yacht = NewYacht.find(params[:new_yacht_id])
    @new_yacht_model = NewYachtModel.new
  end
end


= link_to '<< Voltar', edit_admin_new_yacht_path(params[:new_yacht_id]), :id => "top_link", :class => "link"

#form
  %dl
    - form_for [:admin, @new_yacht_model], :url => admin_new_yacht_models_path do |form|
      %dt<
        %p= form.error_messages

      %dt= form.hidden_field :new_yacht_id, :value => params[:new_yacht_id]

      - @new_yacht.topics.each do |topic|
        %dt= form.label :topics, topic.name

        - form.fields_for :contents, NewYachtTopicContent.new(:new_yacht_topic => topic) do |content_form|
          %dd= content_form.hidden_field :new_yacht_topic_id
          %dd= content_form.text_field :content

      = form.submit 'Inserir', :class => 'button'