Ruby on rails 3.2 递归部分（Ruby on Rails）中的即时加载

我有一个带有自联接的模型：

  class Audience < ActiveRecord::Base
   has_many :children, class_name: "Audience", foreign_key: "parent_id"
   belongs_to :parent, class_name: "Audience"
  end 

提供程序有多个受众，其中有多个子受众（在受众表中）

<%= render 'checkbox_for_children', :audience => root_audience %>

<% children = audience.children %>

<ul class="list-unstyled">
  <% children.each do |child| %>
    <li>
      <% if child.targetable.present? %>
        <%= check_box_tag("demographic_data[#{child.name}]", child.demographic_id) %>
        <%= child.name %>
        <% if child.children.present? %>
           <%= render 'checkbox_for_children', :audience => child %>
        <% end %>
      <% else %>
        <%= child.name %>
        <% if child.children.present? %>
           <%= render 'checkbox_for_children', :audience => child %>
        <% end %>
      <% end %>
    </li>
  <% end %>
</ul>  

  def add_demographic
    @relevant_providers = Provider.have_audience
    render "add_demographic"
  end