嵌套模型形式與多態關聯

Question

我有更多的嵌套窗體的麻煩。這次用我的多態地址模型。任何幫助將不勝感激。

<%= form_for @account do |f| %> 

<%= f.label :account_type %><br /> 
<%= f.text_field :account_type %><br /> 

    <%= f.fields_for :organizations do |builder| %> 
     <%= builder.label :name %><br /> 
     <%= builder.text_field :name %><br /> 
     <%= builder.label :website %><br /> 
     <%= builder.text_field :website %><br /> 

     <%= builder.fields_for :locations do |lb| %> 
      <%= lb.label :phone %><br /> 
      <%= lb.text_field :phone %><br /> 
      <%= lb.label :toll_free_phone %><br /> 
      <%= lb.text_field :toll_free_phone %><br /> 
      <%= lb.label :fax %><br /> 
      <%= lb.text_field :fax %><br /> 

      <%= lb.fields_for :address do |ab| %> 
       <%= ab.label :address1 %><br /> 
       <%= ab.text_field :address1 %><br /> 
       <%= ab.label :address2 %><br /> 
       <%= ab.text_field :address2 %><br /> 
       <%= ab.label :city %><br /> 
       <%= ab.text_field :city %><br /> 
       <%= ab.label :state %><br /> 
       <%= ab.text_field :state %><br /> 
       <%= ab.label :zip %><br /> 
       <%= ab.text_field :zip %><br /> 
      <% end %> 
     <% end %> 
    <% end %> 

<%= f.submit "Add account" %> 
<% end %> 

class Account < ActiveRecord::Base 

    has_many :organizations 

    accepts_nested_attributes_for :organizations 
end 

class Organization < ActiveRecord::Base 

    belongs_to :account 

    has_many :locations 

    accepts_nested_attributes_for :locations 
end 

class Location < ActiveRecord::Base 

    belongs_to :organization 

    has_one :address, :as => :addressable 

end 

class Address < ActiveRecord::Base 

    belongs_to :addressable, :polymorphic => true 
end 

class AccountsController < ApplicationController 

def new 
    @account = Account.new 
    organization = account.organizations.build 
    location = organization.locations.build 
    location.addresses.build 

    @header = "Create account" 
end 

def create 
    @account = Account.new(params[:account]) 
    if @account.save 
     #handle success 
    else 
     render 'new' 
    end 
end 
end 

當試圖通過顯示/賬戶形式/新我收到以下錯誤消息：

NoMethodError in AccountsController#new 

undefined method `addresses' for #<Location:0x18d7718> 
Rails.root: C:/Documents and Settings/Corey Quillen/My  
Documents/rails_projects/shop_manager 

Application Trace | Framework Trace | Full Trace 
app/controllers/accounts_controller.rb:7:in `new' 
Request 

Parameters: 

None 

Answer 1

的問題是，因爲你正在做location.addresses.build當你定義的地址協會作爲has_one。因此，您將需要執行location.build_address。如果你想建立一個belongs_to關聯，那也是一樣的。

這是不可能的address協會本身被稱爲build方法，爲address方法將嘗試加載相關的對象，並返回nil如果不能，並呼籲nilbuild只是不允許。因此，你需要做build_address。