simple_form_for錯誤：undefined方法 - 關聯模型

Question

在我的Rails應用程序中，我有兩個關聯的模型，稱爲Magazine和Article。

雜誌

class Magazine < ActiveRecord::Base 
    has_many :articles 
end 

文章

class Article < ActiveRecord::Base 
    belongs_to :magazine 
end 

路線

Magazineapp::Application.routes.draw do 
    resources :magazines do 
    resources :articles 
    end 
end 

schema.rb

create_table "articles", :force => true do |t| 
    t.string "title" 
    t.string "author" 
    t.integer "magazine_id" 
    t.datetime "created_at" 
    t.datetime "updated_at" 
end 

create_table "magazines", :force => true do |t| 
    t.string "title" 
    t.datetime "created_at" 
    t.datetime "updated_at" 
end 

我試圖創建從文章的新頁面關聯到雜誌新文章。因此，我在雜誌的展示頁面創建了一個鏈接，將所選雜誌傳遞到新文章的頁面。

的意見/雜誌/ show.html.erb

<p id="notice"><%= notice %></p> 
<p> 
    <b>Title:</b> 
    <%= @magazine.title %> 
</p> 

<%= link_to 'Edit', edit_magazine_path(@magazine) %> | 
<%= link_to 'Back', magazines_path %> | 
<%= link_to 'New Article', new_magazine_article_path(@magazine) %> 

是在文章的新頁面呈現的部分是：

的意見/用品/ _form.html.erb

<%= simple_form_for([@magazine, @article]) do |f| %> 
    <%= f.error_notification %> 

    <div class="inputs"> 
    <%= f.input :title %> 
    <%= f.input :author %> 
    </div> 

    <div class="actions"> 
    <%= f.button :submit %> 
    </div> 
<% end %> 

而文章的控制器的創建方法是：

def create 

    @magazine = Magazine.find(params[:magazine_id])  
    @article = @magazine.articles.create(params[:article]) 

    respond_to do |format| 
    if @article.save 
     format.html { redirect_to(@article, :notice => 'Article was successfully created.') } 
     format.xml { render :xml => @article, :status => :created, :location => @article } 
    else 
     format.html { render :action => "new" } 
     format.xml { render :xml => @article.errors, :status => :unprocessable_entity } 
    end 
    end 
end 

但是當我嘗試創建相關的雜誌，我得到了錯誤信息的新文章：

magazine_articles GET /magazines/:magazine_id/articles(.:format)   {:action=>"index", :controller=>"articles"} 
         POST /magazines/:magazine_id/articles(.:format)   {:action=>"create", :controller=>"articles"} 
new_magazine_article GET /magazines/:magazine_id/articles/new(.:format)  {:action=>"new", :controller=>"articles"} 
edit_magazine_article GET /magazines/:magazine_id/articles/:id/edit(.:format) {:action=>"edit", :controller=>"articles"} 
    magazine_article GET /magazines/:magazine_id/articles/:id(.:format)  {:action=>"show", :controller=>"articles"} 
         PUT /magazines/:magazine_id/articles/:id(.:format)  {:action=>"update", :controller=>"articles"} 
         DELETE /magazines/:magazine_id/articles/:id(.:format)  {:action=>"destroy", :controller=>"articles"} 
      magazines GET /magazines(.:format)        {:action=>"index", :controller=>"magazines"} 
         POST /magazines(.:format)        {:action=>"create", :controller=>"magazines"} 
     new_magazine GET /magazines/new(.:format)       {:action=>"new", :controller=>"magazines"} 
     edit_magazine GET /magazines/:id/edit(.:format)      {:action=>"edit", :controller=>"magazines"} 
      magazine GET /magazines/:id(.:format)       {:action=>"show", :controller=>"magazines"} 
         PUT /magazines/:id(.:format)       {:action=>"update", :controller=>"magazines"} 
         DELETE /magazines/:id(.:format)       {:action=>"destroy", :controller=>"magazines"} 

我怎樣才能解決這個問題

Showing /home/wilson/magazineapp/app/views/articles/_form.html.erb where line #1 raised: 

undefined method `articles_path' for #<#<Class:0x00000001944070>:0x00000001926ed0> 
Extracted source (around line #1): 

1: <%= simple_form_for([@magazine, @article]) do |f| %> 
2: <%= f.error_notification %> 
3: 
4: <div class="inputs"> 

Request 

Parameters: 

{"magazine_id"=>"2"} 

耙路線？在這種情況下傳遞給simple_form_for的正確參數是什麼？

Answer 1

當你有嵌套的資源時，你必須保證你總是在你的請求之間傳遞更高級別的資源。

您的路線將是您使用耙路線注意到的路線。

的形式應該是這樣的：

<%= simple_form_for([@magazine, @article]) do |f| %> 
    <%= f.error_notification %> 

    <div class="inputs"> 
    <%= f.input :title %> 
    <%= f.input :author %> 
    </div>  
    <div class="actions"> 
    <%= f.button :submit %> 
    </div> 
<% end %> 

這樣，現在你必須在任何地方使用你的文章控制器上的新航線和文章查看頁面，其中將包括該雜誌本身。

控制器您創建的行動將是：

def create 

    @magazine = Magazine.find(params[:magazine_id])  
    @article = @magazine.articles.create(params[:article]) 

    respond_to do |format| 
    if @article.save 
     format.html { redirect_to([@magazine,@article], :notice => 'Article was successfully created.') } 
     format.xml { render :xml => @article, :status => :created, :location => @article } 
    else 
     format.html { render :action => "new" } 
     format.xml { render :xml => @article.errors, :status => :unprocessable_entity } 
    end 
    end 
end 

所以，現在所有的路線應該引用@magazine了。

Answer 2

在您的控制檯中運行rake routes並確保articles_path存在。 似乎應該被命名爲magazines_articles_path(...)