如何在创建方法中不访问params的情况下将实例放置在页面上

Question

我有三个模型，Subscription、Show和Episode。Subscription的作用是解析:url列中的提要，并实例化Show和Episode，用Feedjira属性填充它们的列。

我只能在转到shows/1/episodes/1时访问剧集，在Shows节目视图中使用<%= render @show.episodes %>不起作用，也不会出现任何错误。

在Rails入门指南中，他们将其用作Comment创建方法，从而实现了这一点。

@article = Article.find(params[:article_id])
@comment = @article.comments.create(comment_params)
redirect_to article_path(@article)

是因为缺少params造成的吗？如果是这样，我将如何在这个方法中使用params？

def create
    @subscription = Subscription.new(subscription_params)
    if @subscription.save
        @show = Show.new
        @episodes = []
        # Feed
        @feed = Feedjira::Feed.fetch_and_parse @subscription.url
        # Show
        @show.title = @feed.title
        @show.description = @feed.description
        @show.genre = @feed.itunes_categories
        @show.url = @feed.url
        @show.logo = @feed.itunes_image
        @show.save
        # Episode
        @feed.entries.each do |item|
            @episodes.push(item)
        end
        @episodes.each do |item|
            @episode = @show.episodes.create
            @episode.title = item.title
            @episode.description = item.summary
            @episode.release_date = item.published
            @episode.show_id = @show
            @episode.save
        end
        redirect_to @subscription
    end
end

episodes/_episode.hmtl.erb

<ul>
    <li>
        <%= episode.title %>
    </li>
    <li>
        <%= episode.description %>
    </li>
    <li>
        <%= episode.url %>
    </li>
    <li>
        <%= episode.release_date %>
    </li>
    <li>
        <%= episode.show_id %>
    </li>
</ul>

shows/show.html.erb

<h1>Showing Show</h1>
<h2><%= @show.title %></h2>
<%= render @show.episodes %>

---

添加我的路线和模型以防出现问题：

routes.rb

Rails.application.routes.draw do
  resources :shows do
    resources :episodes
  end
  resources :subscriptions
  root 'subscriptions#index'
end

show.rb

class Show < ActiveRecord::Base
    has_many :episodes, dependent: :destroy
end

episode.rb

class Episode < ActiveRecord::Base
    belongs_to :show
end

subscription.rb

class Subscription < ActiveRecord::Base
    validates :url, uniqueness: true
end

Answer 1

似乎只需要更改

<%= render @show.episodes %>

至

<%= render partial: "episodes/episode", collection: @show.episodes %>

http://guides.rubyonrails.org/action_view_overview.html#partials

小建议：不要把你们的逻辑放在控制器里。