我正在尝试关注Ryan Bates 截屏视频,但收到一条错误消息。我做了以下事情:
1) 创建表
class CreateComments < ActiveRecord::Migration
def self.up
create_table :comments do |t|
t.references :commentable, :polymorphic => true
2) 设置模型
class Comment < ActiveRecord::Base
belongs_to :commentable, :polymorphic => true
class Product < ActiveRecord::Base
has_and_belongs_to_many :categories
has_many :comments, :as => :commentable
class Category < ActiveRecord::Base
has_and_belongs_to_many :products
has_many :comments, :as => :commentable
3)更改控制器显示动作
class CategoriesController < ApplicationController
def show
@category = Category.find_by_permalink(params[:id])
@commentable = @category
@comment = Comment.new(:commentable => @category)
end
4) 向模板views/categories/show.html.erb 添加表单
<% form_for [@commentable, Comment.new] do |f| %>
<p>
<%= f.label :name %><br />
<%= f.text_field :name %>
</p>
<p>
<%= f.label :content %><br />
<%= f.text_area :content %>
</p>
<p>
<%= f.submit 'Submit' %>
</p>
<% end %>
5) 之后我通过访问 /categories/my-category-permalink 收到错误消息
NoMethodError in Categories#show
undefined method `category_comments_path' for #<ActionView::Base:0x69a9254>
你能帮我理解我做错了什么吗?在原始截屏视频中,Ryan 使用嵌套关联通过 /categories/permalink/comments 访问评论,但我不需要。我想直接从我的多态对象中写评论。谢谢