Question

这里我有3个型号 1.category 2.post 3.用户

帖子belongs_to类别而且发布了belongs_to用户，当我尝试渲染一个新的帖子视图时，它说“未定义的方法`model_name'为nil：NilClass”

这是代码

的routes.rb

resources :categories do
  resources :posts
end

模型

模型/ post.rb

class Post < ActiveRecord::Base
  belongs_to :postable, polymorphic: true

模型/ users.rb的

class User < ActiveRecord::Base
  devise :database_authenticatable, :registerable,
         :recoverable, :rememberable, :trackable, :validatable
  has_many :posts, as: :postable

模型/ categories.rb

class Category < ActiveRecord::Base
  has_many :posts, as: :postable
end

控制器

控制器/ posts_controller.rb

class PostsController < ApplicationController
  before_action :find_category
  before_action :find_post, only: [:show, :edit, :update, :destroy, :upvote, :downvote]
  before_action :authenticate_user!, except: [:index, :show]

def index
    @posts = category.post
end

def show
  @post = category.posts.find(params[:id])
end

def new
    @post = current_user.posts.build
end

def create
    @post = current_user.posts.build(post_params)
        render 'new'
    end
end

private

    def post_params
        params.require(:post).permit(:tittle, :content, :map, :bootsy_image_gallery_id, {postmages: []})
    end

    def find_post
        @post = Post.find(params[:id])
    end

    def find_category
        @category = Category.find(params[:post_id])
    end
  end
end

我需要在类别显示页面中有一个创建帖子链接，但结果永远不对。

查看

视图/帖/ new.html.erb

<%= simple_form_for @post do |f| %>
  <% if @post && @post.errors.any? %>
    <div class="alert alert-danger">
      <p><%= pluralize(@post.errors.count, "error") %> prohibited this post from being saved:</p>
      <ul>
      <% @post.errors.full_messages.each do |message| %>
        <li><%= message %></li>
      <% end %>
      </ul>
    </div>
  <% end %>
  <%= f.input :title %>
  <%= f.input :content %>
  <%= f.button :submit %>
<% end %>

我不确定导致问题的原因是“未定义的方法`model_name'为nil：NilClass”，而我试图发布新帖子

获取“未定义的方法`model_name'为nil：NilClass”错误

0 个答案: