Question

I created an application , which Users can create a Topic and other can post their comments about the topic. I can create a topic now and post.form work but when i post a comment i get

NoMethodError in Posts#create 

undefined method `each' for nil:NilClass

Extracted source (around line #2):

1: 
2: <% for topic in @topics do %>  
3:   <li><%=link_to topic.title, topic_path(topic) %></li>  
4: 
5:  <%= will_paginate @topics %>

My posts controller is :

class PostsController < ApplicationController
    before_filter :signed_in_user, only: [:create, :destroy]
  before_filter :correct_user, only: :destroy


    def create
        @post = current_user.posts.build(params[:post])
        if @post.save
            flash[:success] = "Konu oluşturuldu!"
                redirect_to topic_path(topic)
        else
            render 'static_pages/home'
        end
    end

  def destroy
    @post.destroy
    redirect_to root_path
  end
  private

    def correct_user
      @post = current_user.posts.find_by_id(params[:id])
      redirect_to root_path if @post.nil?
    end
end

When i create a post it redirects to localhost/posts … although i want it to stay in that topic . How can i correctly redirect?

Answer 1

I think it is better and a lot more concise to use @topics.each do instead of for topic in @topics do.

Basically, in your create action, it seems that you aren’t assigning @topics any value. So it will be nil. No defined method exists for trying to enumerate over nil, that is why ruby starts looking into the method_missing method of Nil class. Having not found any handling there, the following exception is generated.

I’d recommend you to assign some value to @topics