Question

I am writing an application , which User can create Topics and others can make posts on that topic.

I am stuck with this error :

No route matches {:action=>"show", :controller=>"topics", :id=>nil}

my route.rb :

MyPedia2::Application.routes.draw do
    resources :users

    resources :sessions, only: [:new, :create, :destroy]
    resources :topics, only: [:show, :create, :destroy] 

  match '/signup',  to: 'users#new'
  match '/signin',  to: 'sessions#new'
  match '/signout', to: 'sessions#destroy', via: :delete

    root to: 'static_pages#home'

    match '/topics/:id', to: 'topics#show'

my rake route shows :

   topics POST   /topics(.:format)         topics#create
      topic GET    /topics/:id(.:format)     topics#show
            DELETE /topics/:id(.:format)     topics#destroy
    root        /                         static_pages#home
               /topics/:id(.:format)     topics#show

and my topics controller is:

# encoding: utf-8

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


  def show
        @topic = Topic.find_by_id(params[:id])
  end

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

  def destroy
    @topic.destroy
    redirect_to root_path
  end
  private

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

Is there a fix for this ?
EDIT : I found that _topics.html.erb fails
I found what breakes the code :

<% for topic in @topics do %>  
  <li><%=link_to topic.title, topic_path(@topic) %></li>  

 <%= will_paginate @topics %>
<% end %>  

topic_path(@topic] part is wrong. How can i make it to use id?

Answer 1

It’s not working because your collection is ‘@topics’, and each element is ‘topic’, not ‘@topic’. But you’re close. Try this:

<li><%=link_to topic.title, topic_path(topic) %></li>