Adding my comments to the index view...Ruby on Rails - ruby-on-rails

Question

Ok...I am new to rails so this may be a stupid question but need help. I just watched and implemented Ryan Bates screencaset about setting up a blog. You can see it here http://media.rubyonrails.org/video/rails_blog_2.mov. Here is the skinny:
Two tables: Posts and Comments. Everything works great including the addition of comments via AJAX. The default development of this blog gives you the index.html.erb view where you can view all the posts
def index
#posts = Post.all
respond_to do |format|
format.html # index.html.erb
format.xml { render :xml => #posts }
format.json { render :json => #posts }
format.atom
end
end
The comments are only viewed via the show.html.erb page and is displayed via this code in that file:
<%= render :partial => #post %>
<p>
<%= link_to 'Edit', edit_post_path(#post) %> |
<%= link_to 'Destroy', #post, :method => :delete, :confirm => "Are You Sure" %> |
<%= link_to 'See All Posts', posts_path %>
</p>
<h2>Comments</h2>
<div id="comments">
<%= render :partial => #post.comments %>
</div>
<% remote_form_for [#post, Comment.new] do |f| %>
<p>
<%= f.label :body, "New Comment" %><br/>
<%= f.text_area :body %>
</p>
<p><%= f.submit "Add Comment"%></p>
<% end %>
What I am trying to do is to get similair representation of the comments functionality to exist in the index.html.erb view (which I will hide with javascript). Which currently just looks like this:
<h1>Listing posts</h1>
<%= render :partial => #posts %>
<%= link_to 'New post', new_post_path %>
My initial thought was just to put this exact same code that is in the show.html.erb file in the index.html.erb file but that doesn't work. I have tried a bunch of things here but I am not familiar enough with Rails (or coding for that matter) yet to do this in a timely manner. I get two main errors. Either that I passed a nil.comments error or an undefined object/method (can't remember).
My question is what do I need to included in the post_controller, the comments_controller and the index.html.erb file to accomplish this. To be complete I have included the code in each below.
POSTS_CONTROLLER
class PostsController < ApplicationController
before_filter :authenticate, :except => [:index, :show]
# GET /posts
# GET /posts.xml
def index
#posts = Post.all
respond_to do |format|
format.html # index.html.erb
format.xml { render :xml => #posts }
format.json { render :json => #posts }
format.atom
end
end
# GET /posts/1
# GET /posts/1.xml
def show
#post = Post.find(params[:id])
respond_to do |format|
format.html # show.html.erb
format.xml { render :xml => #post }
end
end
# GET /posts/new
# GET /posts/new.xml
def new
#post = Post.new
respond_to do |format|
format.html # new.html.erb
format.xml { render :xml => #post }
end
end
# GET /posts/1/edit
def edit
#post = Post.find(params[:id])
end
# POST /posts
# POST /posts.xml
def create
#post = Post.new(params[:post])
respond_to do |format|
if #post.save
flash[:notice] = 'Post was successfully created.'
format.html { redirect_to(#post) }
format.xml { render :xml => #post, :status => :created, :location => #post }
else
format.html { render :action => "new" }
format.xml { render :xml => #post.errors, :status => :unprocessable_entity }
end
end
end
# PUT /posts/1
# PUT /posts/1.xml
def update
#post = Post.find(params[:id])
respond_to do |format|
if #post.update_attributes(params[:post])
flash[:notice] = 'Post was successfully updated.'
format.html { redirect_to(#post) }
format.xml { head :ok }
else
format.html { render :action => "edit" }
format.xml { render :xml => #post.errors, :status => :unprocessable_entity }
end
end
end
# DELETE /posts/1
# DELETE /posts/1.xml
def destroy
#post = Post.find(params[:id])
#post.destroy
respond_to do |format|
format.html { redirect_to(posts_url) }
format.xml { head :ok }
end
end
private
def authenticate
authenticate_or_request_with_http_basic do |name, password|
name == "admin" && password == "secret"
end
end
end
COMMENTS_CONTROLLER
class CommentsController < ApplicationController
def create
#post = Post.find(params[:post_id])
#comment = #post.comments.create!(params[:comment])
respond_to do |format|
format.html { redirect_to #post}
format.js
end
end
end
INDEX.HTML.ERB
<h1>Listing posts</h1>
<%= render :partial => #posts %>
<%= link_to 'New post', new_post_path %>

Answer 1

Here's one simple solution. Step 1, edit your index action to include all the comments belonging to each post.
def index
#posts = Post.all(:include => :comments)
respond_to do |format|
format.html # index.html.erb
format.xml { render :xml => #posts }
format.json { render :json => #posts }
format.atom
end
end
Step 2, edit your index view to display each post, followed by its comments:
<h1>Listing posts</h1>
<% #posts.each do |post| %>
<%= render :partial => post %>
<%= render :partial => post.comments %>
<% end %>
<%= link_to 'New post', new_post_path %>
Edit: I'm not 100% sure of the best way to include the comment creation form also. What I'd try first is this (in index.html.erb):
Try changing your index view to:
<h1>Listing posts</h1>
<% #posts.each do |post| %>
<%= render :partial => post %>
<%= render :partial => post.comments %>
<% remote_form_for [post, Comment.new] do |f| %>
<p>
<%= f.label :body, "New Comment" %><br/>
<%= f.text_area :body %>
</p>
<p><%= f.submit "Add Comment"%></p>
<% end %>
<% end %>
<%= link_to 'New post', new_post_path %>
This should render the "New comment" form for a given post under the comments for that post, but I'm not sure (without actually trying it out) whether the form submission AJAX will successfully update and refresh the index page.