My overall use case:

I have a Listing model that has many images. The Listing detail page lists all the fields that can be updated inline (through ajax).

I want to be able to use the same view for both update listing and create new listing.

My listing controller looks as follows:

 def detail 
     @listing = Listing.find(params[:id])  
     @image = Image.new #should this link somewhere else?

     respond_to do |format| 
         format.html # show.html.erb  
         format.xml { render :xml => @listing } 
      end 
 end 


  def create
      # create a new listing and save it immediately. Assign it to guest, with a status of "draft"
      @listing = Listing.new(:price_id => 1)  # Default price id
      # save it to db
      # TODO add validation that it has to have a price ID, on record creation. So the view doesn't break.
      @listing.save
      @image = Image.new

      # redirect_to "/listings/detail/@listing.id" #this didn't work

      respond_to do |format| 
          format.html # show.html.erb  
          format.xml { render :xml => @listing } 
      end
 end 

The PROBLEM
I'm using a partial that shows the same form for the create view and the detail view.

This works perfectly except for one thing: When I pull up
http://0.0.0.0:3000/listings/detail/7, it works perfectly.

When I pull up
http://0.0.0.0:3000/listings/new, I get the following error:

Showing /Applications/MAMP/htdocs/rails_testing/feedbackd/app/views/listings/_edit_form.html.erb where line #100 raised:

No route matches {:action=>"show", :controller=>"images"} Extracted source (around line #100):

97: <!-- Form for new images -->
98: <div class="span-20 append-bottom">
99: <!-- <%# form_for :image, @image, :url => image_path, :html => { :multipart => true } do |f| %> -->
100: <%= form_for @image, :url => image_path, :html => { :multipart => true } do |f| %>
101:     <%= f.text_field :description %><br />
102:  <%= f.file_field :photo %>
103:  <%= submit_tag "Upload" %>

What I think the issue is: When I upload a new image (I'm using Paperclip), it requires the listing_id to create the image record. Since the listing_id isn't passed in with listings/new it can't find the listing_id. How can I pass in the id? Via a redirect? What's the best way to solve this? Thank you.