problems with creating new item in nested resource

I have nested resources as follows:

employer.rb

class Employer < ActiveRecord::Base

    has_many :listings

end

listing.rb

class Listing < ActiveRecord::Base

    belongs_to :employer

end

I built both using basic scaffold generator.

Everything seems to work except when I create a new listing for employer. The route is

new_employer_listing GET
/company/:employer_id/listings/new(.:format)
{:action=>"new", :controller=>"listings"}

When I navigate to the new listing url (company/employer_id/listings/new)

开发者_Go百科

I get:

NoMethodError in ListingsController#new
undefined method `listing' for #<Employer:0x102dd5e48>

Here is the listings_controller code for #new

  def new
    @employer = Employer.find_by_username(params[:employer_id])
    @listing = @employer.listing.new

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

Again, everything else works (show, edit, etc) -- I just can't get a new listing page to come up... Any help would be awesome.

Thanks!

//EDIT BELOW

  def create
    @employer = Employer.find_by_username(params[:employer_id])
    @listing = @employer.listings.new(params[:listing])

    respond_to do |format|
      if @listing.save
        format.html { redirect_to(@listing, :notice => 'Listing was successfully created.') }
        format.xml  { render :xml => @listing, :status => :created, :location => @listing }
      else
        format.html { render :action => "new" }
        format.xml  { render :xml => @listing.errors, :status => :unprocessable_entity }
      end
    end
  end

ERROR:

No route matches {:action=>"show", :controller=>"listings", :id=>#<Listing id: 20, job_title: "asd", location: nil, status: nil, industry: nil, years: nil, degree_type: nil, degree_field: nil, employer_id: 1, employers_id: nil, user_id: nil>}

---

In the Employer model you have added the has_many :listings association. But in your controller you call @employer.Listing.new. The thing that does not match here is Listing and listings.

You should instead do it like this:

@listing = @employer.listings.new(params[:listing)

Sidenotes:

Don't forget to call save on the @listing, otherwise it will not get saved.

I prefer to use build instead of new, that way the listing is available in the Employer association directly. Both methods valid though depending on how you use them.

---

The employer has_many listings, so you have to call @employer.listings, with an s.