create.rb

  def create
    @device = Device.new(params[:device])
    @device.user = current_user

    # the respond to structure allows ajax to run
    # but falls back to normal html form processing if
    # javascript is disabled, I think
    @save_status = false
    @rendered_content = ""
    if @device.save
      @save_status = true
      @rendered_content = render_to_string(:action => :show, :layout => false)     
    else
      @rendered_content = render_to_string(:action => :new, :layout => false)     
    end

    binding.pry

    respond_to do |format|
      format.html { 
        if @save_status 
          render 'show'
        else
          render 'new'
        end
      }

      format.js # this will render the
    end #respond_to
  end #create


#create.js.erb
/* render the form response */
$('#content').html(Utility.htmlDecode("<%= escape_javascript(@rendered_content) %>"));