Question

I’m following the Backbone Railscasts and the sortable list Railscast, but I’ve a problem to get them together.

Backbone template:

<ul id="faqs" data-update-url="/api/faqs/sort">
</ul>

Backbone view:

render: ->
  $(@el).html(@template())
  @collection.each(@appendFaqs)

  $("#faqs").sortable
    axis: 'y'
    update: ->
      $.post($(this).data('update-url'), $(this).sortable('serialize'))

Rails Controller:

class FaqsController < ApplicationController

  def sort
   params[:faq].each_with_index do |id, index|
      Faq.update_all({position: index+1}, {id: id})
    end
    render nothing: true
  end

OUTPUT:

Started POST "/api/faqs/sort" for 127.0.0.1 at 2012-06-03 01:17:20 +0200
Processing by FaqsController#sort as */*
Completed 500 Internal Server Error in 1ms

NoMethodError (undefined method `each_with_index' for nil:NilClass):
  app/controllers/faqs_controller.rb:28:in `sort'

I understand that my params are nil. But I don’t understand why in the railscast code project which I’ve clone it is working.

I saw that I should overwrite the toJSON method (backbone), should I go in this way ?

To be honest, I’m out of control.

Railscasts used:

• http://railscasts.com/episodes/323-backbone-on-rails-part-1
• http://railscasts.com/episodes/147-sortable-lists-revised

Answer 1

You need to set an id on your <li> elements:

<li id="faq_1">...</li>
<li id="faq_2">...</li>
<li id="faq_3">...</li>
<li id="faq_4">...</li>

You should read this to a better understanding of the serialize method.