Railscasts196, Rails 4, simple_form, JS, haml

As in Railscasts196, I have nested Attendances in Events, Events in Event_groups:

= simple_form_for(@event_group) do |f|
  = f.error_notification
  .form-inputs
    = f.input :name
  .form-actions
    = f.button :submit
  .h2 Events (not simple form)
  = f.fields_for :events do |p|
  = link_to_add_fields "Add field", p, :fields
    .field
      = p.label :starts_at
      = p.hidden_field :_destroy
      = link_to "[remove]", '#', class: "remove_fields"
        %p
        = p.fields_for :attendances do |f|
          .field
            = f.label :guest_id
            = f.text_field :guest_id
            = f.label :attendance_rate_id
            = f.text_field :attendance_rate_id

Event_groups.js:

$(document).on 'click', 'form .remove_fields', (event) ->
  $(this).prev('input[type=hidden]').val('1')
  $(this).closest('fieldset').hide()
  event.preventDefault()

$(document).on 'click', 'form .add_fields', (event) ->
  time = new Date().getTime()
  regexp = new RegExp($(this).data('id'), 'g')
  $(this).before($(this).data('fields').replace(regexp, time))
  event.preventDefault()

Application_helper.rb:

module ApplicationHelper
  def link_to_add_fields(name, f, association)
    new_object = f.object.send(association).klass.new
    id = new_object.object_id
    fields = f.fields_for(association, new_object, child_index: id) do |builder|
      render(association.to_s.singularize + "_fields", f: builder)
    end
    link_to(name, '#', class: "add_fields", data: {id: id, fields: fields.gsub("\n", "")})
  end
end

Now I can't make the jQuery work as in Railscasts for Delete and Add new. Something must be wrong with the link_to_add_fields & remove. Please help

Actually, nowadays there's a better way, using the cocoon gem.

It's very simple and I've had great success using it ;) hope you do too!