Question

I am not sure how to proper create a rails form with nested form. I have followed many tutorial but becoming more confused has in what should it be, singular plurials, controller… Here my models

model/event.rb

  attr_accessible :description :title, :tag_ids, :locations_attributes
  has_many :location
  accepts_nested_attributes_for :location, :allow_destroy => true

model/location.rb

  attr_accessible :address, :customer_id, :event_id, :latitude, :longitude
  belongs_to :customer
  belongs_to :event

controller.rb

  def new
    @event = Event.new
    ...
  def create
    @event = Event.new(params[:event])
    ...

view form.html.erb

<%= form_for(@event) do |f| %>
  <%= f.fields_for :locations do |e| %>
    <%= e.text_field :longitude %>
    <%= e.text_field :latitude %>
  <% end %>
  ...
<% end %>

error

Can't mass-assign protected attributes: locations

params send

 "locations"=>{"longitude"=>"45.6666",
 "latitude"=>"47.44444665"},

Either my relationship are wrong because fields_for doesn’t support it, either my controller is not proper, or either rails is just not a great language, or i don’t understand it anymore.

Answer 1

You.re nearly there…

event.rb – locations NOT location

attr_accessible :description :title, :tag_ids, :locations_attributes
has_many :locations
accepts_nested_attributes_for :locations, :allow_destroy => true

Should do it I think

edit

And as Valery Kvon says, you need to add

@event.locations.build

to your controller