sign up and create new object at the same time - ruby-on-rails

Question

i'm new in Ruby on Rails.
I was trying to register a new user with devise and at the same time, create a new Company object. The association between them : User belongs to Company. Company has many users. I tried to make it based on this link : http://railscasts.com/episodes/196-nested-model-form-part-1?view=asciicast, but it didnt work. it said : "undefined method for Company", which is Company doesnt have email attribute.
and in sign up form, i only put email attribute for user
<div class="title"><%= t('.signup') %></div>
<%= form_for(resource, :as => resource_name, :url => registration_path(resource_name)) do |f| %>
<%= devise_error_messages! %>
<div class="control-group"><%= f.label :email, t('.email') %>
<%= f.email_field :email %></div>
<div class="control-group"><%= f.label :password, t('.password') %>
<%= f.password_field :password %></div>
<div class="control-group"><%= f.label :password_confirmation, t('.password_confirmation') %>
<%= f.password_field :password_confirmation %></div>
<%= f.fields_for :company_attributes do |f_company| %>
<div class="control-group"><%= f_company.label :name, t('.company_name') %>
<%= f_company.text_field :name %></div>
<% end %>
<div class="buttons"><%= f.submit t('.signup'), class:"btn btn-primary" %><br>
<%= render "links" %></div>
<% end %>
updated
Company controller :
class CompaniesController < Devise::RegistrationsController
def new
#company = Company.new
#user = #company.users.build
end
def create
#company = Company.new(params[:company])
#user = User.create(params[:user].merge(company_id:company.id))
if #company.save
redirect_to "/"
else
render 'users/sign_up'
end
end
end
User Controller :
def new
#user = User.new
end
def create
#user = User.new(params[:user])
if #user.save
redirect_to users_path
else
render 'users/new'
end
end
I would really appreciate any idea and any help. Thanks in advance

Answer 1

In your case, since you are only interested in receiving the company_name I'd simplify it and submit the company_name via a text_field_tag.
In other words, I would replace:
<%= f.fields_for :company_attributes do |f_company| %>
<div class="control-group"><%= f_company.label :name, t('.company_name') %>
<%= f_company.text_field :name %></div>
<% end %>
With this
<%= text_field_tag 'company_name', {placeholder:"Enter here the name of your company",class:"form-control"} %>
This would submit the name to the UsersController, and you could access it with params[:company_name] so the controller would look like this:
Users controller:
def new
#user = User.new
end
def create
#user = User.create(params[:user])
#Create a company via 'user<->company' association using 'company_name'
#company= #user.company.create(name: params[:company_name])
if #user.save
redirect_to users_path
else
render 'users/new'
end
end