Calling two methods from one controller in nested model form - ruby-on-rails-3

Question

Through other posts on SO I've learned that my sign-up process using a nested model form is flawed in that I create a new User, then redirect to create its Profile. Here is the process:
user = User.new
user.email = ...
user.password = ...
user.profile = Profile.new
user.profile.first_name = ...
...
user.profile.save
user.save
It seems as if one solution is to initiate the profile method from within the UsersController create(?) action, so that I POST to both models(?) then redirect to a page with a form to fill out the rest of the profile.
But I'm not entirely sure how to do that, as I am new to programming/Rails. So can anyone give me guidance on how to introduce the Profile method within the UsersController? I gave it a go but don't think it's correct. Code for both Users/ProfilesController below:
User:
def new
#user = User.new
#user.profile = Profile.new
end
def index
#user = User.all
end
def create
#user = User.new(params[:user])
if #user.profile.save
redirect_to profile_new_path, :notice => 'User successfully added.'
else
render :action => 'new'
end
end
Profile:
def new
#user.profile = Profile.new
end
def create
#profile = Profile.new(params[:profile])
if #profile.save
redirect_to profile_path, :notice => 'User successfully added.'
else
render :action => 'new'
end
end
Routes.rb:
match '/signup' => 'profiles#new', :as => "signup"
get "signup" => "profiles#new", :as => "signup"
root :to => 'users#new'
resources :users
resources :profiles
My nested model form (the relevant parts):
<%= form_for(:user, :url => { :action => :create }, :html => {:id => 'homepage'}) do |f| %>
<%= f.text_field :email, :size=> 13, :id => "user[email]" %>
<%= f.fields_for :profile do |f| %>
<% end%>
<% end %>
If anyone could help me I'd greatly appreciate it.

Answer 1

You should have something like this in your models:
class User < ActiveRecord::Base
has_one :profile
accepts_nested_attributes_for :profile
end
class Profile < ActiveRecord::Base
belongs_to :user
end
...of course all backed up with proper migrations. Then while building up a form you can use fields_for helper. Here is slightly modified example from docs:
<%= form_for #user do |user_form| %>
Email: <%= user_form.text_field :email %>
<%= user_form.fields_for :profile do |profile_fields| %>
First Name: <%= profile_fields.text_field :first_name %>
<% end %>
<% end %>
And update your user and his profile in the controller in one go, thanks to accepts_nested_attributes_for :profile declaration in your model.