Assign foreign key in ruby rails

Question

I am new to rails and I am having a hard time assigning the foreign key user_id to user_profile .

When a user creates an account it is saved to the database, then they are taken to create a profile. The user can create the profile and the profile is saved to the database. I used to have

<tr>
    <th><%= f.label(:user_id, "User ID") %></th>
    <td><%= f.text_field(:user_id) %></td>
  </tr>

assign on the user profile form, and it worked, user.user_profile showed there was a relationship. but I don't want a user to have to/be able to choose the user_id they are creating a profile for. I can't figure out how to assign the user_id to the user_profile. in the controller for user_profiles I have

def new
    @user = User.find(session[:user_id])
    @user_profile = UserProfile.new({:user_id => @user.id})

  end

and for the new page for user_profiles I have

<%= form_for(:user_profiles, :url => {:action => 'create', :user_id => @user.id}) do |f| %>
    <%= render(:partial => "form", :locals => {:f => f}) %>
<% end %>

any ideas? Thank You

Answer 1

Assuming you are on rails 4, you just need to add into User.rb

has_many :user_profiles, dependent: :destroy

and into user_profile.rb

belongs_to :user
validates :user_id, presence: true

user_profiles_controller.rb

def create
   @user_profile = current_user.user_profiles.build(user_profile_params)
   ....
end

private

  def user_profile_params
    params.require(:user_profile).permit(:param1, :param2)
  end

form view

<%= form_for(@user_profile) do |f| %>
    <%= render(:partial => "form", :locals => {:f => f}) %>
<% end %>