设计用户的嵌套表单

Question

我已经设计并运行，一切正常，我正在尝试..... let $audio_count := count($books/book[type = 'audio' and publisher = 'Seagypsy Publishing']) let $print_count := count($books/book[type = 'print' and publisher = 'Seagypsy Publishing']) ..... 模型accept_nested_attributes。我生成了一个名为degree的模型：

user

表单显示正确但没有数据保存到数据库中？在rails控制台中我跑了：

rails g model Degree university:string course:string level:string user:references
rake db:migrate

查看是否有任何数据被保存但我什么都没得到？

registration_controller.rb：

Degree.all

模型

class Users::RegistrationsController < Devise::RegistrationsController

  before_filter :configure_permitted_parameters, if: :devise_controller?

  protected

  def configure_permitted_parameters
    devise_parameter_sanitizer.for(:sign_up) { |u| u.permit(:email, :password, :password_confirmation,
       :fname, :mname, :lname, :twitterLink, :githubLink, :stackoverflowLink, :dribbleLink, :mediumLink, degree_attributes: [:university, :course, :level]) }

    #devise_parameter_sanitizer.for(:account_update) { |u| u.permit(:fname, :mname, :password, :current_password, :lname) }
  end

end

嵌套属性为的形式：

class Degree < ActiveRecord::Base
  belongs_to :user
end

----------------------------------

class User < ActiveRecord::Base
  # Include default devise modules. Others available are:
  # :confirmable, :lockable, :timeoutable and :omniauthable
  devise :database_authenticatable, :registerable,
         :recoverable, :rememberable, :trackable, :validatable

  has_many :degrees
  accepts_nested_attributes_for :degrees
end

degree_controller.rb

<h2>Sign up</h2>
<% resource.degrees.build %>
<%= form_for(resource, as: resource_name, url: registration_path(resource_name)) do |f| %>
  <%= devise_error_messages! %>

  <div class="field">
    <%= f.label :email %><br />
    <%= f.email_field :email, autofocus: true %>
  </div>

  <div class="field">
    <%= f.label :password %>
    <% if @minimum_password_length %>
    <em>(<%= @minimum_password_length %> characters minimum)</em>
    <% end %><br />
    <%= f.password_field :password, autocomplete: "off" %>
  </div>

  <div class="field">
    <%= f.label :password_confirmation %><br />
    <%= f.password_field :password_confirmation, autocomplete: "off" %>
  </div>

  <div class="field">
    <%= f.fields_for :degree do |degree_fields| %>
        <%= degree_fields.label :university %>
        <%= degree_fields.text_field :university %><br>

        <%= degree_fields.label :course %>
        <%= degree_fields.text_field :course %><br>

        <%= degree_fields.label :level %>
        <%= degree_fields.text_field :level %><br>
      <% end %>


    </div>
<div class="actions">
    <%= f.submit "Sign up" %>
  </div>
<% end %>