ruby-on-rails - 在嵌套的 Rails 表单上创建多对多关系

Question

我正在尝试同时创建组、用户和成员资格(多对多关系)。人们可以在创建群组时将用户添加到群组中，然后我希望它可以路由到包含所有成员的群组 View 。我可以让要创建的用户和当前用户的成员资格保存到数据库中。但是，我正在努力获取新创建的用户对象的 ID 以保存新成员资格。

组.rb

class Group < ActiveRecord::Base
  has_many :memberships
  has_many :users, :through => :memberships
  has_many :users

  accepts_nested_attributes_for :users, :reject_if => lambda { |a| a[:name].blank? or a[:number].blank? }
end

成员(member).rb

class Membership < ActiveRecord::Base
  belongs_to :groups
  belongs_to :users
end

用户.rb

class User < ActiveRecord::Base
  has_many :memberships
  has_many :groups, :through => :memberships
  belongs_to :group
end

groups_controller.rb

class GroupsController < ApplicationController

  def show
    @group = Group.find(params[:id])    
    respond_to do |format|
      format.html
    end
  end

  def new
    @group = Group.new

    3.times { @group.users.build }
  end

  def create 
    @group = Group.new(params[:group]) 
    @group.memberships.build(:user_id => current_user.id)
    logger.info @group.users

    @group.users.each do |x|
      @group.memberships.build(:user_id => x.id )
    end

    respond_to do |format|
      if @group.save
        format.html { redirect_to(@group, :notice => 'Success!') }
      else
        format.html { render :action => "new" }
      end
    end

  end
end

我的表单如下所示:

创建者:

views/groups/new.html.rb

<h1>New group</h1>

<%= form_for(@group) do |form| %>
<fieldset>
  <legend>Create a new group</legend>
  <%= render 'shared/group_error_messages', :object => form.object %>  
  <div class="clearfix">
    <%= form.label :group_name %>
    <div class="input">
      <%= form.text_field :group_name %>
    </div>
  </div>

  <div id="users">
    <div class="user">
      <%= form.fields_for :users, :url => {:action => 'new', :controller => 'users', :registered => false}, do |user_form| %>
      <%= render 'user', :user => user_form %>
      <% end %>
    </div>
  </div>
</div>

<div class="actions">
  <%= form.submit :value => 'Create your group', :class => 'btn success'%>
</div>
</fieldset>
<% end %>

views/groups/_user.html.rb

<div class="clearfix">
  <%= user.label :name %>
  <div class="input">
    <%= user.text_field :name %>
  </div>
</div>
<div class="clearfix">
  <%= user.label :number %>  
  <div class="input">
    <%= user.text_field :number %>
  </div>

</div>
<div class="clearfix" style="display:none">
  <%= user.label :password %>  
  <div class="input">
    <%= user.password_field :password, :value => newpass(6) %><!-- todo: fix this horrible hack -->
  </div>
</div>
<div class="clearfix" style="display:none">
  <%= user.label :registered %>  
  <div class="input">
    <%= user.text_field :registered, :value => false %> <!-- todo: fix this horrible hack -->
  </div>
</div>
<div class="clearfix" style="display:">
  <%= user.label :id %>  
  <div class="input">
    <%= user.text_field :id %> <!-- todo: fix this horrible hack -->
  </div>
</div>

所以我的主要愿望是获取这段代码以在创建用户 ID 时找到它们，然后使用这些 ID 在组和用户之间建立成员资格。

提前非常感谢非常非常 :)

Answer 1

我觉得

has_many :users, :through => :memberships
has_many :users

是错误的，你不能有两个或更多同名关联。

尝试去做

has_many :users, :through => :memberships
has_many :members, :class_name => 'User', :foreign_key => :user_id

并对 View 和 Controller 进行相应的更改。喜欢

form.fields_for : members