我可以通过父模型进行多次关联吗？

Question

我构建了一个表单，让用户可以在我们的应用上设置店面。它工作正常。

我现在正在尝试添加将问题与产品相关联的功能。并非每个问题都适用于每种产品。例如，如果一家店面正在销售一件 T 恤，则适用的问题可能是“您的尺码是多少？”。

这是我的模型的基本图：

以下是我的模型类中的相关行：

class Organization < ActiveRecord::Base
  has_one :storefront
  has_many :questions
end

class Storefront < ActiveRecord::Base
  belongs_to :organization
  has_many :questions, through: :organizations
  has_many :products, class_name: Product::Base, dependent: :destroy
end

class Product::Base < ActiveRecord::Base
  belongs_to :storefront
  has_many :product_question_applicabilities
end

class ProductQuestionApplicability < ActiveRecord::Base
  belongs_to :product,  inverse_of: :product_question_applicabilities
  belongs_to :question, inverse_of: :product_question_applicabilities
end

class Question < ActiveRecord::Base
  belongs_to :organization
  has_many :answers
end

我在设置表单以接受新问题模型的属性时遇到问题。

这是我的表单的样子（精简到相关行）：

<%= form_for @storefront, url: create_or_edit_storefront_path(@storefront) do |f| %>

  <%= f.fields_for :questions do |ff| %>
    <%= render 'question_fields', f: ff %>
  <% end %>
  <%= link_to_add_association 'add question', f, :questions, :class => "add-question new-thing flat-link" %>

<% end %>

这给了我一个错误“ActiveRecord::HasManyThroughAssociationNotFoundError in Storefronts#edit，找不到关联：模型店面中的组织”

我是否正确设置了模型以实现这一目标？

Answer 1

您需要将accepts_nested_attributes_for 添加到您的模型中

尝试改变

class Storefront < ActiveRecord::Base
  belongs_to :organization
  has_many :questions, through: :organizations
  has_many :products, class_name: Product::Base, dependent: :destroy
end

到

    class Storefront < ActiveRecord::Base
      belongs_to :organization
      has_many :questions, through: :organizations
      has_many :products, class_name: Product::Base, dependent: :destroy
    accepts_nested_attributes_for :questions
   end