ruby-on-rails – Mongoid :: Errors :: MixedRelations save

class Interest
  include Mongoid::Document

  has_many :user_hobby
end

class UserHobby
 include Mongoid::Document
  field :contacts,:type => Array

  belongs_to :interest,:foreign_key => "interest",inverse_of: nil
  belongs_to :interest,:foreign_key => "related_interests",inverse_of: nil
  embedded_in :user
end

class User
 include Mongoid::Document
 embeds_many :user_hobby
end

我必须在user和user_hobby之间添加嵌入式关系,但之后(在我的测试中)
当我想保存兴趣时,我有这个错误：

Mongoid::Errors::MixedRelations: Referencing a(n) UserHobby document from the Interest document via a relational association is not allowed since the UserHobby is embedded.

我看了这个话题但是Mongoid::Errors::MixedRelations也没帮我

谢谢.