不知道如何申報此的has_many態關聯

Question

我有一個用戶模式，即可能有許多活動（我跟蹤的一些我的用戶執行的操作，用於統計目的）

class User < ActiveRecord::Base 
    has_many :activities 
    has_many :histories,:through => :activities # ? 
end 

class Activity < ActiveRecord::Base 
    belongs_to :user 
    belongs_to :history, :polymorphic => true 
end 

class BrowsingHistory < ActiveRecord::Base 
    has_many :activities,:as => :histories 
end 

class LoginHistory < ActiveRecord::Base 
    has_many :activities,:as => :histories 
end 

... 

Activity類有一個history_type:string，一個history_id:integer和一個user_id:integer，我希望它能夠容納BrowsingHistory或LoginHistory對象。

我工作很少與多態關聯，從我到目前爲止，我不斷收到錯誤：ActiveRecord::HasManyThroughAssociationPolymorphicSourceError:Cannot have a has_many :through association 'User#histories' on the polymorphic object 'History#history'。我閱讀了有關這個主題的一些相關問題，但我無法找出解決方案。

編輯：我想我知道了（控制檯測試似乎工作），請你確認一下嗎？

class User < ActiveRecord::Base 
    has_many :activities 
    has_many :login_histories,:through => :activities,:source => :history,:source_type => "LoginHistory" 
end 

class Activity < ActiveRecord::Base 
    belongs_to :user 
    belongs_to :history, :polymorphic => true 
end 

class BrowsingHistory < ActiveRecord::Base 
    has_many :activities,:as => :history 
    has_many :users,:through => :activities 
end 

class LoginHistory < ActiveRecord::Base 
    has_many :activities,:as => :history 
    has_many :users,:through => :activities 
end 

Answer 1

這工作得很好：

class User < ActiveRecord::Base 
    has_many :activities 
    has_many :login_histories,:through => :activities,:source => :history,:source_type => "LoginHistory" 
end 

class Activity < ActiveRecord::Base 
    belongs_to :user 
    belongs_to :history, :polymorphic => true 
end 

class BrowsingHistory < ActiveRecord::Base 
    has_many :activities,:as => :history 
    has_many :users,:through => :activities 
end 

class LoginHistory < ActiveRecord::Base 
    has_many :activities,:as => :history 
    has_many :users,:through => :activities 
end