Link 在活动管理员中自定义多态关联操作

Question

我正在与 Active Admin 合作。目前，我有一个索引页面，允许我查看所有已被用户标记的资源。鉴于存在各种类型的资源，我的 Flagged class 和各种资源表之间存在多态关系。

在我的索引页面中，在 Active Admin 上，我希望能够 link 到属于特定资源类型的适当显示页面。

我的所有代码都可以正常工作，但我不喜欢我提出的解决方案。

如何改进我当前的解决方案，这样我就不必写一个笨拙的条件？

型号

class Flag < ActiveRecord::Base
  #create relationships with user and flag model
  belongs_to :flaggable, polymorphic: true
end

class MilitaryResource < ActiveRecord::Base
  has_many :flags, as: :flaggable, :dependent => :destroy  
end

class DistrictResource < ActiveRecord::Base
  has_many :flags, as: :flaggable, :dependent => :destroy  
end

class SchoolResource < ActiveRecord::Base
  has_many :flags, as: :flaggable, :dependent => :destroy  
end

ActiveAdmin

ActiveAdmin.register Flag do

  #parameters permitted to create military resources
  permit_params :id, :user_id, :flaggable_id, :flaggable_type, :message, :created_at

  #index page
  index do
    column :flaggable_type

    ###Current Solution
    column "Flagged Resource" do |site|
      if site.flaggable_type == "MilitaryResource"

        link_to site.flaggable.name, :controller => "military_resources", :action => "show", :id => "#{site.flaggable_id}".html_safe

      elsif site.flaggable_type == "SchoolResource"

        link_to site.flaggable.name, :controller => "school_resources", :action => "show", :id => "#{site.flaggable_id}".html_safe

      elsif site.flaggable_type == "DistrictResource"

        link_to site.flaggable.name, :controller => "district_resources", :action => "show", :id => "#{site.flaggable_id}".html_safe

      end
    end

    column :message
    actions
  end

Answer 1

你可以这样做来避免条件：

column "Flagged Resource" do |site|
  link_to site.flaggable.name, 
          :controller => site.flaggable_type.underscore.pluralize, 
          :action => "show",
          :id => "#{site.flaggable_id}"
    .html_safe
end

Link 在活动管理员中自定义多态关联操作

Link to custom polymorphic association action in active admin

ruby

polymorphism

ruby-on-rails

polymorphic-associations

activeadmin