rails_admin嵌套资源

Question

我有两个模型Sectors and Holds with has_many - belongs_to relation。

class Sector < ApplicationRecord
  has_many :holds, dependent: :destroy, inverse_of: :sector
end
class Hold < ApplicationRecord
  belongs_to :sector, inverse_of: :holds
end

我已创建自定义操作以显示每个扇区的嵌套保留：

class Holds < RailsAdmin::Config::Actions::Base
    RailsAdmin::Config::Actions.register(self)

    register_instance_option :member do
      true
    end

    register_instance_option :link_icon do
      'icon-user'
    end

    register_instance_option :visible? do
      bindings[:abstract_model].model.to_s == "Sector"
    end

    register_instance_option :controller do
      proc do

        @abstract_model = RailsAdmin::AbstractModel.new(Hold)
        @model_config = RailsAdmin::Config::Model.new(Hold)
        @model_config.include_fields :holder_name, :start_date, :end_date
        @objects = @object.holds

        render :index
      end
    end
  end

/sector

但是＆＃39;添加新的＆＃39;行动不存在：
/sector/23/holds 我如何添加＆＃39;添加新的＆＃39;行动并使用嵌套资源正常工作？