```ruby
module ActiveAdmin
  module Reorderable
    module TableMethods

      def reorder_column
        column '', :class => 'reorder-handle-col' do |resource|
          reorder_handle_for(resource)
        end
      end

      private

      def reorder_handle_for(resource)
        url = [active_admin_config.route_instance_path(resource), :reorder].join('/')
        span(reorder_handle_content, :class => 'reorder-handle', 'data-reorder-url' => url)
      end

      def reorder_handle_content
        '&equiv;&equiv;'.html_safe
      end

    end

    ::ActiveAdmin::Views::TableFor.send(:include, TableMethods)
  end
end

```

Fix URL building for nested resources
user
```ruby
module ActiveAdmin
  module Reorderable
    module TableMethods

      def reorder_column
        column '', :class => 'reorder-handle-col' do |resource|
          reorder_handle_for(resource)
        end
      end

      private

      def reorder_handle_for(resource)
        url = [
          active_admin_namespace.resource_for(resource.class).route_instance_path(resource),
          :reorder
        ].join('/')

        span(reorder_handle_content, :class => 'reorder-handle', 'data-reorder-url' => url)
      end

      def reorder_handle_content
        '&equiv;&equiv;'.html_safe
      end

    end

    ::ActiveAdmin::Views::TableFor.send(:include, TableMethods)
  end
end

```
assistant