Footable not loading

我正在使用Footable插件。它在控制台中显示一个错误："TypeError:无法读取未定义的属性'sort'"。

我使用了以下步骤，

1. 在GemFile 中添加了gem"脚踏导轨"

2. 在应用程序中.css:

    *= require_self
    *= require datepicker
    *= require datetimepicker
    *= require dataTables/jquery.dataTables.bootstrap
    *= require DT_bootstrap
    *= require bootstrap-wysihtml5
    *= require jquery.ui.datepicker
    *= require jquery.timepicker
    *= require footable-rails
    *= require_tree .
   

3. Application.js:

   //= require jquery
   //= require jquery_ujs
   //= require jquery.ui.datepicker
   //= require twitter/bootstrap
   //= require bootstrap-datepicker
   //= require bootstrap-datetimepicker
   //= require dataTables/jquery.dataTables
   //= require dataTables/jquery.dataTables.bootstrap
   //= require jquery.timepicker.js
   //= require rails.validations
   //= require rails.validations.custom
   //= require rails.validations.simple_form
   //= require bootstrap-wysihtml5
   //= require highcharts
   //= require exporting
   //= require footable-rails
   //= require_tree .
   

我做错了什么？