#9楼 @ywencn 我去看了，已经找到例子，多谢。见： https://github.com/edavis10/redmine/tree/master/extra/sample_plugin/ Rails强大！
http://guides.rubyonrails.org/engines.html Engines can be considered miniature applications that provide functionality to their host applications. A Rails application is actually just a “supercharged” engine, with the Rails::Application class inheriting from Rails::Engine. Therefore, engines and applications share common functionality but are at the same time two separate beasts. Engines and applications also share a common structure, as you’ll see throughout this guide.