ben7th/vote — comment on commit 1afdf4f1b141836a3e42fef702e168045065dfb9
File: app/models/vote.rb line 10
By fushang318:

http://railscasts.com/episodes/196-nested-model-form-part-1

Nested Object Forms 使用起来很简洁，可能刚接触需要了解一下