在我的Rails 3应用程序中,我有以下简单的关系结构:
class Rollout < ActiveRecord::Base
has_many :items, :through => :rollout_items
end
class RolloutItem < ActiveRecord::Base
belongs_to :rollout
belongs_to :item
end
class Item < ActiveRecord::Base
has_many :rollouts, :through => :rollout_items
end
控制器:
def new
@rollout = Rollout.new
end
我使用以下格式获得上述错误:
<%= simple_form_for @rollout do |f| %>
<%= f.association :items %>
<% end %>
答案 0 :(得分:6)
Rollout
和RolloutItem
之间缺少关系:
class Rollout < ActiveRecord::Base
has_many :rollout_items # This.
has_many :items, :through => :rollout_items
end
Item
同样如此。