给定以下模型、关系和编辑表格
class User < ActiveRecord::Base
has_many :relationships, foreign_key: "follower_id", dependent: :destroy
has_many :followed_users, through: :relationships, source: :followed
has_many :reverse_relationships, foreign_key: "followed_id",
class_name: "Relationship",
dependent: :destroy
has_many :followers, through: :reverse_relationships, source: :follower
end
<%= form_for(@topic) do |f| %>
<%= render 'shared/error_messages', object: f.object %>
<%= f.label :name %>
<%= f.text_field :name %>
<%= f.label :Followers %>
<%= f.fields_for :relationships do |builder| %>
<%= f.collection_select :follower_id, User.all( order: "name"), :id, :name, include_blank: true %>
<% end %>
<%= f.submit "Save Changes" %></div>
<% end %>
class Relationship < ActiveRecord::Base
attr_accessible :followed_id
belongs_to :follower, class_name: "User"
belongs_to :followed, class_name: "User"
validates :follower_id, presence: true
validates :followed_id, presence: true
end
在这种情况下,关系字段出现在给定用户的编辑表单中。因此,他们可以管理所有的追随者。但问题是,在编辑页面上,用户按添加顺序显示。尽管 :relationships 关联只有一个 id,但有没有办法对它们进行排序,使它们按名称的字母顺序显示?