Rails：将新的子对象占位符（构建）传递给父视图

Question

我有 2 类对象...Magician has_many Rabbits 和 Rabbit owns_to Magician。

查看魔术师 (show.html) 时，我想列出所有关联的兔子，然后使用一些带有提交按钮的空白字段来添加新兔子。为此，我在魔术师的 show 方法（如下）中构建一只新兔子（与当前魔术师关联）。

Edit2：找到了使其工作的方法，但不确定它是否是“Rails 方式”？

查看内嵌评论（如下）： 如果我在 Magician 的 show 方法中构建兔子，那么当渲染 show 时，一个空（且无效）的兔子会在显示新的兔子表单字段之前结束列表。

如果我在视图本身中构建它，那么一切都会正常工作。正确渲染。我被引导相信我们不应该在视图中做这种类型的事情...如果是这样，解决这个问题的正确方法是什么？

#/app/controllers/magicians_controller.rb
class MagiciansController < ApplicationController
  respond_to :html, :json

  def show
    @magician = Magician.find(params[:id])
    @rabbit = @magician.rabbits.build  # <=== build here and empty rabbit gets 
       # included in @magician.rabbits when they're rendered...
       # but is NOT included in @magician.rabbits.count for some reason?!?!?
    respond_with(@magician)
  end
...
end

#view/magicians/show.html.haml
%p
  %b Name:
  = @magician.name

%h2 Rabbits
= "There are #{pluralize(@magician.rabbits.count, "rabbit")}"
= render @magician.rabbits, :target => @magician

%h2 Add a rabbit:
- @rabbit = @clown.rabbits.build -# <=== build here and everything SEEMS to work
= render :partial =>"rabbits/form", :locals => { :parent => @magician, :foreign_key => :magician_id, :flash => flash } 

Edit1 ：根据请求添加从部分生成的html：

  <p>
    <b>Rabbit:</b>

    <b>Color:</b>

    |
    <b>ID:</b>

    <a href="/magicians/2/rabbits" data-confirm="Sure? A bunny will die" data-method="delete" rel="nofollow">Kill Rabbit</a>
  </p>

我想您可能想查看生成此内容的部分：

%p
  %b Rabbit:
  = rabbit.name

  %b Color: 
  = rabbit.color
  |
  %b ID:
  = rabbit.id
  = link_to("Kill Rabbit", [target, rabbit], :method => :delete, :confirm => "Sure? A bunny will die")