如何使用accepts_nested_attributes_for手動構建正確的嵌套表單？

Question

我正在嘗試出於測試目的手動構建表單字段。 我得到以下模型：

class Bedroom < ActiveRecord::Base
    has_many :booked_bedrooms
    has_many :bookings, :through => :booked_bedrooms
end

class Booking < ActiveRecord::Base
    has_many :booked_bedrooms
    has_many :bedrooms, :through => :booked_bedrooms
    accepts_nested_attributes_for :booked_bedrooms
end

class BookedBedroom < ActiveRecord::Base
    belongs_to :booking
    belongs_to :bedroom
    # fields: bedroom_id, :booking_id
end

當我在控制台中嘗試以下操作時，預訂和關聯的booked_bedroom將被保存：

>> b = Booking.new({ :booked_bedrooms_attributes => { 0 => { :bedroom_id => 1  }  }  })
=> #<Booking id: nil, start_date: nil, end_date: nil, created_at: nil, updated_at: nil>
>> b.save
=> true
>> b.booked_bedrooms
=> [#<BookedBedroom id: 1, booking_id: 1, bedroom_id: 1, created_at: "2010-06-22 18:55:57", updated_at: "2010-06-22 18:55:57">]

所以我建立了這樣一個表格：

<% form_for @booking do |form| %>
<% for bedroom in @available_bedrooms %>

            <%= check_box_tag "booked_bedrooms_attributes[#{bedroom.id}][bedroom_id]", bedroom.id %> <%= bedroom.name %>  
            as
            <%= select_tag "booked_bedrooms_attributes[#{bedroom.id}][booking_type_id]", options_for_select(bedroom.booking_types.map {|p| [p.name, p.id]}) %>
<% end %>
<% end %>

但這是行不通的。 預訂已保存，但沒有新的BookedBedroom記錄。 有人可以告訴我怎么了嗎？

我知道我可以使用formtastic或某些fields_for，但出於演示目的，我想以硬編碼形式解決該問題。

Answer 1

我相信應該是這樣

<%= check_box_tag "booking[booked_bedrooms_attributes][][bedroom_id]",
   bedroom.id %>

<%= select_tag "booking[booked_bedrooms_attributes][][booking_type_id]",
   options_for_select(bedroom.booking_types.map {|p| [p.name, p.id]}) %>