嵌套属性的表单助手 has_many 到 rails 4

Question

我有 3 个模型 has_many 通过关联：

class Spot < ActiveRecord::Base
  has_many :seasons
  has_many :sports, through: :seasons
  accepts_nested_attributes_for :sports, :seasons
end

class Sport < ActiveRecord::Base
    has_many :seasons
    has_many :spots, through: :seasons
end

class Season < ActiveRecord::Base
  belongs_to :spot
  belongs_to :sport

end

我想创建一个表格，以便您可以编辑 Spot create/edit 特定运动的季节。

我是这样工作的：

= form_for([@country, @spot], :html => { :multipart => true }) do |f|

#some Rails code here

  = f.fields_for :seasons do |builder|
    = builder.select :sport_id, options_from_collection_for_select(Sport.all, :id, :name, :sport_id)
    = builder.text_field :months
    = builder.hidden_field :spot_id

但是它不会将任何运动标记为 "selected"。我不知道在选项中用“:sport_id”代替什么。

我在没有 Rails 表单助手的情况下也能正常工作，但似乎可以通过助手来完成：

  - @spot.seasons.each do |season| 
    = select_tag "spot[seasons_attributes][][sport_id]", options_from_collection_for_select(Sport.all, :id, :name, season.sport.id)
    = hidden_field_tag 'spot[seasons_attributes][][id]', season.id
    = text_field_tag 'spot[seasons_attributes][][months]', season.months

提前致谢，瓦迪姆

Answer 1

在表单生成器上使用 collection_select 助手。

builder.collection_select(:sport_id, Sport.all, :id, :name)

嵌套属性的表单助手 has_many 到 rails 4

Form helpers for nested attributes has_many through in rails 4

ruby-on-rails

nested-forms

nested-attributes

ruby-on-rails-4