ruby-on-rails - fields_for 表单生成器对象为零

Question

有什么方法可以访问嵌套的 form_bulder.object？

## controller
@project = Project.new
@project.tasks.build

form_for(@project) do |f|
  f.object.nil? ## returns false

  fields_for :tasks do |builder|
    builder.object.nil? ## returns true
  end
end

Answer 1

您必须在项目模型中有 accepts_nested_attributes_for 才能传递对象。

class Project < ActiveRecord::Base
  has_many :tasks
  accepts_nested_attributes_for :tasks ## this is required
end