未显示嵌套表单对象字段

Question

我正在使用Padrino，并尝试在具有许多图像的对象的表单中显示图像上传字段。
模型 工程。rb

class Project < ActiveRecord::Base
  has_many :images, class_name: 'ProjectImage', foreign_key: 'project_id'
  accepts_nested_attributes_for :images, allow_destroy: true
end

模型 project_image。rb

class ProjectImage < ActiveRecord::Base
  belongs_to :project
  mount_uploader :file, ProjectUploader
end

管制员 项目。rb

get :new do
  @title = pat(:new_title, :model => 'project')
  @project = Project.new
  @project.images.build
  render 'projects/new'
end

部分 项目/_form.哈姆尔

= form_for :project, url(:projects, :create), multipart: true, :class => 'form-horizontal' do |f|
  - f.fields_for :images do |image_f|
    =image_f.label :file, :class => 'control-label'
    .controls
      =image_f.file_field :file, :class => 'form-control input-xlarge input-with-feedback', :multiple => true

但嵌套 image_f 字段不显示。有什么想法吗？

Answer 1

改变:

= form_for :project, url(:projects, :create), multipart: true, :class => 'form-horizontal' do |f|

到

= form_for @project, url(:projects, :create), multipart: true, :class => 'form-horizontal' do |f|

很可能你也需要改变 - f.fields_for 到 = f.fields_for