rails 3,paperclip(&formtastic) - 删除图像附件

Question

我似乎无法找到所有组件中完整的示例.我很难删除图片附件

1. 类

     class Product
       has_many :product_images, :dependent => :destroy
       accepts_nested_attributes_for :product_images
     end
   
     class ProductImage
       belongs_to :product
       has_attached_file :image #(etc)
     end
   

2. 视图

     <%= semantic_form_for [:admin, @product], :html => {:multipart => true} do |f| %>
       <%= f.inputs "Images" do %>
         <%= f.semantic_fields_for :product_images do |product_image| %>
           <% unless product_image.object.new_record? %>
             <%= product_image.input :_destroy, :as => :boolean, 
                :label => image_tag(product_image.object.image.url(:thumb)) %>
           <% else %>
             <%= product_image.input :image, :as => :file, :name => "Add Image" %>
           <% end %>
         <% end %>
       <% end %>
     <% end %>
   

3. 调节器

     class Admin::ProductsController < AdminsController
      def edit
        @product = Product.find_by_permalink(params[:id])
        3.times {@product.product_images.build} # added this to create add slots
      end
   
      def update
         @product = Product.find_by_permalink(params[:id])
   
         if @product.update_attributes(params[:product])
           flash[:notice] = "Successfully updated product."
           redirect_to [:admin, @product]
         else
           flash[:error] = @product.errors.full_messages
           render :action => 'edit'
         end
       end
     end
   

看起来不错,但是,当我选中复选框时,几乎没有任何反应.在请求中我看到:

      "product"=>{"manufacturer_id"=>"2", "size"=>"", "cost"=>"5995.0", 
         "product_images_attributes"=>{"0"=>{"id"=>"2", "_destroy"=>"1"}}

但没有任何更新,产品图像也不会保存.

我错过了关于'accepts_nested_attributes_for'如何工作的基本信息吗？

Answer 1

来自ActiveRecord :: NestedAttributes :: ClassMethods的API文档

:allow_destroy

如果为true,则使用_destroy键和计算结果为true的值(例如,1,'1,true或'true')销毁属性哈希中的所有成员.默认情况下,此选项处于关闭状

所以:

accepts_nested_attributes_for :product_images, allow_destroy: true