創建一個表格，刪除屬於產品的上傳

Question

我做了多次上傳與回形針基於這個應用程序 https://github.com/websymphony/Rails3-Paperclip-Uploadify它的工作正常，但現在我需要建立一個表單，用戶可以刪除一些這種上傳。

我有這樣的形式用於刪除上傳一個產品

<%= form_for @product, :html => { :method => :put }, :html => { :multipart => true } do |f| %> 
    <h3 id="photos_count"><%= pluralize(@product.uploads.size, "Photo")%></h3> 
    <%= f.fields_for :uploads do |photo_fields| %> 
    <% if !photo_fields.object.nil? and !photo_fields.object.new_record? %> 
     <%= image_tag(photo_fields.object.photo.url(:thumb)) %> 
     <p><%= photo_fields.check_box :_destroy, :class=>'checkbox' %> Delete item</p> 
    <% end %> 
    <% end %> 
<% end %> 

這種形式以某種方式顯示正確的上傳數，我可以在與PRODUCT_ID = product.id所有上傳中找到的終端窗口看到數據庫中，但我沒有在頁面上顯示圖像，你可以在圖像上看到：

終端

Started GET "/admin/products/40" for 127.0.0.1 at Tue Apr 10 10:20:06 +0300 2012 
    Processing by Admin::ProductsController#show as HTML 
    Parameters: {"id"=>"40"} 
Creating scope :page. Overwriting existing method AdminUser.page. 
    AdminUser Load (2.4ms) SELECT `admin_users`.* FROM `admin_users` WHERE `admin_users`.`id` = 5 LIMIT 1 
Creating scope :page. Overwriting existing method Product.page. 
    Product Load (0.5ms) SELECT `products`.* FROM `products` WHERE `products`.`id` = 40 LIMIT 1 
Creating scope :page. Overwriting existing method Upload.page. 
    Upload Load (0.4ms) SELECT `uploads`.* FROM `uploads` WHERE `uploads`.`product_id` = 40 AND (file_avatar = 1) LIMIT 1 
Creating scope :page. Overwriting existing method Category.page. 
    Category Load (0.4ms) SELECT `categories`.* FROM `categories` WHERE `categories`.`id` = 2 LIMIT 1 
    (0.6ms) SELECT COUNT(*) FROM `uploads` WHERE `uploads`.`product_id` = 40 
Rendered admin/products/_delete_photos.html.erb (154.3ms) 
    CACHE (0.0ms) SELECT COUNT(*) FROM `uploads` WHERE `uploads`.`product_id` = 40 

附加信息：

upload.rb

class Upload < ActiveRecord::Base 
    attr_accessible :product_id, :photo 
    belongs_to :product 
    has_attached_file :photo, :styles => { :medium => "300x300>", :thumb => "100x100>" } 

    attr_accessible :created_at, :photo_file_size, :photo_file_name, :updated_at, :photo_content_type, 
        :file_avatar, :photo_updated_at, :uploads_attributes, :photo_attributes 
end 

product.rb

class Product < ActiveRecord::Base 
    has_many :uploads, :dependent => :destroy 
    accepts_nested_attributes_for :uploads, :allow_destroy => true 
end 

uploads_controller.rb

# GET /uploads/1/edit 
    def edit 
    @upload = Upload.find(params[:id]) 
    end 

    # POST /uploads 
    # POST /uploads.xml 

    # PUT /uploads/1 
    # PUT /uploads/1.xml 
    def update 
    @upload = Upload.find(params[:id]) 

    respond_to do |format| 
     if @upload.update_attributes(params[:upload]) 
     format.html { redirect_to(@upload, :notice => 'Upload was successfully updated.') } 
     format.xml { head :ok } 
     else 
     format.html { render :action => "edit" } 
     format.xml { render :xml => @upload.errors, :status => :unprocessable_entity } 
     end 
    end 
    end 

    # DELETE /uploads/1 
    # DELETE /uploads/1.xml 
    def destroy 
    @upload = Upload.find(params[:id]) 
    @upload.destroy 

    respond_to do |format| 
     format.html { redirect_to(products_url) } 
     format.xml { head :ok } 
    end 
    end 

所以這裏的問題是：爲什麼圖像不顯示旁邊的複選框。謝謝。

更新

Processing by ProductsController#update as HTML 
    Parameters: {"commit"=>"Delete sellected photos", "authenticity_token"=>"af5+YybkZ1KMu/DmZmlui9frqQX5ka8v/vvv0hi9PVo=", "id"=>"42", "product"=>{"uploads_attributes"=>{"7"=>{"id"=>"322", "_destroy"=>"1"}, "6"=>{"id"=>"321", "_destroy"=>"0"}, "5"=>{"id"=>"320", "_destroy"=>"0"}, "4"=>{"id"=>"319", "_destroy"=>"0"}, "3"=>{"id"=>"318", "_destroy"=>"0"}, "2"=>{"id"=>"317", "_destroy"=>"0"}, "1"=>{"id"=>"316", "_destroy"=>"0"}, "0"=>{"id"=>"315", "_destroy"=>"0"}}}, "utf8"=>"✓"} 

後，傑西的答覆我現在已經在我的網頁圖像，與複選框，但我查了一些人後，按下提交按鈕的照片不會被刪除

products_controller

DEF更新 @product = Product.find（PARAMS [：ID]）

respond_to do |format| 
    if @product.update_attributes(params[:product]) 
    format.html { redirect_to(@product, :notice => 'Product was successfully updated.') } 
    format.xml { head :ok } 
    else 
    format.html { render :action => "edit" } 
    format.xml { render :xml => @product.errors, :status => :unprocessable_entity } 
    end 
end 

末

Answer 1

你試圖使用nested_attributes，但尚未啓用，該產品的型號

class Product < ActiveRecord::Base 
    has_many :uploads, dependent: :destroy, autosave: true 
    accepts_nested_attributes_for :uploads, allow_destroy: true, reject_if: :all_blank 
end 

更多：http://apidock.com/rails/ActiveRecord/NestedAttributes/ClassMethods/accepts_nested_attributes_for