Rails嵌套屬性不保存

Question

我是新來的rails和正在學習完成學校的庫存系統數據庫項目。

這裏是我的項目模型：

class Item < ActiveRecord::Base 
    self.primary_key ='item_id' 

    validates :item_id, :presence => true 

    has_one :vendor_item, :dependent => :destroy 
    has_one :vendor, :through => :vendor_item 

    accepts_nested_attributes_for :vendor_item 
end 

這裏是我的項目控制器：

class ItemsController < ApplicationController 
    def new 
     @item = Item.new 
     @all_vendors = Vendor.all 
     @item_vendor = @item.build_vendor_item 

    end 

    def create 
    @item = Item.new(item_params) 


    vendor = params[:vendors][:id] 
    @item_vendor = @item.build_vendor_item(:vendor_id => vendor) 
    @item_vendor.save 

    #raise params.inspect 
    if @item.save 
     redirect_to @item 
    else 
     render 'new' 
    end 
    end 

    def show 
     @item = Item.find(params[:id]) 
     @item_vendor = @item.vendor_item 

    end 

    def index 
     @items = Item.all 

    end 

    def priceUnder500 
     @priceUnder500 = Item.where("price < ?", 500) 
     respond_to do |format| 
     format.html 
     format.js 
     end 
    end 

    def priceOver500 
     @priceOver500 = Item.where("price > ?", 500) 
     respond_to do |format| 
     format.html 
     format.js 
     end 
    end 

    def edit 
     @item = Item.find(params[:id]) 
     @all_vendors = Vendor.all  
     @vendor_item = @item.vendor_item 
    end 

    def update 
     @item = Item.find(params[:id]) 
     vendor = params[:vendors][:id]  

     if @item.vendor_item.blank? 
     @item.build_vendor_item(:vendor_id => vendor) 
    end 


     if @item.update(params[:item].permit(:item_id, :name, :category, :description, :reorder_level, :quantity, :price, :vendor_item_attributes => [:vendor_item_id])) 
     redirect_to items_path 
     else 
     render 'edit' 
     end 
    end 

    def destroy 
     @item = Item.find(params[:id]) 
     @item.destroy 


     redirect_to items_path 
    end 



    private 
    def item_params 
     params.require(:item).permit(:item_id, :name, :category, :description, :reorder_level, :quantity, :price, :vendor_item_attributes => [:vendor_item_id]) 
    end 
    end 

而且我_form部分物品：

<%= form_for @item do |f| %> 
    <% if @item.errors.any? %> 
    <div id="error_explanation"> 
    <h2><%= pluralize(@item.errors.count, "error") %> prohibited 
     this post from being saved:</h2> 
    <ul> 
    <% @item.errors.full_messages.each do |msg| %> 
     <li><%= msg %></li> 
    <% end %> 
    </ul> 
    </div> 
    <% end %> 

    <p> 
    <%= f.label :item_id, 'Item Id' %><br> 
    <%= f.text_field :item_id %> 
    </p> 

    <%= fields_for @item_vendor do |vii| %> 
    <div class= "vendorItemId"> 

    <%= vii.label :vendor_item_id%> 
    <%= vii.text_field :vendor_item_id%><br> 

    </div> 
    <% end %> 

    <p> 
    <%= f.label :name %><br> 
    <%= f.text_field :name %> 
    </p> 

    <p> 
    <%= f.label :category %><br> 
    <%= f.text_field :category %> 
    </p> 

    <p> 
    <%= f.label :description %><br> 
    <%= f.text_area :description %> 
    </p> 

    <p> 
    <%= f.label :reorder_level %><br> 
    <%= f.text_field :reorder_level %> 
    </p> 

    <p> 
    <%= f.label :quantity %><br> 
    <%= f.text_field :quantity %> 
    </p> 

    <p> 
    <%= f.label :price %><br> 
    <%= f.text_field :price %> 
    </p> 

    <h3>Vendors:</h3> 
    <%= fields_for(@item_vendor) do |ab| %> 
    <div class= "field"> 

    <%= ab.label "All Vendors:" %><br> 
    <%= collection_select(:vendors, :id, @all_vendors, :id, :name, {},{:multiple => false})%> 
    </div> 
    <% end %> 


    <p> 
    <%= f.submit %> 
    </p> 

<% end %> 

vendor_item包含引用ITEM_ID ，vendor_id，還有vendor_item_id的另一個屬性。當程序保存時，item_id和vendor_id保存但vendor_item_id不保存。我嘗試了所有在線來源，但似乎無法獲得保存的一個屬性。我正在使用rails 4.提前感謝您提供的任何幫助。

Answer 1

def create 
    @item = Item.new(item_params) 

    @vendor = params["item"]["vendors"] 


    if @item.save 
     @item.create_vendor_item(@vendor.id => vendor).save 
     redirect_to @item 
    else 
     render 'new' 
    end 
    end 

Answer 2

您尚未將結果保存在create操作的實例變量中。

嘗試在您的創建操作中給予這樣的效果。

def create 
    @item = Item.new(item_params) 

    vendor = params[:vendors][:id] 
    @item_vendor = @item.build_vendor_item(:vendor_id => vendor) 

    if @item.save 
     redirect_to @item 
    else 
     render 'new' 
    end 
    end