vue实现商城购物车功能(2)

export default {
 data () {
  return {
  good_list: [
   {
   title: 'Apple iPhone 6s 16GB 玫瑰金色 移动联通电信4G手机',
   img: "http://sc.tywebs.cn/public/upload/goods/2017/04-27/a767693b9a84747f25335f0e33d3d380.jpg",
   num: 2,
   price: 6070.00,
   spec_item:[
    '内存:16G',
    '网络:4G',
    '颜色:玫瑰金'
   ],
   is_selected: false
   },{
   title: 'Apple iPhone 6s 32GB 玫瑰金色 移动联通电信4G手机',
   img: 'http://sc.tywebs.cn/public/upload/goods/2017/04-27/a767693b9a84747f25335f0e33d3d380.jpg',
   num: 2,
   price: 4570.00,
   spec_item:[
    '内存:32G',
    '网络:4G',
    '颜色:玫瑰金'
   ],
   is_selected: true
   },{
   title: 'Apple iPhone 6s 8GB 玫瑰金色 移动联通电信4G手机',
   img: 'http://sc.tywebs.cn/public/upload/goods/2017/04-27/a767693b9a84747f25335f0e33d3d380.jpg',
   num: 2,
   price: 4870.00,
   spec_item:[
    '内存:8G',
    '网络:4G',
    '颜色:玫瑰金'
   ],
   is_selected: false
   },{
   title: 'Apple iPhone 6s 128GB 玫瑰金色 移动联通电信4G手机',
   img: 'http://sc.tywebs.cn/public/upload/goods/2017/04-27/a767693b9a84747f25335f0e33d3d380.jpg',
   num: 2,
   price: 10568.00,
   spec_item:[
    '内存:128G',
    '网络:4G',
    '颜色:玫瑰金'
   ],
   is_selected: true
   },
  ],
  totalPrice: 0,
  totalNum: 0,
  selected_all: false
  }
 },
 mounted: function () {
  this.getTotal();
 },
 watch: {
  'good_list': {
  handler: function (val, oldVal) {
   // console.log(val)
   return val;
  },
  deep: true
  }
 },
 methods: {
  getTotal () {
  this.totalPrice = 0
  this.totalNum = 0
  for (var i = 0; i < this.good_list.length; i++) {
   var _d = this.good_list[i]
   if(_d.is_selected){
   this.totalPrice += _d['price'] * _d['num']
   this.totalNum +=_d['num']
   }
  }
  },
  select_one (index) {
  if(this.good_list[index].is_selected == true){
   this.good_list[index].is_selected = false
  }else{
   this.good_list[index].is_selected = true
  }
  this.getTotal()
  },
  slect_all () {
  if(this.selected_all){
   for (var i = 0; i < this.good_list.length; i++) {
   this.good_list[i].is_selected = false;
   }
   this.selected_all = false   
  }else{
   for (var i = 0; i < this.good_list.length; i++) {
   this.good_list[i].is_selected = true;
   }
   this.selected_all = true   
  }
  this.getTotal()
  },
  reduce (index) {
  if(this.good_list[index].num <= 1) return;
  this.good_list[index].num --
  this.getTotal()
  },
  add (index) {
  this.good_list[index].num ++
  this.getTotal()
  }
 }
 }