uniapp微信小程序实现一个页面多个倒计时

<view class="group-list" v-for="item in message" :key="item.productId">
 <view class="group-img" @click="navTo">
 <image :src="item.productPicture"></image>
 </view>
 <view class="group-info">
 <view class="product-name">{{ item.productName }}</view>
 <view class="product-price">
 <text class="discounts">￥{{ item.productCurrentPrice }}</text>
 <text class="original">￥{{ item.productMarketPrice }}</text>
 </view>
 <view class="group-partner">
 <scroll-view scroll-x>
 <view class="user-img">
 <view v-for="(single, index) in item.avatarList" :key="index">
 <image :src="single"></image>
 </view>
 <view v-for="i in item.stillMissingNumber" :key="i">
 <image src="../../static/ssll-img/more.png"></image>
 </view>
 </view>
 </scroll-view>
 <button open-type="share">邀请好友</button>
 </view>
 <view class="clock">
 <text>拼团剩余：</text>
 <!-- 绑定倒计时 -->
 <text>{{ item.end_time1 }}</text> 
 </view>
 </view>
</view>

export default {
 data() {
 return {
 timeData: '', //存放每条数据的处理好的倒计时
 timer: '', //用来清除定时器
 message: [] //接口请求返回的数据
 }
 },
 onUnload(){ //卸载页面清除定时器
 clearInterval(this.timer) 
 },
 methods: {
 getTimeList(){ 
 let that = this
 that.message.forEach((item) =>{
  var nowdate = new Date().getTime() //获取当前时间毫秒数
  var time = item.productExpiredTime.replace(new RegExp("-", "gm"), "/") //ios不能识别日期格式中的 "-" ； .productExpiredTime是接口返回的名称
  var timesp = time.split('.')[0] //此处是因为我们接口返回的时间格式是这样："2019-12-31 11:00:00.0"
  var enddate = new Date(timesp).getTime() //处理好格式之后获取结束时间的毫秒数
  var totaltime = enddate - nowdate //获取时间差
  that.totaltime(totaltime) //这是下面封装的方法，将毫秒数处理成"xx时xx分xx秒"
  item.end_time1 = that.timeData //处理好的单个时间安排到item上（重要）
 })
 this.message = that.message //全部处理好的数据重新赋值
 },
 totaltime(a){ //计算单个剩余时间
 let totaltime = a
 let that = this
  var h, m, s, d
  function test(num) {
  if (num < 10) {
   num = "0" + num 
  }
  return num
  }
 if (totaltime > 0) {
  d = Math.floor(totaltime / 1000 / 60 / 60 / 24) * 24
  h = Math.floor(totaltime / 1000 / 60 / 60 % 24)
  m = Math.floor(totaltime / 1000 / 60 % 60)
  s = Math.floor(totaltime / 1000 % 60)
  //获取时分秒
  h = d + h
  h = test(h)
  m = test(m)
  s = test(s)
  this.timeData =`${h}时 : ${m}分 : ${s}秒` // 每个时间的显示格式
 } else {
  this.timeData = `00 : 00 : 00` 
 }
 },
 //以下请求此页面需要的数据
 getUserGroupList(接口参数) {
 this.$ajax({
 url: 'xxx/xxx/xxxxxx',
 data: {接口参数},
 success: res => {
 var that = this
 let data = res.data.groups
 if (data.length === 0) {
 this.$api.msg('暂时您还没有参团信息！')
 setTimeout (function() {
 uni.navigateBack({ //返回上一页
  delta: 1
 })
 },1500)
 } else {
 this.message = [...that.message, ...res.data.groups] //合并
 //数据返回成功之后再调计时器，防止异步
 //that.getTimeList()
 var timer = setInterval(function () {
  that.getTimeList()
 }, 1000)
 this.timer = timer
 }
 }
 }
}