<view class='out' style='margin-top:10px'>
 <view class='in' style='width:{{progressWidth}}%'></view>
</view>
<view class='caozuo'>
 <text>{{progressTime}}秒</text>
 <text bindtap='playbtn' data-change='1'>{{playPausetips}}</text>
</view>

.out {margin-left:auto;margin-right:auto;width:250px;height:20px;border:1px solid red;border-radius:20px;overflow:hidden;}
.in {height:100%;background-color:red;}
.caozuo{font-size:14px;color:#333;margin-left:auto;margin-right:auto;width:250px;margin-top:10px;display: flex;justify-content:space-between}

Page({
 data: {
  progressWidth:0,progressTime:60,mark:true,playPausetips:"开始"
 },playbtn() {
  let that = this;
  let mark = that.data.mark;
  if (mark){
   that.timer = setInterval(that.run,1000); //that.timer关键点
   wx.showToast({
    title: '开始',})
   that.setData({
    mark:false,playPausetips:"暂停"
   })
  }else{
   clearInterval(that.timer);
   wx.showToast({
    title: '暂停',})
   that.setData({
    mark: true,playPausetips: "开始"
   })
  }
 },run(){
  let that = this;
  let totalProgressTime = 60 //秒
  let progressWidth = that.data.progressWidth; //显示进度
  let progressTime = that.data.progressTime; //时间
 
  if (progressWidth === 100) {
   wx.showToast({
    title: '结束回调处理',})
   clearInterval(that.timer);
   that.setData({
    progressTime: totalProgressTime,//进度条需要总时间s
    progressWidth: 100,//进度100%
    progressTime: 60
   })
   return;
  }
  progressTime--;
  progressWidth = (totalProgressTime - progressTime) * (100 / 60)
  that.setData({
   progressWidth: progressWidth,progressTime: progressTime
  })
 }
 
})