费不多说，直接代码：

`// pages/test1/test1.js	var num = 10,	interval = null,	min = 0;	Page({	  /**	   * 页面的初始数据	   */	  data: {		time:10	  },	  onClickTimeStart(){		startTime();	  }	  ,	  startTime: function(){		console.log("开始点击");		var that = this;		interval = setInterval(function(){		  console.log(num + "-- 循环次数");		  num--;		  if(num <= min){			clearInterval(interval);			wx.showToast({			  title: '结束了',			  icon: '',			  image: '',			  duration: 1,			  mask: true,			  success: function(res) {},			  fail: function(res) {},			  complete: function(res) {},			})		  }		that.setData({time:num})		},1000);	  }	})`