微信小程序实现倒计时调用相机自动拍照功能

//index.js

const app = getApp()
Page({
 data: {
 userInfo: {},
 counting: false//倒计时
 },
 onLoad: function () {
 this.daojishi();//一进来就拍照倒计时
 this.ctx = wx.createCameraContext()//创建摄像头对象
 },
 //倒计时
 daojishi: function () {
 var that = this;
 if (!that.data.counting) {
  //开始倒计时5秒
  countDown(that, 5);
 }
 }
})
//倒计时函数 在page外

function countDown(that, count) {
 if (count == 0) {
 //等于0时拍照 
 that.ctx.takePhoto({
  quality: 'high',
  success: (res) => {
  that.setData({
   src: res.tempImagePath
  })
  wx.showToast({
   title: '拍照完成',
  })
  }
 })
 that.setData({
  counting: false
 })
 return;
 }
 wx.showLoading({//加载时显示倒计时
 title: '拍照倒计时'+count+'秒',
 })

 setTimeout(function () {
 wx.hideLoading()
 }, 1000)
 that.setData({
 counting: true,
 })
 setTimeout(function () {
 count--;
 countDown(that, count);
 }, 1000);
}