wx.createIntersectionObserver(Object component, Object options)

// pages/text/play.js
const app = getApp()
Component({
  /**
   * 组件的属性列表
   */
  properties: {
    index: {
      type: Array,
      value: []
    }
  },
  ready() {

  },
  attached() {
    // 获取随机数字 给video标签id命名 可使用时间戳
    var random = Math.floor(Math.random() * 1000);
    // 全局获取 屏幕高度宽度
    var { screenHeight, screenWidth } = app.globalData.systemInfo
    this.setData({
      screenHeight,
      screenWidth,
      random
    })
    var that = this
    var screenHeight = screenHeight //获取屏幕高度

    var screenWidth = screenWidth //获取屏幕宽度

    let topBottomPadding = screenHeight / 2
    // 获取试图目标元素  
    const videoObserve = wx.createIntersectionObserver(this)
    // 设置试图可见区域
    this.observe = videoObserve.relativeToViewport({ top: -topBottomPadding + 10, bottom: -topBottomPadding })


    // // 暂存随机
    var random = that.data.random
    this.observe.observe(`#vids${that.data.random}`, (res) => {
      let { intersectionRatio } = res
      // var videoNow = wx.createVideoContext(res.id,that)
      if (intersectionRatio > 0) {
        //离开视界，因为视窗占比>0，开始播放

        // that.setData({

        //   playstart: true

        // })
        //进入视界，开始播放
        console.log(\'start\',res);
        wx.createVideoContext(res.id,that).play()
        wx.createVideoContext(\'vids\',that).play()
        // that.observe.disconnect()


      } else {
        // 离开试图 暂停播放
        console.log(\'stop\',res);
        wx.createVideoContext(\'vids\',that).pause()

        wx.createVideoContext(res.id,that).pause()
        // that.observe.disconnect()
        // that.setData({

        //   playstart: false

        // })
      }
    })

  },

  /**
   * 组件的初始数据
   */
  data: {
    list: [],
    playstart: false,
    screenHeight: "",
    screenWidth: "",
    random: \'\',
  },

  /**
   * 组件的方法列表
   */

  onShow() {
    
  },
  methods: {

  
  }
})

<view class="box" hover-class="none">
    <view class="">
        <video class="vids"  id="vids{{random}}" data-index=\'{{index}}\' src="http://wxsnsdy.tc.qq.com/105/20210/snsdyvideodownload?filekey=30280201010421301f0201690402534804102ca905ce620b1241b726bc41dcff44e00204012882540400&bizid=1023&hy=SH&fileparam=302c020101042530230204136ffd93020457e3c4ff02024ef202031e8d7f02030f42400204045a320a0201000400"></video>
    </view>
</view>