data (){  return {    fullHeight: document.documentElement.clientHeight  }}

mounted() {   const that = this   window.onresize = () => {    return (() => {     window.fullHeight = document.documentElement.clientHeight     that.fullHeight = window.fullHeight    })()   }  }

 watch: {   fullHeight (val) {    if(!this.timer) {     this.fullHeight = val     this.timer = true     let that = this     setTimeout(function (){      that.timer = false     },400)    }   }  }