vue mounted中监听div的变化

vue mounted中监听div的变化

<div  >{{$store.state.msg}}</div>

methods: {
  fun(){
    this.$store.dispatch('fun',this.checkedNames);
  },

mounted(){
  document.getElementById('list').addEventListener("DOMSubtreeModified", function(){
    var he=document.getElementById('list').offsetHeight;
    document.getElementById('list2').style.height=he+'px';
    console.log(he);
  }, false)
}