vue数组更新界面无变化

this.arrList[this.arrList.length] = {};
this.arrList[this.arrList.length-1].dataList = newArr;
this.arrList[this.arrList.length-1].header = 'A幢';

由于 JavaScript 的限制，Vue 不能检测以下数组的变动：
    当你利用索引直接设置一个数组项时，例如：vm.items[indexOfItem] = newValue
    当你修改数组的长度时，例如：vm.items.length = newLength

this.arrList[this.arrList.length] = {};
this.$set(this.arrList,this.arrList.length-1,{dataList:newArr,header:'A幢'});