本来是想没有数据显示暂无数据的，结果显示成了这样

1.把V-show改成v-if

<template>
  <div
    class="chart1"
    ref="chart1"
    v-if="!nodata"
    style="width: 100%; height: 100%"
  ></div>
  <el-empty description="暂无数据" v-else />
</template>

2.使用nextTick

import {  nextTick } from "vue";

if (JSON.stringify(callNum) == "[]") {
   chartObj.nodata = true;
 } else {
   chartObj.nodata = false;
   nextTick(() => {
     DrawAnslysePic(callNum);
   });
 }