element-ui tab切换加载echarts无法正常显示问题

解决方案来源https://github.com/lizheng3401/echarts-in-element-doesn-t-work
解决方法：
设置当前key值与v-model绑定的值一致时才加载图表。
话不多说，直接贴码

<template>
  <div>
    <el-tabs type="card" v-model="activeName">
      <el-tab-pane
        v-for="item in tabMapOptions"
        :label="item.label"
        :key="item.key"
        :name="item.name"
      >
        <charts v-if="item.name === activeName"></charts>
      </el-tab-pane>
    </el-tabs>
  </div>
</template>
<script>
import charts from "./charts";
import "../assets/stylesheets/reset.css";
export default {
  name: "index",
  components: {
    charts
  },
  data() {
    return {
      activeName: "first",
      tabMapOptions: [
        {
          label: "二楼",
          name: "first",
        },
        {
          label: "配电间",
          name: "second",
        }
      ]
    };
  }
};
</script>

charts.vue

<template>
  <div :style="{height:height,width:width}"></div>
</template>

<script>
import * as echarts from "echarts";
export default {
  name: "charts",
  props: {
    width: {
      type: String,
      default: "100%"
    },
    height: {
      type: String,
      default: "500px"
    }
  },
  data: function() {
    return {
      chart: null
    };
  },
  mounted: function() {
    this.initChart();
  },
  beforeDestroy: function() {
    if (!this.chart) {
      return;
    }
    this.chart.dispose();
    this.chart = null;
  },
  methods: {
    setOptions: function() {
      this.chart.setOption({
        title: {
          text: "二楼"
        },
        tooltip: {
          trigger: "axis",
          axisPointer: {
            // 坐标轴指示器，坐标轴触发有效
            type: "" // 默认为直线，可选为：'line' | 'shadow'
          }
        },
       legend: {
          data: ["甲班", "乙班"]
        },
        grid: {
          left: "3%",
          right: "4%",
          bottom: "3%",
          containLabel: true
        },
        xAxis: [
          {
            type: "category",
            data: [
              "二楼工业水表",
              "二楼退浆机回用水表",
              "二楼整机回用水表",
              "二楼蒸汽表"
            ]
          }
        ],
        yAxis: [
          {
            type: "value"
          }
        ],
       series: [
          {
            name: "甲班",
            type: "bar",
            data: [22, 48, 53, 5.83]
          },
          {
            name: "乙班",
            type: "bar",
            data: [6, 9, 16, 20.69]
          }
        ]
      });
    },
    initChart: function() {
      this.chart = this.$echarts.init(this.$el);
      this.setOptions();
    }
  }
};
</script>

<style scoped>
</style>