监测点代码优化

src/components/echarts/MyEchart.vue

@@ -16,7 +16,8 @@ const props = defineProps(['options'])
 let chart: echarts.ECharts | any = null
 const resizeHandler = () => {
     // 不在视野中的时候不进行resize
-    if(chartRef.value!.offsetHeight == 0) return
+    if (!chartRef.value) return
+    if (chartRef.value.offsetHeight == 0) return
     chart.getZr().painter.getViewportRoot().style.display = 'none'
     requestAnimationFrame(() => {
         chart.resize()