核心：在dom加载完成后调用echarts实例 的resize()方法
这里是一个例子
这里封装一个echarts

<template>
    <div class="container" ref="container"></div>
</template>
<script lang="ts" setup>
import { ref, toRefs, watch, onMounted, nextTick, markRaw, onBeforeMount, inject } from 'vue'
const container = ref<HTMLElement>()
const myChart = ref<any>()
const $echart: any = inject("$echart")
const props = defineProps({
    options: {
        require: true,
        type: Object,
        default: {}
    }

})
const { options } = toRefs(props)
onBeforeMount(() => {
    window.removeEventListener('resize', resizeHandler);
})
onMounted(() => {
    myChart.value = markRaw($echart.init(container.value)) //获取echarts实例使用markRaw解除响应式
    myChart.value.setOption(options.value)//设置echarts配置项
    window.addEventListener('resize', resizeHandler) //监听浏览器窗口大小
})
//核心在这，加载完成后调用该方法，使图表撑满父容器
const resizeHandler = () => {
    nextTick(() => {
        myChart.value.resize() //设置图表自适应大小
    })
}
watch(options, (newOptions) => {
    nextTick(() => {
        myChart.value.setOption(newOptions) //监听父组件传入的options,发生变化时从新设置配置项
    })
},
    { deep: true })
//记得将方法暴漏出去
defineExpose({
    resizeHandler
})
</script>
<style scoped>
.container {
    width: 100%;
    height: 50vh;
}
</style>

在子组件中使用echarts

//在子组件中引入使用echarts
import { ref, nextTick } from 'vue';
<el-dialog v-model="dialogVisible" width="1200" center>
	<kdEcharts :options="lineOption" v-if="dialogVisible" ref="kdEchartsR"> </kdEcharts>
</el-dialog>            
 <script setup>
 const dialogVisible = ref(false)
		const kdEchartsR = ref()
		const open = () => {
	    dialogVisible.value = true
	    nextTick(() => {
	        lineOption.value = {
	            tooltip: {
	                trigger: "axis",
	                axisPointer: {
	                    type: "line"
	                }
	            },
	            xAxis: {
	                type: 'category', //x轴设置为类目轴
	                data: ['Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat', 'Sun']
	            },
	            yAxis: {
	                type: 'value', //y轴设置为数值轴
	                splitLine: {
	                    lineStyle: {
	                        type: 'dashed'
	                    }
	                }
	            },
	            series: [
	                {
	                    data: [1200, 25565, 224, 218, 135, 147, 260],
	                    type: 'line',//设置图表的类型为折线图,
	                    smooth: true,
	                    symbol: "none",
	                    itemStyle: {
	                        color: "#ff2e4d",
	                    },
	                    emphasis: { disabled: true },
	                    lineStyle: {
	                        color: '#ff2e4d'
	                    },
	                    areaStyle: {
	                        color: {
	                            type: 'linear',
	                            x: 0,
	                            y: 0,
	                            x2: 0,
	                            y2: 1,
	                            colorStops: [
	                                {
	                                    offset: 0,
	                                    color: "#ff2e4d" // 0% 处的颜色
	                                },
	                                {
	                                    offset: 1,
	                                    color: '#fff' // 100% 处的颜色
	                                }
	                            ],
	                            global: false // 缺省为 false
	                        }
	                    }
	                }
	            ]
	        }
	        kdEchartsR.value.resizeHandler()
	    })
	}
	defineExpose({
	    dialogVisible, open
	})
</script>

父组件中调用子组件

<templete>
	<detail-t ref="detailR"></detail-t>
</templete>
<script setup>
import { reactive, ref } from 'vue';
const detailR = ref()
在需要显示弹框的的方法中调用即可
detailR.value.open()
</script>