需求

有一个按钮实现对Echarts的指定缩放与拉长，形成自适应效果

拉长后效果图

该块元素缩短后效果图

分析

因为我习惯使用 ref 来获取组件的 DOM 元素，然后进行挂载

<div ref="echartsRef" id="myDiv" :style="{ width, height }"></div>

echartInstance = echarts.init(echartsRef.value, 'macarons');

• 小插入————踩坑【别试】
  想的是通过document.querySelector 修改宽高，但是并未监听到 ref 的宽高被修改【未成功】
  网上有说是要销毁 DOM 重新进行绘制，【未成功】

watch(flagFold, (newVal) => {
    echartResizes(echartInstance)
    const myDiv = document.querySelector('#myDiv ')
    myDiv.style.width = newVal ? '1400px' : '600px'
    if (echartInstance) {
        echartInstance.resize();
    }
})

因此采用如下解决办法

因此在监听变化的时候，要修改 ref 获取到的元素的宽度和高度

<template>
  <div>
    <!-- 使用 ref 来获取组件的 DOM 元素 -->
    <div ref="echartsContainer" :style="{ width: containerWidth + 'px', height: containerHeight + 'px' }"></div>
  </div>
</template>

<script>
import { ref, onMounted, watch } from 'vue';
import echarts from 'echarts';

export default {
  setup() {
    // 使用 ref 来创建响应式对象
    const echartsContainer = ref(null);
    const containerWidth = ref(0);
    const containerHeight = ref(0);
    let echartsInstance;

    onMounted(() => {
      // 初始化 ECharts 实例
      echartsInstance = echarts.init(echartsContainer.value);

      // 在组件挂载后调整组件宽度和高度
      adjustSize();
    });

    // 监听组件宽度和高度变化
    watch([() => echartsContainer.value.offsetWidth, () => echartsContainer.value.offsetHeight], ([newWidth, newHeight], [oldWidth, oldHeight]) => {
      // 当组件宽度或高度发生变化时调用 adjustSize 方法
      adjustSize();
    });

    const adjustSize = () => {
      // 获取组件宽度和高度
      containerWidth.value = echartsContainer.value.offsetWidth;
      containerHeight.value = echartsContainer.value.offsetHeight;

      // 修改组件宽度和高度
      echartsInstance.resize({
        width: containerWidth.value,
        height: containerHeight.value
      });
    };

    return {
      echartsContainer,
      containerWidth,
      containerHeight
    };
  }
}
</script>

• 源码展示

<template>
    <div ref="echartsRef" id="myDiv" :style="{ width, height }"></div>
</template>

<script lang="ts" setup>
import {
    ref,
    reactive,
    watch,
    toRefs,
    onMounted,
    onBeforeUnmount,
    computed,
    watchEffect
} from 'vue';
import * as echarts from 'echarts';
import { echartResize, echartResizes } from "@/utils/echsrts";
import { useToolStore } from '@/store';


const ToolStore = useToolStore()

const flagFold = computed(() => {
    return ToolStore.isFold
})
watch(flagFold, (newVal) => {
    echartResizes(echartInstance)
    // const myDiv = document.querySelector('#myDiv ')
    // myDiv.style.width = newVal ? '1400px' : '600px'
    echartInstance.resize({
        width: newVal ? 1400 : 600,
    });
    if (echartInstance) {
        echartInstance.resize();
    }
})

/**
 * @description : 安全监测模块
 * @author : 'Hukang'
 * @param : '' 
 * @date : 2024-03-05 14:59:56
*/
const props = defineProps({
    //子组件接收父组件传递过来的值
    chartData: Object,
    width: {
        type: String,
        default: '600px',
        required: false // 是否必传
    },
    height: {
        type: String,
        default: '580px',
        required: false // 是否必传
    }
})
//使用父组件传递过来的值
const { chartData } = toRefs(props)



const option = ref({
    title: {
        text: ''
    },
    tooltip: {
        trigger: 'axis',
        axisPointer: {
            type: 'cross',
            label: {
                backgroundColor: '#6a7985'
            }
        }
    },
    legend: {
        data: [],
        right: "5%",
        top: "0",
        textStyle: {
            fontSize: 12, //字体大小
            color: "#000" //字体颜色
        }
    },
    toolbox: {
        feature: {
            saveAsImage: {
                show: true,
                title: '点击保存'
            }
        },
        right: '10%', // 从右边缘的距离
        top: '10%'
    },
    grid: {
        left: '3%',
        right: '8%',
        bottom: '8%',
        top: '15%',
        containLabel: true
    },
    xAxis: {
        type: "category",
        boundaryGap: false,
        data: [],
        axisLine: {
            lineStyle: {
                color: "#000"
            }
        },
        axisTick: {
            show: true//刻度线
        },
        nameTextStyle: {
            color: "#000",
            fontSize: 12
        },
        axisLabel: {
            color: "#000",
            fontSize: 12,
            formatter: (value, index) => {
                return value.replace(/(\d{4})-(\d{1,2})-(\d{1,2}).*/, "$1-$2-$3").slice(5);
            }
        }
    },
    yAxis: [
        {
            name: '',
            type: "value",
            axisTick: {
                show: true
            },
            nameTextStyle: {
                color: "#000",
                fontSize: 12
            },
            axisLine: {
                show: true,
                lineStyle: {
                    color: "#000"
                }
            },
            splitLine: {
                lineStyle: {
                    type: "dashed", //虚线
                    color: "rgba(0,0,0,0.8)"
                },
                show: true //隐藏
            },
            min(v) {
                return v.min
            }
        }
    ],
    dataZoom: [
        {
            show: true,
            type: 'slider',
            handleSize: 32, // 两边的按钮大小
        },
        {
            type: 'inside'
        }
    ],
    series: [],
})


const echartsRef = ref<string>();
let echartInstance;
watch(chartData, (newVal) => {
    if (newVal) {
        option.value = newVal
        echartInstance.setOption(option.value);
        window.addEventListener('resize', () => {
            if (echartInstance) {
                echartInstance.resize();
            }
        })
    }
}, { deep: true })




onMounted(() => {
    echartInstance = echarts.init(echartsRef.value, 'macarons');

})
onBeforeUnmount(() => {
    if (echartInstance && echartInstance.dispose) {
        echartInstance = null;
    }
})
</script>



<style scoped lang="less"></style>