echarts移动markline（拖拽单条markline）

效果

请添加图片描述

问题由来：

图表中需要一个移动的标线，辅助观察图表；

想法：

意思是在原来点或者原来标线上新增一个图层，拖动图层动态绘制新的点或者新的标线;

参考文档：

1.可拖拽的点
https://echarts.apache.org/examples/zh/editor.html?c=line-draggable
2.区域绘制
https://echarts.apache.org/zh/option.html#graphic.elements-rect.type
3.别人1博客
https://blog.csdn.net/Pumpkinman/article/details/105008030

自己练习的demo

<!--
  此示例下载自 https://echarts.apache.org/examples/zh/editor.html?c=line-simple&code=PYBwLglsB2AEC8sDeAoWsAeBBDEDOAXMmurGAJ4gCmRA5AMYCGYVA5sAE7m0A0J6AE2aMiAbVoBZGL1i0AKgFcqM2gHUqAlXIAWClQDEOEFQGVmphdFoBdEgF8-6cjnxFUpMpRqyAbowA2SrT2jrB4VEZUhLCi_MQegsJiAIwArAAMPLAATADMmTnZACxZ2ckAHFnJualVRQDspQBs6dahHhTUdP4Q0MrtpAC2jBwA1gAyvd7uCeh45IMARsD-YrTQMP2yG302Ax7-jItUq8hh2sAA7kQAZgHhsA5xB1MmFP7Tzwn0K5x0AMT6fTpEHpXhfDyXCACMDaIglCGkTreWh4FbQ4KzdBPLGwIRgEQxJCwZy4aIVdKPWyzOxxWnoWx2ADcQA
  ⚠ 请注意，该图表不是 Apache ECharts 官方示例，而是由用户代码生成的。请注意鉴别其内容。
-->
<!DOCTYPE html>
<html lang="zh-CN" style="height: 100%">

<head>
    <meta charset="utf-8">
</head>

<body style="height: 100%; margin: 0">
    <div id="container" style="height: 100%"></div>
    <script type="text/javascript" src="https://fastly.jsdelivr.net/npm/echarts@5.4.3/dist/echarts.min.js"></script>
    <script type="text/javascript">
    var dom = document.getElementById('container');
    var myChart = echarts.init(dom, null, {
        renderer: 'canvas',
        useDirtyRect: false
    });
    var app = {};
    var option;

    //初始值
    var markLineYAxis = 180;
    option = {
        xAxis: {
            type: 'category',
            data: ['Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat', 'Sun']
        },
        yAxis: {
            type: 'value',
            id: '2', //指定id
        },
        series: [{
            id: "aaa",
            animation: false,
            data: [150, 230, 224, 218, 135, 147, 260],
            type: 'line',


            // 这里是标线的展示形式
            markLine: {
                animation: false,
                symbol: ['none', 'none'],
                label: {
                    show: true,
                    position: 'start',
                    color: '#FF0000',
                    formatter: (params) => { return "标线" + params.value }
                },
                lineStyle: {
                    color: '#FF0000',
                    width: 4,
                    type: 'solid'
                },
                data: [{ yAxis: markLineYAxis}]
            }

        }]
    };

    myChart.setOption(option);

    // 增加适配宽度
    var showWidth =2000;
    showWidth = window.innerWidth || document.documentElement.clientWidth;
    showWidth = showWidth
    console.log(showWidth)




    //以下实现拖住功能
    var option2;
    option2 = {
        // 绘制阈值的graphic line
        graphic: {
            type: 'rect',
            z: 100,
            shape: {
                width: showWidth,  
                height: 0
            },

            //构造坐标扔进去
            position: [0, myChart.convertToPixel({ yAxisId: '2' }, markLineYAxis)],  
            draggable: true,
            style: {
                fill: 'rgba(0,0,0,0)',  // fill: 'rgba(0,0,0,0.03)',  方便观察
                stroke: 'rgba(0,0,0,0)', // stroke: 'rgba(0,0,0,0.03)',  方便观察
                lineWidth: 10
            },
            cursor: 'move',
            ondrag: onPointDragging
        },
    }
    myChart.setOption(option2);

    function onPointDragging() {
        //阈值变动
        console.log(this.position)
        //取动态值，设置进去
        yAxis = myChart.convertFromPixel({ yAxisId: '2' }, this.position[1]);
        myChart.setOption({
            series: [{
                id: 'aaa',
                markLine: {
                    data: [
                        { yAxis: yAxis },
                    ],
                }
            }]
        });
    }
    </script>
</body>

</html>