index.html

<!DOCTYPE html>
<html lang="zh-cn">
<head>
    <meta charset="UTF-8">
    <title>RefLine Demo</title>

    <style>
        .box {
            width: 50px;
            height: 50px;
            position: absolute;
        }
    </style>
</head>
<body>

<div class="box" style="top:0; left:0;background: seagreen;"></div>
<div class="box" style="top:70px; left:0;background: chartreuse;"></div>
<div class="box" style="top:140px; left:0;background: saddlebrown;"></div>
<div class="box" style="width:80px;top:210px; left:0;background: salmon;"></div>
<div class="box" style="width:100px;top:280px; left:0;background: sandybrown;"></div>
<div class="box" style="width:120px;top:350px; height: 20px; left:0;background: skyblue;"></div>


<script src="./vendors/z-Dragify.js"></script>
<script src="./dist/ref-line.min.js"></script>
<script>
    let boxes   = Array.from(document.querySelectorAll('.box'))
    let refLine = new RefLine()

    boxes.forEach((item) => {
        let drag = new Dragify(item)

        drag
            .on('move', () => {
                refLine.check(drag.$elem, '.box')
            })
            .on('end', () => {
                refLine.uncheck()
            })
    })

</script>
</body>
</html>