拖拽排序的实现示例demo

文章说明

文章主要为了学习拖拽排序的实现思路，并且采用此示例效果来进一步理解Flip动画的使用
参考渡一前端袁老师的讲解视频

核心代码

页面源码，拖拽排序的实现代码并不复杂，但是可以很好的帮助学习该示例的实现思路和拖拽API的使用

html 复制代码

<!DOCTYPE html>
<html lang="zh-cn">
    <head>
        <meta charset="UTF-8">
        <meta name="viewport" content="width=device-width, initial-scale=1.0">
        <title>拖拽排序</title>
        <style>
            * {
                box-sizing: border-box;
            }

            .container {
                margin: 100px auto auto;
                width: 200px;
            }

            .container div {
                height: 30px;
                line-height: 30px;
                margin: 10px 0;
                background-color: chocolate;
                border-radius: 10px;
                color: #ffffff;
                text-align: center;
            }

            .container .moving {
                border: dashed 1px black;
                background-color: #ffffff;
            }
        </style>
    </head>

    <body>
        <div class="container">
            <div draggable="true" class="item">1</div>
            <div draggable="true" class="item">2</div>
            <div draggable="true" class="item">3</div>
            <div draggable="true" class="item">4</div>
            <div draggable="true" class="item">5</div>
            <div draggable="true" class="item">6</div>
        </div>

        <script src="flip.js"></script>
        <script>
            const container = document.getElementsByClassName("container")[0];
            let dragElem = null;
            let flip;

            container.ondragstart = function (e) {
                flip = new Flip(container.children, 0.5);
                dragElem = e.target;
                setTimeout(() => {
                    e.target.classList.add("moving");
                }, 0);
            }

            container.ondragover = function (e) {
                e.preventDefault();
            }

            container.ondragend = function (e) {
                e.target.classList.remove("moving");
            }

            container.ondragenter = function (e) {
                e.preventDefault();
                if (e.target === container || dragElem === e.target) {
                    return;
                }
                const children = [...container.children];
                const sourceIndex = children.indexOf(dragElem);
                const targetIndex = children.indexOf(e.target);
                if (sourceIndex > targetIndex) {
                    container.insertBefore(dragElem, e.target);
                } else {
                    container.insertBefore(dragElem, e.target.nextElementSibling);
                }
                flip.play();
            }
        </script>
    </body>
</html>

Flip工具类

javascript 复制代码

class Flip {
    children = null;
    delay = 0;

    constructor(children, delay = 1) {
        this.children = children;
        this.calculatePos();
        this.delay = delay;
    }

    calculatePos(name = "first") {
        const children = this.children;
        for (let i = 0; i < children.length; i++) {
            children[i][name] = children[i].getBoundingClientRect();
        }
    }

    play() {
        this.calculatePos("last");
        const children = this.children;
        for (let i = 0; i < children.length; i++) {
            const first = children[i]["first"];
            const last = children[i]["last"];
            if (first.x !== last.x || first.y !== last.y) {
                children[i].style.transform = `translateY(${first.y - last.y}px) translateX(${first.x - last.x}px)`;
                setTimeout(() => {
                    children[i].style.transition = `transform ${this.delay}s`;
                    children[i].style.removeProperty("transform");
                    setTimeout(() => {
                        children[i].style.removeProperty("transition");
                        this.calculatePos();
                    }, this.delay * 1000);
                }, 0);
            }
        }
    }
}

示例效果展示

拖拽功能展示