react 可拖拽静态组件

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import { useRef } from "react";
import clamp from "lodash-es/clamp";
import swap from "lodash-move";
import { useSprings, animated, config } from "@react-spring/web";
import { useDrag } from "@use-gesture/react";
import { MAX_COL, SX, SY } from "@/constants/combFile";
import "./index.css";

const OperatePic = ({ items }) => {
    const height = (Math.floor(items.length / MAX_COL) + 1) * SY;
    const width =
        (Math.floor(items.length / MAX_COL) >= 1 ? MAX_COL : items.length) * SX;

    // 创建两个springs，一个用于拖动时的动画参数，一个用于没有拖动时平移的参数
    const fn =
        (
            order,
            active = false,
            originalIndex = 0,
            curIndex = 0,
            x = 0,
            y = 0
        ) =>
        (index) =>
            active && index === originalIndex
                ? {
                      x: (curIndex % MAX_COL) * SX + x,
                      y: Math.floor(curIndex / MAX_COL) * SY + y,
                      scale: 1.1,
                      zIndex: 1,
                      shadow: 15,
                      immediate: (key) => key === "zIndex",
                      config: (key) =>
                          key === "y" ? config.stiff : config.default,
                  }
                : {
                      x: (order.indexOf(index) % MAX_COL) * SX,
                      y: Math.floor(order.indexOf(index) / MAX_COL) * SY,
                      scale: 1,
                      zIndex: 0,
                      shadow: 1,
                      immediate: false,
                  };

    const order = useRef(items.map((_, index) => index)); // 将索引存储为本地引用，这表示项目顺序，将在拖动时更新
    const [springs, api] = useSprings(items.length, fn(order.current)); // 创建spring，每个spring对应一个项目，控制其变形、缩放等。
    const bind = useDrag(
        ({ args: [originalIndex], active, movement: [x, y] }) => {
            const curIndex = order.current.indexOf(originalIndex); // 获取当前拖动的元素所在的索引位置
            const curRow = clamp(
                // 获取当前拖动的元素所在的行数
                Math.round((Math.floor(curIndex / MAX_COL) * SY + y) / SY),
                0,
                Math.floor(items.length / MAX_COL)
            );
            const curCol = clamp(
                // 获取当前拖动的元素所在的列数
                Math.round(((curIndex % MAX_COL) * SX + x) / SX),
                0,
                Math.max(items.length - 1, MAX_COL)
            );
            console.log(curRow, curCol, curIndex, originalIndex, x, y);
            const newOrder = swap(
                order.current,
                curIndex,
                curRow * MAX_COL + curCol
            ); //  交换当前拖动的元素和目标位置的元素的索引，得到新的索引顺序
            api.start(fn(newOrder, active, originalIndex, curIndex, x, y)); // 可以在不依靠render的情况下，进行动画的更新
            if (!active) order.current = newOrder; // 如果拖动结束，更新索引顺序
        }
    );

    return (
        <div
            className="content"
            style={{
                height: height,
                width: width,
            }}
        >
            {springs.map(({ zIndex, shadow, x, y, scale }, i) => (
                <animated.div
                    {...bind(i)} // 绑定拖动事件
                    key={i} // 绑定key
                    style={{
                        width: SX - 20,
                        height: SY - 20,
                        // 与fn的返回值对应
                        zIndex,
                        boxShadow: shadow.to(
                            (s) =>
                                `rgba(0, 0, 0, 0.15) 0px ${s}px ${2 * s}px 0px`
                        ),
                        x,
                        y,
                        scale,
                    }}
                    children={items[i]} // 显示内容
                />
            ))}
        </div>
    );
};

export default OperatePic;

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.content {
    width: 320px;
}

.content > div {
    position: absolute;
    border-radius: 10px;
    font-size: 14.5px;
    background: hsla(0, 0%, 90%, 0.8);
    touch-action: none;
    cursor: grab;
    border-right: 0;
    border-bottom: 0;
    box-shadow: 5px 5px 5px -4px rgba(180, 160, 120, 0.6);
}

.content > div:hover {
    cursor: grabbing;
}