react使用react-window虚拟滚动实战

摘要：react-window插件一般用来和react-virtualized-auto-sizer配合使用，react-virtualized-auto-sizer负责获取父元素的宽度和高度，传入到List中，但实战时，往往有些列表用到了隐藏显示, 比方说disabled:none;当使用disabled为none时，react-virtualized-auto-sizer会移除子元素；当返回时，元素会重新渲染，滚动条也会滚到顶部;

备注：如果是’visibility: hidden;'子元素会保留，其仍然占用宽度和高度，实战中很多场景不适用，这里不展开讨论;本文主要讲自定义AutoSizer组件规避掉disabled:none的Bug;

项目依赖

"react": "^18.2.0",
"react-dom": "^18.2.0",
"react-window": "^1.8.9",
// 实用这个有bug所以自己封装了AutoSizer
"react-virtualized-auto-sizer": "^1.0.20",

日常使用

import AutoSizer from "@/views/Components/AzAutoSizer";
<AutoSizer>
    {({ height, width }: {height: number, width: number}) => (
        <List 
            height={height}
            itemCount={curMonitorList.length}
            itemSize={48}
            width={width}>
            {renderOrgItem}
        </List>
        )
    }
</AutoSizer>

封装AutoSizer

import { useEffect, useState, useRef } from "react";
interface PropsType{
    children: any
}
export default function AzAutoSizer({children}: PropsType) {
    const curRef = useRef<HTMLDivElement>(null)
    const [curWidthHeight, setCurWidthHeight] = useState({
        height: 0,
        width: 0,
    });
    const handleClick = () => {
        if (curRef.current) {
            const parentNode: any = curRef.current.parentNode;
            const height = parentNode.offsetHeight;
            const width = parentNode.offsetWidth;
            curWidthHeight.height = height || 0;
            curWidthHeight.width = width || 0;
            setCurWidthHeight({...curWidthHeight});
        }
    };
    useEffect(() => {
        handleClick();
        const handleResize = () => {
            if (!curRef.current) { return; }
            // const parentNode: any = curRef.current.parentNode;
            // const height = parentNode.offsetHeight
            // const width = parentNode.offsetWidth;
            // // 表示父或祖先disabled: none;
            // if (height === 0 && width === 0) {
            //     return;
            // }
            handleClick();
        };
        /* 窗口改变 */
        window.addEventListener('resize', handleResize);
        /* 是否可视化 */
        const observer = new IntersectionObserver(([{ isIntersecting }]) => {
            if (isIntersecting) {
                if (!curRef.current) { return; }
                if (curWidthHeight.height !== 0 && curWidthHeight.width !== 0) {
                    // observer.unobserve(curRef.current);
                } else {
                    console.log('可视化');
                    handleClick();
                }
            }
        });
        curRef.current && observer.observe(curRef.current);

        return () => {
            /* 窗口改变 */
            window.removeEventListener('resize', handleResize);
            /* 卸载 */
            if (curRef.current) {
                observer.unobserve(curRef.current);
            }

        };

    }, []);
    return <div ref={curRef} style={{width: `${curWidthHeight.width}px`, height: `${ curWidthHeight.height}px`}}>
        {children({height: curWidthHeight.height, width: curWidthHeight.width})}
    </div>
}