react tab选项卡吸顶实现

react  tab选项卡吸顶实现，直接上代码（代码有注释）

tsx代码

/* eslint-disable react-hooks/exhaustive-deps */
import React, { useEffect, useState } from "react";
import DocumentTitle from 'react-document-title'
import styles from './styles.module.less'

// 双旦活动
const Holiday: React.FC<any> = () => {
    const tabList = [
        {
            label:'礼物榜单',
            value:0
        },
        {
            label:'圣诞活动',
            value:1
        },
        {
            label:'元旦活动',
            value:2
        }
    ]
    const [active,setactive] = useState<number>(0)
    const [isFixed,setisFixed] = useState<boolean>(false)
    //获得页面向左、向上卷动的距离
    const getScroll = () => {
        return {
            left: window.pageXOffset || document.documentElement.scrollLeft || document.body.scrollLeft || 0,
            top: window.pageYOffset || document.documentElement.scrollTop || document.body.scrollTop || 0
        };
    }
  
    useEffect(() => {
        const btnList = document.getElementById('btnList')
        const offsetTop = btnList?.offsetTop || 0  // offsetTop：元素到offsetParent顶部的距离（当前元素顶部距离最近父元素顶部的距离）
        window.onscroll = function() {
            if(getScroll().top >= offsetTop){  // 判断滚动高度是否大于等于 btnList的offsetTop
                setisFixed(true)   // 用于判断是否给btnList动态设置style
            }else{
                setisFixed(false)
            }
        }
    }, [])


    return (
        <DocumentTitle title='双旦活动'>
            <div className={styles.Holiday}>
                <div className={styles.top}>
                    <div className={styles.btnList} id="btnList" style={isFixed ? { zIndex: "999",top: "0",position: "fixed", backgroundColor: "#fff" } : {}}>
                        {
                            tabList.map((item:any) => (
                                <div onClick={()=> setactive(item.value)} 
                                key={item.value}
                                className={active === item.value ? styles.acitve : ''}>
                                    {item.label}
                                </div>
                            ))
                        }
                    </div>
                </div>
                <div className={styles.center}>
                    <div className={styles.centerBox}>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                       <div>双旦活动</div>
                    </div>
                </div>
            </div>
        </DocumentTitle>
    )
}
export default Holiday;

less代码

.Holiday {
    width: 100%;
    height: 100%;
    position: relative;
    display: flex;
    flex-direction: column;
    .top{
        width: 100vw;
        height: 590px;
        background: url('../../assets/toplistbg.png') no-repeat;
        background-size: 100%;
        position: relative;
        .btnList{
            width: 100vw;
            padding: 20px 37px;
            box-sizing: border-box;
            position: absolute;
            bottom: 28px;
            height: 120px;
            display: flex;
            justify-content: space-between;
            bottom: 20px;
            >div{
                &.acitve{
                    background: rgba(1, 50, 82, 1);
                    color: #fff;
                }
                width: 212px;
                height: 80px;
                background: rgba(1, 50, 82, 0.1);
                border-radius: 40px;
                font-size: 30px;
                color: #333;
                display: flex;
                align-items: center;
                justify-content: center;
                font-family: PingFangSC-Regular, PingFang SC;
                font-weight: 400;
            }
        }
    }
    .center{
        width: 100vw;
        padding: 24px;
        box-sizing: border-box;
        .centerBox{
            width: 100%;
            background: #044067;
            border-radius: 20px;
            box-sizing: border-box;
            padding: 30px 28px;
            >div{
                color: #fff;
                font-size: 30px;
                text-align: center;
                line-height: 80px;
            }
        }
    }
}

效果展示