Question

我的导航栏有问题。当它位于顶部时，它应该是透明的并且字体颜色为白色，只要用户稍微滚动一下，导航栏的背景就会变成白色，字体颜色应该变成黑色。这也适用于移动视图。菜单图标未显示为黑色，如果我在顶部（导航栏为透明色），则移动菜单也可以正确显示，但是如果我向下滚动一点并且移动导航栏显示在白色，移动导航栏以黑色字体显示，不应该如此。我该如何解决这个问题？

顶部导航栏透明

导航栏滚动并显示为白色

移动视图 顶部透明的移动导航栏

顶部和透明的移动导航栏以及当您打开菜单时

导航栏滚动并呈白色

导航栏滚动并显示为白色，然后您打开菜单

菜单栏应该和上图中的完全一样，图标应该是黑色的，如图4

代码

Navbar.js

import React, { useState, useEffect } from "react";
import { Button } from "../buttons/Button";
import { Link } from "react-router-dom";
import "./Navbar.css";

function Navbar() {
  const [click, setClick] = useState(false);
  const [button, setButton] = useState(true);
  const [navbar, setNavbar ] = useState(false);

  const handleClick = () => setClick(!click);
  const closeMobileMenu = () => setClick(false);

  const showButton = () => {
    if (window.innerWidth <= 960) {
      setButton(false);
    } else {
      setButton(true);
    }
  };

  useEffect(() => {
    showButton();
  }, []);

  window.addEventListener("resize", showButton);

  const changeBackground = () => {
    if(window.scrollY >= 80) {
        setNavbar(true);
    }
    else {
        setNavbar(false);
    }
};

window.addEventListener('scroll', changeBackground);



  return (
    <>
      <nav className={navbar ? 'navbar active' : 'navbar'}>
        <div className="navbar-container">
          <Link to="/" className={navbar ? 'navbar-logo active' : 'navbar-logo'} onClick={closeMobileMenu}>
            NAME
            <i class="fab fa-typo3" />
          </Link>
          <div className="menu-icon" onClick={handleClick}>
            <i className={click ? "fas fa-times" : "fas fa-bars"} />
          </div>
          <ul className={click ? "nav-menu active" : "nav-menu"}>
            <li className="nav-item">
              <Link to="/" className={navbar ? 'nav-links active' : 'nav-links'} onClick={closeMobileMenu}>
                Text 1
              </Link>
            </li>
            <li className="nav-item">
              <Link
                to="/"
                className={navbar ? 'nav-links active' : 'nav-links'}
                onClick={closeMobileMenu}
              >
                Text 2
              </Link>
            </li>
            <li className="nav-item">
              <Link
                to="/"
                className={navbar ? 'nav-links active' : 'nav-links'}
                onClick={closeMobileMenu}
              >
                Text 3
              </Link>
            </li>

            <li>
              <Link
                to="/"
                className="nav-links-mobile"
                onClick={closeMobileMenu}
              >
                BUTTON
              </Link>
            </li>
          </ul>
          {button && <Button buttonStyle="btn--primary">BUTTON</Button>}
        </div>
      </nav>
    </>
  );
}

export default Navbar;

Navbar.css

.navbar {
    /*background: #2b41cb;*/
    background: transparent;
    height: 80px;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 1.2rem;
    position: sticky;
    top: 0;
    z-index: 999;
    margin-bottom: -80px;
  }
 

  .navbar-container {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 80px;
    max-width: 1500px;
  }

  
  
  .navbar-logo {
    color: #fff;
    justify-self: start;
    margin-left: 20px;
    cursor: pointer;
    text-decoration: none;
    font-size: 2rem;
    display: flex;
    align-items: center;
  }

  
  .fa-typo3 {
    margin-left: 0.5rem;
    font-size: 1.8rem;
  }
  
  .nav-menu {
    display: grid;
    grid-template-columns: repeat(4, auto);
    grid-gap: 10px;
    list-style: none;
    text-align: center;
    width: 60vw;
    justify-content: end;
    margin-right: 2rem;
  }
  
  .nav-item {
    height: 80px;
  }
  
  .nav-links {
    color: #fff;
    display: flex;
    align-items: center;
    text-decoration: none;
    padding: 0.5rem 1rem;
    height: 100%;
  }
  
  .nav-links:hover {
    border-bottom: 4px solid #fff;
    transition: all 0.2s ease-out;
  }
  
  .fa-bars {
    color: #fff;
  }
  
  .nav-links-mobile {
    display: none;
  }
  
  .menu-icon {
    display: none;
  }
  
  @media screen and (max-width: 960px) {
    .NavbarItems {
      position: relative;
    }
  
    .nav-menu {
      display: flex;
      flex-direction: column;
      width: 100%;
      height: 90vh;
      position: absolute;
      top: 80px;
      left: -100%;
      opacity: 1;
      transition: all 0.5s ease;
    }
  
    .nav-menu.active {
      background: #242222;
      left: 0;
      opacity: 1;
      transition: all 0.5s ease;
      z-index: 1;
    }
  
    .nav-links {
      text-align: center;
      padding: 2rem;
      width: 100%;
      display: table;
    }
  
    .nav-links:hover {
      background-color: #fff;
      color: #242424;
      border-radius: 0;
    }
  
    .navbar-logo {
      position: absolute;
      top: 0;
      left: 0;
      transform: translate(25%, 50%);
    }
  
    .menu-icon {
      display: block;
      position: absolute;
      top: 0;
      right: 0;
      transform: translate(-100%, 60%);
      font-size: 1.8rem;
      cursor: pointer;
    }
  
    .fa-times {
      color: #fff;
      font-size: 2rem;
    }
  
    .nav-links-mobile {
      display: block;
      text-align: center;
      margin: 2rem auto;
      border-radius: 4px;
      width: 80%;
      text-decoration: none;
      font-size: 1.5rem;
      background-color: goldenrod;
      color: #fff;
      padding: 14px 20px;
      border: 1px solid goldenrod;
      transition: all 0.3s ease-out;
      border-radius: 25px;
    }
  
    .nav-links-mobile:hover {
      background: goldenrod;
      transition: 250ms;
    }
  }

  /* NAVBAR ACTIVE */
   
  .navbar.active {
    /*background: linear-gradient(90deg, rgb(66, 2, 194) 0%, rgb(0, 78, 194) 100%)*/
    background: #fff;
    border-bottom: 2px solid #e8e8e8;
  }
  

  .navbar-logo.active {
    color: #000;
  }


  .nav-links.active {
    color: #000;
  }

  .nav-links.active:hover {
    border-bottom: 4px solid #000;
    transition: all 0.2s ease-out;
  }

不是必须的，但要让它运行

HeroSection.js

import React from 'react';
import '../../App.css';
import { Button } from '../buttons/Button';
import './HeroSection.css';



function HeroSection() {



  return (
    <div className='hero-container'>
      <h1>Heading One</h1>
      <p>Some Text!</p>
      <div className='hero-btns'>
        <Button
          className='btns'
          buttonStyle='btn--outline'
          buttonSize='btn--large'
        >
          BUTTON 1
        </Button>
        <Button
          className='btns'
          buttonStyle='btn--primary'
          buttonSize='btn--large'
        >
          BUTTON 2 <i className='far fa-arrow-alt-circle-right' />
        </Button>
      </div>
    </div>
  );
}

export default HeroSection;

HeroSection.css

video {
    object-fit: cover;
    width: 100%;
    height: 100%;
    position: fixed;
    z-index: -1;
  }
  
  .hero-container {
    background: rgba(102, 232, 255, 0.849);
    height: 100vh;
    width: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    /*box-shadow: inset 0 0 0 1000px rgba(0, 0, 0, 0.2);*/
    object-fit: contain;
  }
  
  .hero-container > h1 {
    color: #fff;
    font-size: 100px;
    margin-top: -100px;
  }
  
  .hero-container > p {
    margin-top: 8px;
    color: #fff;
    font-size: 32px;
    font-family: 'Trebuchet MS', 'Lucida Sans Unicode', 'Lucida Grande',
      'Lucida Sans', Arial, sans-serif;
  }
  
  .hero-btns {
    margin-top: 32px;
  }
  
  .hero-btns .btn {
    margin: 6px;
  }
  
  .fa-play-circle {
    margin-left: 4px;
  }
  
  @media screen and (max-width: 960px) {
    .hero-container > h1 {
      font-size: 70px;
      margin-top: -150px;
    }
  }
  
  @media screen and (max-width: 768px) {
    .hero-container > h1 {
      font-size: 50px;
      margin-top: -100px;
    }
  
    .hero-container > p {
      font-size: 30px;
    }
  
    .btn-mobile {
      display: block;
      text-decoration: none;
    }
  
    .btn {
      width: 100%;
    }
  }

Home.js

import React from 'react';
import '../../App.css';
import Cards from '../cards/Cards';
import Footer from '../footer/Footer';
import HeroSection from '../Hero/HeroSection';
import Box from '../box/Box';

function Home() {
    return (
        <>
            <HeroSection></HeroSection>
            
        </>
    )
}

export default Home;

App.js

import React from 'react'
import Navbar from './components/navbar/Navbar'
import { BrowserRouter as Router, Switch, Route } from 'react-router-dom';
import Home from './components/pages/Home';
import './App.css'


function App() {
  return (
    <>
      <Router>
      <Navbar/>
      <Switch>
          <Route path='/' exact component={Home} />
      </Switch>
      </Router>
    </>
  );
}

export default App;

Answer 1

可能你需要不同的类为你在不同的情况下动态添加不同的导航按钮:)

Answer 2

window.addEventListener("resize", showButton);

  const changeBackground = () => {
     let scrollClass = '';
    if(window.scrollY >= 80) {
        setNavbar(true);
        scrollClass = 'black';
    }
    else {
        setNavbar(false);
        scrollClass = '';
    }
    this.setState({ scrollClass });

<div className="menu-icon" onClick={handleClick}>
     <i className={`click ? "fas fa-times" : "fas fa-bars" ${this.state.scrollClass }`} />
</div>

滚动和移动视图中导航栏显示不正确

2 个答案: