切换按钮JavaScript代码在React JS中不起作用

Question

我只想在JavaScript代码下面的注释部分寻求帮助。我想使用切换按钮/汉堡包按钮，但它不起作用，因为ReactJS不需要addEventListener。必须对哪些代码进行编码？非常感谢。

我正在做一个Traversy媒体教程使用Tailwind CSS。我想使用React作为框架，因为它具有可组合的组件特性和使用效率。

import React from 'react';
import logo from '../images/logo.svg';
// const btn = document.getElementById('menu-btn')
// const nav = document.getElementById('menu')
// btn.addEventListener('click', () => {
//   btn.classList.toggle('open')
//   nav.classList.toggle('flex')
//   nav.classList.toggle('hidden')
// })
const Navbar = () => {
return (
<div>
<nav className='relative container mx-auto p-6'>
{/* Flex Container */}
<div className='flex items-center justify-between'>
{/* Logo */}
<div className='pt-2'>
<img src={logo} alt='logo.svg'></img>
</div>
{/* Menu Items */}
<div className='hidden space-x-6 md:flex'>
<a href='/' className='hover:text-darkGrayishBlue'>
Pricing
</a>
<a href='/' className='hover:text-darkGrayishBlue'>
Product
</a>
<a href='/' className='hover:text-darkGrayishBlue'>
About Us
</a>
<a href='/' className='hover:text-darkGrayishBlue'>
Careers
</a>
<a href='/' className='hover:text-darkGrayishBlue'>
Community
</a>
</div>
{/* Button */}
<div>
<a
href='/'
className='hidden p-3 px-6 pt-2 text-white bg-brightRed rounded-full baseline hover:bg-brightRedLight md:block'
>
Get Started
</a>
</div>
{/* Hambuger Icon */}
<button
id='menu-btn'
className='block hamburger md:hidden focus:outline-none'
>
<span className='hamburger-top'></span>
<span className='hamburger-middle'></span>
<span className='hamburger-bottom'></span>
</button>
</div>
{/* Mobile Menu */}
<div className='md:hidden'>
<div
id='menu'
className='absolute flex-col items-center hidden self-end  py-8 mt-10 space-y-6 font-bold bg-white sm:w-auto sm:self-center left-6 right-6 drop-shadow-md'
>
<a href='/'>Pricing</a>
<a href='/'>Product</a>
<a href='/'>About</a>
<a href='/'>Careers</a>
<a href='/'>Community</a>
</div>
</div>
</nav>
</div>
);
};
export default Navbar;

Answer 1

您可以为按钮定义一个open状态和一个点击侦听器
然后根据open标志更改对象的类别：

import React from 'react';
import logo from '../images/logo.svg';
const Navbar = () => {
const [open, setOpen] = useState(false);
const handleMenuClick = () => {
setOpen((prev) => !prev);
};
return (
<div>
<nav className='relative container mx-auto p-6'>
{/* Flex Container */}
<div className='flex items-center justify-between'>
{/* ... */}
{/* Hambuger Icon */}
<button
id='menu-btn'
className={`block hamburger md:hidden focus:outline-none ${
open && 'open'
}`}
onClick={() => handleMenuClick()}
>
<span className='hamburger-top'></span>
<span className='hamburger-middle'></span>
<span className='hamburger-bottom'></span>
</button>
</div>
{/* Mobile Menu */}
<div className='md:hidden'>
<div
id='menu'
className={`absolute flex-col items-center hidden self-end  py-8 mt-10 space-y-6 font-bold bg-white sm:w-auto sm:self-center left-6 right-6 drop-shadow-md ${
open ? 'flex' : 'hidden'
}`}
>
<a href='/'>Pricing</a>
<a href='/'>Product</a>
<a href='/'>About</a>
<a href='/'>Careers</a>
<a href='/'>Community</a>
</div>
</div>
</nav>
</div>
);
};
export default Navbar;
```

Answer 2

您需要在定义按钮的地方定义事件处理。在你的情况下，它看起来像这样：

<button
id='menu-btn'
className='block hamburger md:hidden focus:outline-none'
onClick={doAction}>
>

react中有关事件处理的官方文件。