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How to add `onscroll` event in ReactJS component
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import React from 'react'; | |
let lastScrollY = 0; | |
let ticking = false; | |
class App extends React.Component { | |
componentDidMount() { | |
window.addEventListener('scroll', this.handleScroll, true); | |
} | |
componentWillUnmount() { | |
window.removeEventListener('scroll', this.handleScroll); | |
} | |
nav = React.createRef(); | |
handleScroll = () => { | |
lastScrollY = window.scrollY; | |
if (!ticking) { | |
window.requestAnimationFrame(() => { | |
this.nav.current.style.top = `${lastScrollY}px`; | |
ticking = false; | |
}); | |
ticking = true; | |
} | |
}; | |
render() { | |
return ( | |
<div> | |
<nav ref={this.nav}> | |
</nav> | |
<div> | |
); | |
} | |
} | |
export default App; |
Is anyone having issues with the event returning as undefined?
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@raheemazeezabiodun Note, that if you use an arrow function syntax for declaring custom handlers, you won't need to bind them to
this
inside of a constructor function:vs