How to add `onscroll` event in ReactJS component

App.js

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;

@paintedbicycle Thank you!! This worked for me

Thanks this is exactly what I needed to do for a ShadowDOM supported div that used onScroll.
Turns out ShadowDOM does not support scroll listener, it's essentially blocked.

What I did was:

const listNode = ReactDOM.findDOMNode(this.list);
listNode.addEventListener('scroll', this.handleScroll);

and it worked! 🎉

If anyone is thinking they are going crazy that it's not working for them, while everyone else is piling on saying it does, try this:

  componentDidMount() {
    window.addEventListener('scroll', this.handleScroll, true);
  }

Note, the third argument of "true".

https://developer.mozilla.org/en-US/docs/Web/API/EventTarget/addEventListener

Worked for me

thank you very much @paintedbicycle

This worked for me:

constructor(props) {
  super(props);
  this.handleScroll = this.handleScroll.bind(this);
}

componentDidMount() {
  window.addEventListener('scroll', this.handleScroll);
};

componentWillUnmount() {
  window.removeEventListener('scroll', this.handleScroll);
};

handleScroll(event) {
  console.log('the scroll things', event)
};

your solution worked for me. Thank you for this

@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:

constructor(props) {
  supert(props);
  this.handleScroll = this.handleScroll.bind(this);
}

handleScroll(event) { ... };

vs

handleScroll = (event) => { ... };

Is anyone having issues with the event returning as undefined?