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Javascript – stop the scroll event listener in React.js

I’m trying to stop listening to the scroll event because I need to control when the event should scroll and when to remove the scroll event.

I’m trying to e.prevent but it doesnot work. Is there any way to controll the scroll by using react-js?

const handleScroll = (e) => {
        //I need to stop scrolling when a certain condition is true
        if (e.target.scrollHeight == 0) {
            // e.removeEventListener('scroll', handleScroll); DOES NOT WORK
            //e.pree.preventdefault() DOES NOT WORK    
        } else {
            //Turn on the listenner
        }
       
    }

    return (
        <main onScroll={handleScroll}data-status={valor}>
              <div>Conteudo</div> 
        </main >
    );

If you guys can help me i really appreciate it. Thanks for all, Have a good day.

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2

Answers


  1. 0

    Try with this Code :

    import React, { useEffect, useRef } from 'react';

const ExampleComponent = () => {
  const shouldEnableScroll = useRef(true);

  const handleScroll = (e) => {
    if (!shouldEnableScroll.current) {
      e.preventDefault(); // Prevent scrolling when shouldEnableScroll is false
    }

    // Your scrolling logic here
    if (e.target.scrollHeight === 0) {
      // Set shouldEnableScroll to false when a certain condition is true
      shouldEnableScroll.current = false;
    } else {
      // Set shouldEnableScroll to true when the condition is false
      shouldEnableScroll.current = true;
    }
  };

  useEffect(() => {
    // Add scroll event listener when the component mounts
    document.addEventListener('scroll', handleScroll);

    // Remove scroll event listener when the component unmounts
    return () => {
      document.removeEventListener('scroll', handleScroll);
    };
  }, []); // Empty dependency array means this effect runs once when the component mounts

  return (
    <main onScroll={handleScroll} data-status={shouldEnableScroll.current ? 'enabled' : 'disabled'}>
      <div>Conteudo</div>
    </main>
  );
};

export default ExampleComponent;
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  2. 0

    Here’s how you might implement this:

    import React, { useState, useEffect } from 'react';
import './App.css'; // Ensure you have the correct path to your CSS file

const ExampleComponent = () => {
  const [isScrollEnabled, setIsScrollEnabled] = useState(true);

  const handleScroll = (e) => {
    // Your condition to disable scrolling
    if (/* your condition here */) {
      setIsScrollEnabled(false);
    } else {
      setIsScrollEnabled(true);
    }
  };

  useEffect(() => {
    // Add scroll event listener when the component mounts
    window.addEventListener('scroll', handleScroll);

    // Clean up the event listener when the component unmounts
    return () => window.removeEventListener('scroll', handleScroll);
  }, []); // The empty array causes this effect to only run on mount and unmount

  return (
    <main className={isScrollEnabled ? '' : 'disable-scrolling'} onScroll={handleScroll}>
      <div>Content</div>
    </main>
  );
};

export default ExampleComponent;

    In your CSS (App.css):

    .disable-scrolling {
  overflow: hidden;
  height: 100%; /* Or a specific height as needed */
}

    This method uses a state variable to track whether scrolling should be enabled and applies a CSS class to control the actual scrolling. It’s a more React-centric way of handling this issue, fitting well with the declarative nature of React. Additionally, it’s a good practice to clean up event listeners when the component unmounts to avoid memory leaks and unexpected behavior, which is handled in the useEffect cleanup function.

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