Update style of a component onScroll in React.js

In React.js, updating the style of a component based on scroll events can be achieved by utilizing the onScroll event and manipulating the component’s state. This allows for dynamic styling based on the user’s interaction with the page.

Solution 1: Using CSS classes and state

One approach is to define different CSS classes for the component’s styles and update the state of the component based on the scroll position. Here’s an example:

{`
import React, { useState } from 'react';
import './Component.css';

const Component = () => {
  const [isScrolled, setIsScrolled] = useState(false);

  const handleScroll = () => {
    const scrollPosition = window.scrollY;
    setIsScrolled(scrollPosition > 0);
  };

  window.addEventListener('scroll', handleScroll);

  return (
    
      {/* Component content */}
    
  );
};

export default Component;
  `}

In this example, we define a CSS class called scrolled which contains the desired styles for the component when it is scrolled. We use the isScrolled state variable to conditionally apply this class to the component based on the scroll position.

Solution 2: Using inline styles and state

If you prefer to use inline styles instead of CSS classes, you can modify the component’s style directly using the style prop. Here’s an example:

{`
import React, { useState } from 'react';

const Component = () => {
  const [componentStyle, setComponentStyle] = useState({});

  const handleScroll = () => {
    const scrollPosition = window.scrollY;
    setComponentStyle({ backgroundColor: scrollPosition > 0 ? 'red' : 'blue' });
  };

  window.addEventListener('scroll', handleScroll);

  return (
    
      {/* Component content */}
    
  );
};

export default Component;
  `}

In this example, we define the componentStyle state variable as an object that represents the component’s style. We update this object based on the scroll position, changing the background color to red when scrolled and blue when not scrolled.

Conclusion

Updating the style of a component on scroll in React.js can be achieved by utilizing the onScroll event and manipulating the component’s state. Whether you choose to use CSS classes or inline styles, both solutions provide a way to dynamically update the component’s style based on the user’s interaction with the page.

Update style of a component onScroll in React.js