react-visibility-detector v1.1.1

React visibility detector

A React component that notifies you when it enters or exits the viewport. Based on a IntersectionObserver, resulting in improved performance. Not supported by IE and some others, see here - https://caniuse.com/?search=IntersectionObserver

Install

yarn add react-visibility-detector

Example

To run the example locally:

• yarn build
• cd example
• yarn
• yarn start
• open http://localhost:1234 in your browser

General usage goes something like:

import VisibilityDetector from 'react-visibility-detector';

function handleVisibilityChange ({ visible, directionX, directionY }) {
  console.log('Element is now %s', visible ? 'visible' : 'hidden');
  console.log('Horizontal direction %s', directionX); // left, right, or none if no changed or initial
  console.log('Vertical direction %s', directionY); // up, down or none if no changed or initial
}

function MyComponent (props) {
  return (
    <VisibilityDetector onVisibilityChange={handleVisibilityChange}>
      <div>...content goes here...</div>
    </VisibilityDetector>
  );
}

// with hook

import { useChangeVisibility } from 'react-visibility-detector';

function onVisibilityChange ({ visible, directionX, directionY }) {
  console.log('Element is now %s', visible ? 'visible' : 'hidden');
  console.log('Horizontal direction %s', directionX); // left, right, or none if no changed or initial
  console.log('Vertical direction %s', directionY); // up, down or none if no changed or initial
}

function MyComponent (props) {
  const targetRef = useRef(null);
  useChangeVisibility({ targetRef, onVisibilityChange });

  return (
    <div ref={targetRef}>...content goes here...</div>
  );
}

Try it out

Run the example.

Props

• className css class for styling, default undefined
• distance - distance to the viewport at which the detector will trigger, default 0
• onVisibilityChange - callback, called when changed detector visibility
• children

Hook props

• distance - distance to the viewport at which the detector will trigger, default 0
• onVisibilityChange - callback, called when changed detector visibility
• targetRef - ref to target element

License

MIT