window-onscroll

Usage

Get it from npm:

npm install window-onscroll

Import it and use it:

import ScrollManager from 'window-onscroll';

const sm = new ScrollManager();

console.log(sm.getScrollPosition());
// -> { scrollPositionX: 0, scrollPositionY: 0 }

window.addEventListener('window-scroll', function (e) {
  console.log('Vertical scroll position is: ' + e.detail.scrollPositionY);
  console.log('Horizontal scroll position is: ' + e.detail.scrollPositionX);

  requestAnimationFrame(function () {
    // repaint logic goes here
    // example:
    // rotateDiv.style.transform = 'rotate(' + e.detail.scrollPositionY / 2 + 'deg)';
  });
});

Browser support

<script src="https://unpkg.com/window-onscroll/dist/esm/index.js"></script>
<script>
  var sm = new ScrollManager();

  var valueDiv = document.querySelector('.ScrollPosition-value');
  var rotateDiv = document.querySelector('.ScrollPosition-rotate');

  window.addEventListener('window-onscroll', function (e) {
    requestAnimationFrame(function () {
      valueDiv.innerHTML = parseInt(e.detail.scrollPositionY, 10);
      rotateDiv.style.transform = 'rotate(' + e.detail.scrollPositionY / 2 + 'deg)';
    });
  });
</script>

API

• getScrollPosition() - returns current window scroll position object.

  {
    scrollPositionX: 0,
    scrollPositionY: 100,
  }

• removeListener() - reduces internal reference counter by one, and if it reaches 0 destroys the instance. Reference counter is increased every time new ScrollManager is called. For example, this is useful when scroll manager is used in React high order component (to track if any component is still using it). Use with caution.
• destroy() - destroys the singleton instance and removes scroll listener. Use with caution, call removeListener do this for you.