react-behave/build/es/watchResize/watchResize.js

A library of behaviors for React applications.

import throttle from 'lodash.throttle';
import ResizeObserver from 'resize-observer-polyfill'; // Corresponds to 1 frame

var DEFAULT_RESIZE_INTERVAL = 16;
export function watchResize(target, cb) {
  var _ref = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : {},
      _ref$resizeInterval = _ref.resizeInterval,
      resizeInterval = _ref$resizeInterval === void 0 ? DEFAULT_RESIZE_INTERVAL : _ref$resizeInterval;

  function handleResize(entries) {
    if (entries.length) {
      cb(entries[0].contentRect);
    }
  }

  var observer = throttle(handleResize, resizeInterval);
  var resizeObserver = new ResizeObserver(observer);
  resizeObserver.observe(target);
  return function () {
    observer.cancel();
    resizeObserver.unobserve(target);
  };
}