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use-scroll-position

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https://bmgaynor.gitlab.io/use-scroll-position/#/

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import { useEffect, useState } from 'react'; var slicedToArray = function () { function sliceIterator(arr, i) { var _arr = []; var _n = true; var _d = false; var _e = undefined; try { for (var _i = arr[Symbol.iterator](), _s; !(_n = (_s = _i.next()).done); _n = true) { _arr.push(_s.value); if (i && _arr.length === i) break; } } catch (err) { _d = true; _e = err; } finally { try { if (!_n && _i["return"]) _i["return"](); } finally { if (_d) throw _e; } } return _arr; } return function (arr, i) { if (Array.isArray(arr)) { return arr; } else if (Symbol.iterator in Object(arr)) { return sliceIterator(arr, i); } else { throw new TypeError("Invalid attempt to destructure non-iterable instance"); } }; }(); var useScrollPosition = function useScrollPosition() { var _useState = useState(0), _useState2 = slicedToArray(_useState, 2), scrollPosition = _useState2[0], setScrollPosition = _useState2[1]; useEffect(function () { var last_known_scroll_position = 0; var ticking = false; var handleScroll = function handleScroll(e) { last_known_scroll_position = window.scrollY; if (!ticking) { window.requestAnimationFrame(function () { setScrollPosition(last_known_scroll_position); ticking = false; }); ticking = true; } }; window.addEventListener('scroll', handleScroll); return function () { window.removeEventListener('scroll', handleScroll); }; }); return scrollPosition; }; export default useScrollPosition; //# sourceMappingURL=index.es.js.map