aboutsummaryrefslogtreecommitdiff
path: root/vnext/src/components/Header.js
diff options
context:
space:
mode:
Diffstat (limited to 'vnext/src/components/Header.js')
-rw-r--r--vnext/src/components/Header.js69
1 files changed, 0 insertions, 69 deletions
diff --git a/vnext/src/components/Header.js b/vnext/src/components/Header.js
deleted file mode 100644
index 48f89360..00000000
--- a/vnext/src/components/Header.js
+++ /dev/null
@@ -1,69 +0,0 @@
-import React, { useEffect, useCallback, useRef } from 'react';
-import ReactDOM from 'react-dom';
-import PropTypes from 'prop-types';
-
-const elClassHidden = 'header--hidden';
-
-const header = document.getElementById('header');
-header.removeChild(document.getElementById('header_wrapper'));
-
-export default function Header({ children }) {
- let dHeight = useRef(0);
- let wHeight = useRef(0);
- let wScrollCurrent = useRef(0);
- let wScrollBefore = useRef(0);
- let wScrollDiff = useRef(0);
-
- useEffect(() => {
- window.addEventListener('scroll', () => (!window.requestAnimationFrame)
- ? throttle(250, updateHeader)
- : window.requestAnimationFrame(updateHeader), false);
- }, [updateHeader]);
- let throttle = (delay, fn) => {
- var last, deferTimer;
- return function () {
- var context = this, args = arguments, now = +new Date;
- if (last && now < last + delay) {
- clearTimeout(deferTimer);
- deferTimer = setTimeout(
- function () {
- last = now;
- fn.apply(context, args);
- },
- delay);
- } else {
- last = now;
- fn.apply(context, args);
- }
- };
- };
- let updateHeader = useCallback(() => {
- dHeight.current = document.body.offsetHeight;
- wHeight.current = window.innerHeight;
- wScrollCurrent.current = window.pageYOffset;
- wScrollDiff.current = wScrollBefore.current - wScrollCurrent.current;
-
- if (wScrollCurrent.current <= 0) {
- // scrolled to the very top; element sticks to the top
- header.classList.remove(elClassHidden);
- } else if (wScrollDiff > 0 && header.classList.contains(elClassHidden)) {
- // scrolled up; element slides in
- header.classList.remove(elClassHidden);
- } else if (wScrollDiff.current < 0) {
- // scrolled down
- if (wScrollCurrent.current + wHeight.current >= dHeight.current && header.classList.contains(elClassHidden)) {
- // scrolled to the very bottom; element slides in
- header.classList.remove(elClassHidden);
- } else {
- // scrolled down; element slides out
- header.classList.add(elClassHidden);
- }
- }
- wScrollBefore.current = wScrollCurrent.current;
- }, []);
- return ReactDOM.createPortal(children, header);
-}
-
-Header.propTypes = {
- children: PropTypes.node
-};