https://studentpool.nl/wp-content/themes/bz-studentpool/assets/essentials/es-loader.js

1/**
2 * Plugin Name: jQuery Essentials Loader
3 * Version: 1.0
4 * Date: 10-07-2017
5 * License: CC0 1.0 (https://creativecommons.org/publicdomain/zero/1.0/deed)
6 * 
7**/
8
9function showLoader() {
10    jQuery('body').addClass('loading').addClass('loading-inline');
11    var requestAnimationFrame = window.requestAnimationFrame || window.mozRequestAnimationFrame || window.webkitRequestAnimationFrame || window.msRequestAnimationFrame;
12    if (typeof requestAnimationFrame !== 'undefined') {
13        window.requestAnimationFrame(function () {
14        });
15    }
16}
17
18function hideLoader(){
19    jQuery('body').removeClass('loading').removeClass('loading-inline').addClass('loaded');
20    jQuery('.loader-div').fadeOut(250);
21}
22
23var ignore_onbeforeunload = false;
24jQuery('body').on('click', 'a[href^=mailto], a[href^=tel]', function () {
25    ignore_onbeforeunload = true;
26});
27
28function showPage(e) {
29    if (typeof e !== 'undefined' && typeof e.persisted !== 'undefined' && e.persisted) {
30        window.location.reload();
31    }
32    hideLoader();
33}
34
35function hidePage(e) {
36    if (!ignore_onbeforeunload) {
37        showLoader();
38    }
39    ignore_onbeforeunload = false;
40}
41
42window.addEventListener("pageshow", showPage, false);
43jQuery(window).on('load', showPage);
44
45window.addEventListener("pagehide", hidePage, false);
46jQuery(window).on('beforeunload', hidePage);
47jQuery(window).on('unload', hidePage);