Mercurial > hg > index.fcgi > www > www-1

annotate pics3/static/lazyload.js @ 142:2ed8cf5f36bf

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myrss2: fix handling of null feed title or links; miscellaneous URL updates
author paulo
date Mon, 18 Dec 2023 20:10:27 +0000
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paulo@124 1 window.addEventListener('load', lazyLoadImages);
paulo@124 2 window.addEventListener('DOMContentLoaded', lazyLoadImages);
paulo@124 3 window.addEventListener('resize', lazyLoadImages);
paulo@124 4 window.addEventListener('scroll', lazyLoadImages);
paulo@124 5
paulo@124 6 function lazyLoadImages() {
paulo@124 7 var images = document.getElementsByTagName('img');
paulo@124 8 var loaded = 0;
paulo@124 9
paulo@124 10 for (var i = 0; i < images.length; i++) {
paulo@124 11 var img = images[i];
paulo@124 12 if (img.hasAttribute('data-src')) {
paulo@124 13 if (isElementInViewport(img)) {
paulo@124 14 img.setAttribute('src', img.getAttribute('data-src'));
paulo@124 15 img.removeAttribute('data-src');
paulo@124 16 }
paulo@124 17 } else {
paulo@124 18 loaded++;
paulo@124 19 }
paulo@124 20 }
paulo@124 21
paulo@124 22 //console.log('Loaded images:' + loaded + '/' + images.length);
paulo@124 23
paulo@124 24 if (loaded == images.length) {
paulo@124 25 //console.log('Loaded all images.');
paulo@124 26 window.removeEventListener('load', lazyLoadImages);
paulo@124 27 window.removeEventListener('DOMContentLoaded', lazyLoadImages);
paulo@124 28 window.removeEventListener('resize', lazyLoadImages);
paulo@124 29 window.removeEventListener('scroll', lazyLoadImages);
paulo@124 30 }
paulo@124 31 }
paulo@124 32
paulo@124 33 function isElementInViewport(el) {
paulo@124 34 var rect = el.getBoundingClientRect();
paulo@124 35
paulo@124 36 return (
paulo@124 37 rect.top >= 0 &&
paulo@124 38 rect.left >= 0 &&
paulo@124 39 rect.top <= window.innerHeight &&
paulo@124 40 rect.left <= window.innerWidth
paulo@124 41 );
paulo@124 42 }