lazyload-js/LazyLoad.min.js

An ancient tiny JS and CSS loader from the days before everyone had written one, Fork from @github/rgrove/lazyload

LazyLoad=function(a){function h(b,c){var e,d=a.createElement(b);for(e in c)c.hasOwnProperty(e)&&d.setAttribute(e,c[e]);return d}function i(a){var c,g,b=d[a];b&&(c=b.callback,g=b.urls,g.shift(),e=0,g.length||(c&&c.call(b.context,b.obj),d[a]=null,f[a].length&&k(a)))}function j(){var c=navigator.userAgent;b={async:!0===a.createElement("script").async},(b.webkit=/AppleWebKit\//.test(c))||(b.ie=/MSIE|Trident/.test(c))||(b.opera=/Opera/.test(c))||(b.gecko=/Gecko\//.test(c))||(b.unknown=!0)}function k(e,g,k,n,o){var s,t,u,v,w,x,p=function(){i(e)},q="css"===e,r=[];if(b||j(),g)if(g="string"==typeof g?[g]:g.concat(),q||b.async||b.gecko||b.opera)f[e].push({urls:g,callback:k,obj:n,context:o});else for(s=0,t=g.length;s<t;++s)f[e].push({urls:[g[s]],callback:s===t-1?k:null,obj:n,context:o});if(!d[e]&&(v=d[e]=f[e].shift())){for(c||(c=a.head||a.getElementsByTagName("head")[0]),w=v.urls.concat(),s=0,t=w.length;s<t;++s)x=w[s],q?u=b.gecko?h("style"):h("link",{href:x,rel:"stylesheet"}):(u=h("script",{src:x}),u.async=!1),u.className="lazyload",u.setAttribute("charset","utf-8"),b.ie&&!q&&"onreadystatechange"in u&&!("draggable"in u)?u.onreadystatechange=function(){/loaded|complete/.test(u.readyState)&&(u.onreadystatechange=null,p())}:q&&(b.gecko||b.webkit)?b.webkit?(v.urls[s]=u.href,m()):(u.innerHTML='@import "'+x+'";',l(u)):u.onload=u.onerror=p,r.push(u);for(s=0,t=r.length;s<t;++s)c.appendChild(r[s])}}function l(a){var b;try{b=!!a.sheet.cssRules}catch(c){return e+=1,void(e<200?setTimeout(function(){l(a)},50):b&&i("css"))}i("css")}function m(){var b,a=d.css;if(a){for(b=g.length;--b>=0;)if(g[b].href===a.urls[0]){i("css");break}e+=1,a&&(e<200?setTimeout(m,50):i("css"))}}var b,c,d={},e=0,f={css:[],js:[]},g=a.styleSheets;return{css:function(a,b,c,d){k("css",a,b,c,d)},js:function(a,b,c,d){k("js",a,b,c,d)}}}(this.document);