CODE EXAMPLE FOR JAVASCRIPT

How to create $(document).ready() for vanilla JavaScript

// You have 2 solution [1- simple that suport only new browsers]
document.addEventListener("DOMContentLoaded", function() {
  alert('dom is ready ^-^');
});
// [2- full solution that suport all browsers by using domready.js]
// step 1 - add to page head
<script>
(function(){var DomReady = window.DomReady = {};var userAgent = navigator.userAgent.toLowerCase();var browser = {version: (userAgent.match( /.+(?:rv|it|ra|ie)[/: ]([d.]+)/ ) || [])[1],safari: /webkit/.test(userAgent),opera: /opera/.test(userAgent),msie: (/msie/.test(userAgent)) && (!/opera/.test( userAgent )),mozilla: (/mozilla/.test(userAgent)) && (!/(compatible|webkit)/.test(userAgent))};var readyBound = false;var isReady = false;var readyList = [];function domReady() {if(!isReady) {isReady = true;if(readyList) {for(var fn = 0; fn < readyList.length; fn++) {readyList[fn].call(window, []);}readyList = [];}}};function addLoadEvent(func) {  var oldonload = window.onload;  if (typeof window.onload != 'function') {window.onload = func;  } else {window.onload = function() {  if (oldonload) {oldonload();  }  func();}  }};function bindReady() {if(readyBound) {return;}readyBound = true;if (document.addEventListener && !browser.opera) {document.addEventListener("DOMContentLoaded", domReady, false);}if (browser.msie && window == top) (function(){if (isReady) return;try {document.documentElement.doScroll("left");} catch(error) {setTimeout(arguments.callee, 0);return;}domReady();})();if(browser.opera) {document.addEventListener( "DOMContentLoaded", function () {if (isReady) return;for (var i = 0; i < document.styleSheets.length; i++)if (document.styleSheets[i].disabled) {setTimeout( arguments.callee, 0 );return;}domReady();}, false);}if(browser.safari) {var numStyles;(function(){if (isReady) return;if (document.readyState != "loaded" && document.readyState != "complete") {setTimeout( arguments.callee, 0 );return;}if (numStyles === undefined) {var links = document.getElementsByTagName("link");for (var i=0; i < links.length; i++) {if(links[i].getAttribute('rel') == 'stylesheet') {numStyles++;}}var styles = document.getElementsByTagName("style");numStyles += styles.length;}if (document.styleSheets.length != numStyles) {setTimeout( arguments.callee, 0 );return;}domReady();})();}addLoadEvent(domReady);};DomReady.ready = function(fn, args) {bindReady();if (isReady) {fn.call(window, []);} else {readyList.push( function() { return fn.call(window, []); } );}};bindReady();})();
</script>
// step 2 - use in your pages
<script>
DomReady.ready(function() {alert('dom is ready ^-^');});
</script>