GettingToKnowMutationObservers/mutationobserver-mutationobserver.html at master · webinista/GettingToKnowMutationObservers · GitHub

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<!DOCTYPE html>
<html lang="en-us">
<head>
	<meta charset="utf-8" />
	<title>Why mutation observers are better than mutation events</title>
	<link rel="stylesheet" href="mutationobserver.css">
</head>
<body>
<header>
	<h1>Why mutation observers are better than mutation events</h1>
	<nav><a href="http://dev.opera.com/articles/view/mutation-observers-tutorial/">Return to article</a></nav>
</header>

<article>
	<p>In this example, we are creating 2500 paragraphs, and appending them to a document fragment. Then we'll append that document fragment to a <code>div</code> element. Rather than listen for <a href="mutationobserver-mutationevent.html">mutation events</a>, we'll use a mutation observer.</p>
	<p>Our mutation observer callback function was invoked <b class="numevents">0</b> time(s). </p>
	<p><button>Run demo</button></p>
</article>

<div id="demo"></div>

<script src="modemo.js"></script>
<script>
(function(d){
	eventcount = 0;
	var mocallback = function(mr){
		eventcount++;
		d.querySelector('.numevents').textContent = eventcount;
	},
	mo = new MutationObserver(mocallback),
	demo = d.querySelector('#demo');
	mo.observe(demo,{'childList':true});
})(document);
</script>

</body>
</html>