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

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<!DOCTYPE html>
<html lang="en-us">
<head>
	<meta charset="utf-8" />
	<title>Getting to Know Mutation Observers: The problem with mutation events</title>
	<link rel="stylesheet" href="mutationobserver.css">
</head>
<body>
<header>
	<h1>The problem with 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. Each element added fires a new <code>DOMNodeInserted</code> event, which causes our event handler to be invoked.</p>

	<p>Our <code>DOMNodeInserted</code> event handler was invoked <b class="numevents">0</b> times.</p>
	<p><button>Run demo</button></p>
</article>

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

<script src="modemo.js"></script>
<script>
(function(d){
	var demo = d.getElementById('demo');
	eventcount = 0;
	onnodeinsert = function(){
		eventcount++;
		var numevents = d.querySelector('.numevents');
		numevents.textContent = eventcount;
	}
	demo.addEventListener('DOMNodeInserted',onnodeinsert,false);
})(document);
</script>

</body>
</html>