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

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<!DOCTYPE html>
<html lang="en-us">
<head>
	<meta charset="utf-8" />
	<title>Observing the addition of child nodes</title>
	<link rel="stylesheet" href="mutationobserver.css">
</head>
<body>
<header>
	<h1>Observing the addition of child nodes</h1>
	<nav><a href="http://dev.opera.com/articles/view/mutation-observers-tutorial/">Return to article</a></nav>
</header>

<article>
	<p>In this example, clicking the <b>Add a node</b> button adds another paragraph element node to the document tree. Open the developer console to see what each mutation record reports.</p>
	<p><button>Add a node</button></p>
</article>

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

<script>
(function(d){
	var btn = d.querySelector('button'),
	demo = d.getElementById('demo'),
	clickhandler = function(){
		var p, sentence = 'Lorem ipsum dolar sit amet consecutum.';

		if( p !== undefined){
			p = p.cloneNode(true);
		} else {
			p = d.createElement('p');
			p.textContent = sentence;
		}
		demo.appendChild(p);
	}
	btn.addEventListener('click',clickhandler,false);

	var mocallback = function(mutationrecords){
		mutationrecords.map( function(mr){
			var mrtype = [];
			mrtype[0] = Object.prototype.toString.call(mr)+"\n";
			for( var o in mr ){
				mrtype.push( o +': '+mr[o] );
			}
			console.log( mrtype.join('\n') );
		});

	},
	mo = new MutationObserver(mocallback),
	demo = d.getElementById('demo');
	mo.observe(d.body,{'childList':true,'subtree':true});
})(document);
</script>

</body>
</html>