function treeHandler(id) {
	this.id = id;
	this.tmpHTML = '';
	document.write('<style type="text/css">');
	document.write('#'+ id +' { position: relative; display: none; visibility: hidden; }');
	document.write('</style>');
}

treeHandler.prototype.expand = function() {
	if(clientEnvironment.isW3C) {
		var tgt = document.getElementById(this.id);
		var display = snippets.getCSSProp(tgt, 'display');
		var visibility = snippets.getCSSProp(tgt, 'visibility');
		if(display == 'block') {
			tgt.style.visibility = 'hidden';
			tgt.style.display = 'none';
		} else {
			tgt.style.visibility = 'visible';
			tgt.style.display = 'block';
		}
	}
}