function doxhr(url){
	if(!document.getElementById || !document.createTextNode){return;}		
	var request;
	try{
		request = new XMLHttpRequest();
	}catch(error){
		try{
			request = new ActiveXObject("Microsoft.XMLHTTP");
		}catch(error){
			//document.getElementById("activityContent").innerHTML = "Please upgrade your browser";
			return;
		}
	}
		
	request.open('get',url,true);
	request.onreadystatechange=function(){			
		if(request.readyState == 4){
			if (request.status && /200|304/.test(request.status))
			{
				retrieved(request);
			} else{
				failed(request);
			}
		}
	}
	request.setRequestHeader('If-Modified-Since','Wed, 05 Apr 2006 00:00:00 GMT');
	request.send(null);		
}

function retrieved(requester) {		
	var data=requester.responseXML;

	var activity1 = data.getElementsByTagName("snippet_1");

	actRand1 = Math.ceil(activity1.length*Math.random()-1);

	activitiesCount1 = activity1.length - 1;

	for(var i = 0; i < activity1.length; i++) {
		activities1[i] = activity1[i].firstChild.nodeValue;
    	}

	obj1 = document.getElementById("activityContent_1");

	var text1='';

	text1 += '<p>' + activities1[actRand1] + '</p>';

	obj1.innerHTML = text1;
	
	activitiesLink1 = actRand1;
		
}
function failed(requester){
	//alert('The XMLHttpRequest failed. Status: '+requester.status);  	
}

var activities1 = new Array();
var activitiesCount1;
var actRand1, actRand2; 

// Set initial variables

var activitiesLink1;

function getNextHeadline(num) {
	var text='';
	if (num==1) {
		++activitiesLink1;
		if (activitiesLink1 > activitiesCount1) activitiesLink1 = 0;
		obj = document.getElementById("activityContent_"+num);

		text += '<p>' + activities1[activitiesLink1] + '</p>';

		obj.innerHTML = text;
	}
}

function getPrevHeadline(num) {
	var text='';
	if (num==1) {
		--activitiesLink1;
		if (activitiesLink1 < 0) activitiesLink1 = activitiesCount1;
		obj = document.getElementById("activityContent_"+num);

		text += '<p>' + activities1[activitiesLink1] + '</p>';
		obj.innerHTML = text;
	}
}

function init() {
	doxhr("/literacy_centers_photos/xml_snippets/activities.xml");
}
//addLoadEvent(init);