Sandbox

Posted: **Thu Dec 20, 2007 10:40 pm**

Hi:

I'm a beginner with AJAX, just graduated, and I'm attempting to get my website to display rotating news items in a compact frame: essentially there are news items in a SQL database, and I am using setTimeout() to change the news item every 5 seconds [code below]:

This is an included .js file in the .html document (which is a "module" that uses Jumi).

Code: Select all


function switchNews(newsitem,loop){

xmlHttp=GetXmlHttpObject();

if (xmlHttp==null)
{
alert ("Unfortunately, your browser won't be able to view all of the information on our website. Please upgrade to IE5.5, Safari 1.1, FireFox, Opera 8.0, Netscape 7 or higher to be able to see our entire site! ");
return;
}
//This sets a global var "stopped" which will act as a "synchronizer". If loop and stopped are both true, the script
//doesn't make the query.
if(!loop){
stopped=true;
}

//This escapes out of the function if a user has clicked a link.
if(loop && stopped){
return;
}

lastitem = currentnews;
currentnews = newsitem;

var url="includes/jumies/gh_news.php";
url=url+"?newsitem="+newsitem;

xmlHttp.onreadystatechange=stateChanged;
xmlHttp.open("GET",url,true);
xmlHttp.send(null);

//This loops the news until the user has clicked a specific link.
if(!stopped){
if(currentnews == 5){
nextnews = 1;
}
else{
nextnews = currentnews + 1;
}
controller = setTimeout('switchNews(' + nextnews + ',1)',5000);
}
}

This works on all browsers except for IE7. On IE7, sometimes when I click another link on my website, Internet Explorer tells me that it cannot view the webpage, and displays an error, and clears the web browser viewing space. However-the website is displayed in the background before the error appears.

Which got me to thinking:

I believe what is happening in these circumstances is that I am clicking a link outside of the AJAX module while a xmlHTTPObject request was being handled by my PHP script- and then the PHP script fires off its reply, and "confuses" IE7.

I tried to remedy the problem by using clearTimeout(controller) in a function that was within the scope of controller, activated whenever the page was unloaded, but to no avail. For refrence, this was done in the tag of my template , ie:

Does anyone have any suggestions about how to remedy this or what might be going wrong?

Thanks very much in advance,
Stew

Sandbox

Using Ajax to display rotating news items in IE7, using Joomla/VirtueMart/sh404

Using Ajax to display rotating news items in IE7, using Joomla/VirtueMart/sh404