Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

JavaScript AJAX Basics (retiring) Programming AJAX Create a callback

Rafael Sanchez
Rafael Sanchez
11,804 Points
Posted by Rafael Sanchez
Rafael Sanchez
11,804 Points

need help with this challenge please.

I can't seem to find the problem here.

app.js 
var xhr = new XMLHttpRequest();
xhr.onreadystatechange function() {
xhr.open('GET', 'sidebar.html');
xhr.send();
};
index.html 
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>AJAX with JavaScript</title>
  <script src="app.js"></script>
</head>
<body>
  <div id="main">
    <h1>AJAX!</h1>
  </div>
  <div id="sidebar"></div>
</body>
</html>

1 Answer

Sam Wilskey
Sam Wilskey
3,420 Points
Sam Wilskey
Sam Wilskey
3,420 Points

Hello Rafael Sanchez,

The question for this problem is to create an empty anonymous function to the onreadystatechange event handler. Your code is very close but just a couple of small errors.

First to add the anonymous function to the handler you need to add a assignment operator between the onreadystatechange and the function deceleration.

Second since the Challenge is asking for a empty function you do not want to wrap the brackets around any code.

var xhr = new XMLHttpRequest();
xhr.onreadystatechange = function() {
}
xhr.open('GET', 'sidebar.html');
xhr.send();

Hope this helps!