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JavaScript JavaScript and the DOM (Retiring) Traversing the DOM Sibling Traversal

Posted by Colin Bondi
Colin Bondi
8,005 Points

Can't figure this out, it works in the browser but not for this challenge.

I don't know what I'm doing wrong here, I've tired this in the browser and it adds the correct class to the correct element but it won't take my answer...

app.js 
var list = document.getElementsByTagName('ul')[0];

list.addEventListener('click', function(e) {
  if (e.target.tagName == 'BUTTON') {
   let prevElement = list.previousElementSibling;
   prevElement.className = "hightlight";
  }
});
index.html 
<!DOCTYPE html>
<html>
    <head>
        <title>JavaScript and the DOM</title>
    </head>
    <link rel="stylesheet" href="style.css" />
    <body>
        <section>
            <h1>Making a Webpage Interactive</h1>
            <p>Things to Learn</p>
            <ul>
                <li><p>Element Selection</p><button>Highlight</button></li>
                <li><p>Events</p><button>Highlight</button></li>
                <li><p>Event Listening</p><button>Highlight</button></li>
                <li><p>DOM Traversal</p><button>Highlight</button></li>
            </ul>
        </section>
        <script src="app.js"></script>
    </body>
</html>

1 Answer

Rohald van Merode
seal-mask
STAFF
.a{fill-rule:evenodd;}techdegree seal-36
Rohald van Merode
Treehouse Staff
Rohald van Merode
.a{fill-rule:evenodd;}techdegree seal-36
Rohald van Merode
Treehouse Staff

Hey Colin,

Currently you're selecting the previousElementSibling of the list element. The challenge however asks to select the sibling of the clicked button so you'll want to check what element got clicked using e.target.

After adjusting that there's also a typo in the className where it says hightlight instead of highlight

Hope this helps 🙂

Colin Bondi
Colin Bondi
8,005 Points

Thanks that cleared it up for me!