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

Kevin Horwitz
Kevin Horwitz
Full Stack JavaScript Techdegree Student 3,076 Points

Sibling Traversal quiz

I feel live I've done everything correctly. My code is even working in the preview window, but the quiz keeps telling me otherwise

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

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

2 Answers

Robert Manolis
Robert Manolis
Treehouse Guest Teacher

Hi Kevin, it looks like this is the problem. You can't say p.classList = 'highlight';. ClassList is a collection containing all the classNames. So you could say p.classList.add('highlight');, or probably, p.className = 'highlight';,

Hope that helps. :)