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

I'm completely stuck and don't know where to start...

I don't have a good grasp on the items that were taught in this course, and have been stuck on this challenge for quite some time. Looked back at the previous videos and I'm barely able to understand what's going on.

var list = document.getElementsByTagName('ul')[0];
const highlight = document.getElementsByClassName('highlight');
const button = document.getElementsByTagName('button')[0];

list.addEventListener('click', function(e) {
  if (e.target.tagName == 'BUTTON') {
<!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 class="highlight">Element Selection</p><button>Highlight</button></li>
                <li><p class="highlight">Events</p><button>Highlight</button></li>
                <li><p class="highlight">Event Listening</p><button>Highlight</button></li>
                <li><p class="highlight">DOM Traversal</p><button>Highlight</button></li>
        <script src="app.js"></script>

1 Answer

Hey Brennen Bactista,

In your above code you have created a class attribute inside <p> elements and selected that element in js using a getElementById.

But in this challenge, you should dynamically insert class attribute to <p> elements using previousElementSibling property.

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

list.addEventListener('click', function(e) {
  if (e.target.tagName == 'BUTTON') {
    e.target.previousElementSibling.className = 'highlight';

In the above code, when the <button> is clicked it'll look for its immediate previous sibling which is <p> element and adds a class of highlight`.

Hope this helps!

Happy Coding!