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

charlie alton
charlie alton
Front End Web Development Techdegree Student 8,879 Points

I cant figure this out.

I dont remember them teaching me this in this course. I need help?

var list = document.getElementsByTagName('ul')[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>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>
Karla Walker
.a{fill-rule:evenodd;}techdegree seal-36
Karla Walker
Full Stack JavaScript Techdegree Graduate 15,865 Points

Hi charlie alton ! So the code challenge is asking you to add a class to the <p> tag, which is the previous sibling of the button you are clicking. The <button> element you are clicking and need to reference is equal to e.target. The challenge shares a link to the previousElementSibling property that you can use to get the <p> tag, I shared the link below:


Once you have the <p> tag saved, you can use classList.add() to add the 'highlight' class to the <p> tag.

Here's a ink to the classList documentation in case you need a refresher on that:


I hope this helps! :)

1 Answer

  1. Use the previousElementSibling property for e.target to select the <p> element that's beside each <button> element.
  2. Use the className property to set the classes of the selected <p> elements to highlight.