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

Kevin Chan
Kevin Chan
3,818 Points
Posted by Kevin Chan
Kevin Chan
3,818 Points

Can't solve the challenge

Can someone teach me how to solve this challenge

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

for (let i = 0; i < list.length; i++) {
list[i].addEventListener('click', function(e) {
  if (e.target.tagName == 'BUTTON') {
    let para = e.target.previousElementSibling;
    let parent = para.parentNode;
    parent.className = 'highlight';
  }
});
}
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

Jacob Mishkin
Jacob Mishkin
23,118 Points
Jacob Mishkin
Jacob Mishkin
23,118 Points

You solved the hard part, but added some extra code. Remove the for loop you wrote, and then with the para var you created add the correct syntax to add the class highlight to the code as so: classList.add(); if you look at the HTML there is no need to get the parentNode as you are trying to select the p tag. Which is the previous element sibling.