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

Igor Pavlenko
Igor Pavlenko
12,925 Points
Posted by Igor Pavlenko
Igor Pavlenko
12,925 Points

stuck on the practice code

hello guys i have a problem with the below, i feel like my logic is wrong?

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

list.addEventListener('click', function(e) { if (e.target.tagName == 'BUTTON') { let p = list.children; /* here i will declare the children elements of ul / p.className = 'highlight'; / change the class name to the required ? */ } });

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

list.addEventListener('click', function(e) {
  if (e.target.tagName == 'BUTTON') {
    let p = list.children;
    p.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>
Justin Roberts
Justin Roberts
14,583 Points
Justin Roberts
Justin Roberts
14,583 Points

Hi Igor, what exactly is the problem you're having?

It seems like one problem you might be having is that you're setting the class of all the li tags to highlight. If you're wanting to just change the one that was clicked you would have to utilize the event. I think it would be something like "let p = e.target.className = 'highlight';".

But that would be for the button. So if you wanted to highlight the li I think you would want something like this:

let p = e.target.parentElement.className = 'highlight';

1 Answer

Vic Mercier
Vic Mercier
3,276 Points
Vic Mercier
Vic Mercier
3,276 Points

Hi Igor , I think you will have to use the previousElementSibling method because now the parent of the button and the p are the li element.