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

Yuichi Narisawa
Yuichi Narisawa
19,548 Points
Posted by Yuichi Narisawa
Yuichi Narisawa
19,548 Points

I get totally lost of this code challenge...

I finished this corse except this challenge. I would appreciate any advise / hint!

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

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

  }
});
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

Steven Parker
Steven Parker
231,271 Points
Steven Parker
Steven Parker
231,271 Points

:point_right: The task is to add the class to the paragraph before the button.

So you want to select the paragraph element which you know is immediately previous to the button itself. Since the provided code already filters out only events on buttons, you can get the previousElementSibling of the event target to get the paragraph, and then use that to set the class name.

Yuichi Narisawa
Yuichi Narisawa
19,548 Points
Yuichi Narisawa
Yuichi Narisawa
19,548 Points

Hi Steven, Thank you for your advice! I'd finally completed the course!