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

Aziz Kemal HOSCAN
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Aziz Kemal HOSCAN
Full Stack JavaScript Techdegree Graduate 16,113 Points

Anyone solved this? I do not see what is missing in my solution?

n

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

list.addEventListener('click', function(e) {
  if (e.target.tagName == 'BUTTON') {
    let p = e.target.parentNode;
    let prevli = p.previousElementSibling;
    prevli.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

Armin Kadic
Armin Kadic
16,242 Points

There is no need for declaring the "p" and "prevli" variable. It asks you to add a class of "highlight" to the <p> element that's an immediate PREVIOUS SIBLING of the button BEING clicked. So you have to target the previous sibling of the button clicked. You can do that by typing e.target.previousElementSibling and then you just continue on the same line to change the .className to = "highlight". I hope I didn't confuse you even more :)