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

Tim Frankie
Tim Frankie
7,181 Points
Posted by Tim Frankie
Tim Frankie
7,181 Points

I think there is more to this solution than I am putting. I thought all I should need it list.className = 'hightlight';

I don't really know where to go from here I thought I had it right but it says I am not selecting the proper element

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

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

Steven Parker
Steven Parker
229,644 Points
Steven Parker
Steven Parker
229,644 Points

A collection (like "list") does not have a "className" property.

Only individual elements have that property. But you wouldn't want to do that to the whole list anyway.

Let's take another look at the instructions: "When any one of the buttons is clicked, a class of highlight should be added to the paragraph element immediately preceding that button ...". So you'll want to use the current button (e.target) as a basis and then navigate to the paragraph element that occurs before it in the DOM. Add the class to that element.