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

Paul Walker
Paul Walker
28,904 Points
Posted by Paul Walker
Paul Walker
28,904 Points

A delegated click event listener has been attached to the selected ul element, which is stored in the variable list. The

Not sure where to go from here. Thanks.

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

list.addEventListener('click', function(e) {
  if (e.target.tagName == 'BUTTON') {
     let list = event.target.parentNode;
      p.insertBefore('.hightlight');
  }
});
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>

2 Answers

Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

Remember you're just adding a class.

For this challenge, you do not need to insert a new element into the DOM. You only need to identify the existing paragraph element and add a class to it. Either the className property or the classList.add() method might be useful here.

You also won't need to traverse back to the parent of the button, since the paragraph you want to change is the element right before the button. The property previousElementSibing might be useful here.

Paul Walker
Paul Walker
28,904 Points
Paul Walker
Paul Walker
28,904 Points

Got it. I accidentally typed the answer. Thanks.

Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

Accidentally typed both the right property to select the correct element and the right method to set the class?

Now that was pretty darn lucky. I'd suggest you run get a lottery ticket. :laughing: