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

andres ponton
andres ponton
10,350 Points
Posted by andres ponton
andres ponton
10,350 Points

I dont know how to solve this challenge

I dont understant how to approach this, what is the highlight property, this is what i have so far

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

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

  }
});
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
231,271 Points
Steven Parker
Steven Parker
231,271 Points

There's no "highlight" property, what the challenge wants you to do is "to add a class of highlight". So "highlight" is just a literal class name.

Also, the paragraph is a peer element to the button, so you won't need to access a parent element to get to it.

Update: Your second try is close, but the paragraph they want you to change is the sibling of the button ("e.target") instead of the one that is a sibling of the "list".

andres ponton
andres ponton
10,350 Points
andres ponton
andres ponton
10,350 Points

thanks for your response, this is what ive got, but it doesnot work

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

list.addEventListener('click', function(e){ if (e.target.tagName == 'BUTTON') { var p=list.previousElementSibling; p.className='highlight';

} });