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

Italo Oliveira
Italo Oliveira
4,289 Points
Posted by Italo Oliveira
Italo Oliveira
4,289 Points

My code doesn't trigger the challenge but I think it's correct

It says one or more buttons doesn't affect the related paragraph of itself when it all buttons actually affect each paragraph

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

list.addEventListener('click', function(e) {
  if (e.target.tagName == 'BUTTON') {
    let prevSib = e.target.previousElementSibling;
    let innerHTML = prevSib.innerHTML;
    prevSib.innerHTML = '<mark>' + innerHTML + '</mark>';
  }
});
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

martinjones1
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
martinjones1
Front End Web Development Techdegree Graduate 44,819 Points
martinjones1
.a{fill-rule:evenodd;}techdegree seal-36
martinjones1
Front End Web Development Techdegree Graduate 44,819 Points

You are actually very close, just need to double check the task at hand. It just wants you to add the class name of "highlight" to the previous P element, no need to add innerHTML.

For example:

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

list.addEventListener('click', function(e) {
  if (e.target.tagName == 'BUTTON') {
    let prevSib = e.target.previousElementSibling;
    prevSib.className = "highlight";
  }
});