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Iulia Suviteanu
822 PointsHi. I don't know the answer fot this topic. Can you help me, please?
I don't understand why this is not working.
const list = document.getElementsByTagName('ul')[0];
const button = document.getElementsByTagName('button');
list.addEventListener('click', function(e) {
if (e.target.tagName == 'BUTTON') {
let li = event.target.parentNode;
let prevP = button.previousElementSibling;
if (prevP) {
li.insertBefore(button, prevP);
}
}
});
<!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>
3 Answers
Iulia Suviteanu
822 Pointsconst list = document.getElementsByTagName('ul')[0]; const button = document.getElementsByTagName('button'); list.addEventListener('click', function(e) { if (e.target.tagName == 'BUTTON') { let prg = event.target.previousElementSibling; if (prg) { prg.addClass = 'highlight'; } } });
I tried this...but it's not working
KRIS NIKOLAISEN
54,971 PointsaddClass is a JQuery method which we aren't using here but would be:
prg.addClass('highlight')
instead of:
prg.addClass = 'highlight'
Since we aren't using JQuery try
prg.className = 'highlight'
Krystal Smith-Moore
4,881 PointsThink of the button's previous sibling and add the style there using previousSiblingElement().
Iulia Suviteanu
822 PointsIulia Suviteanu
822 Pointsthis is the problem: A delegated click event listener has been attached to the selected ul element, which is stored in the variable list. The handler is targeting each button in the list. When any one of the buttons is clicked, a class of highlight should be added to the paragraph element immediately preceding that button inside the parent list item element. Add the code to create this behavior on line 5.