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Start your free trialDaniel Statsenko
Full Stack JavaScript Techdegree Student 4,235 PointsOne or more of the buttons do not affect their previous sibling paragraphs.
My code highlights the <p> element of the previous list item, however I keep getting the "One or more of the buttons do not affect their previous sibling paragraphs." error message.
var list = document.getElementsByTagName('ul')[0];
list.addEventListener('click', function(e) {
if (e.target.tagName == 'BUTTON') {
let li = e.target.parentNode;
let prevLi = li.previousElementSibling;
if (prevLi) {
let p = prevLi.firstElementChild;
p.className = 'highlight';
}
}
});
var list = document.getElementsByTagName('ul')[0];
list.addEventListener('click', function(e) {
if (e.target.tagName == 'BUTTON') {
let li = e.target.parentNode;
let prevLi = li.previousElementSibling;
if (prevLi) {
let p = prevLi.firstElementChild;
p.className = 'highlight';
}
}
});
<!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>
Mod edit: Fixed code markdown -- triple backticks need to be on their own line before and after code.
1 Answer
Rabin Gharti Magar
Front End Web Development Techdegree Graduate 20,928 PointsHey Daniel Statsenko,
For this challenge, you don't have to create any new variables. You simply use a previousElementSibling
and add a class name.
Here's the final version:
var list = document.getElementsByTagName('ul')[0];
list.addEventListener('click', function(e) {
if (e.target.tagName == 'BUTTON') {
e.target.previousElementSibling.classList.add('highlight');
}
});
There are three things happening on the above code:
- Inside the parentheses of conditional statement
e.target.tagName
looks specifically for abutton tag
. - Inside the code block if it matches, you simply use
e.target
along withpreviousElementSibling
method which will look forbutton
previous sibling which is<p> tag
. - Finally add the class name of
highlight
to<p> tags
To learn how event target
works, check out this link: https://developer.mozilla.org/en-US/docs/Web/API/Event/target
Hope this helps!
Daniel Statsenko
Full Stack JavaScript Techdegree Student 4,235 PointsDaniel Statsenko
Full Stack JavaScript Techdegree Student 4,235 PointsThank you for your help Rabin :)