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:) :((
6,776 PointsI need help on this challenge
i don't understand why my code is not running , thanks.
var list = document.getElementsByTagName('ul')[0];
var p = document.getElementsByTagName('p');
list.addEventListener('click', function(e) {
if (e.target.tagName == 'BUTTON') {
let li = e.target.parentNode;
let prevP = p.previousElementSibling;
let ul = li.parentNode;
ul.insertBefore(li, 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>
2 Answers
Steven Parker
229,786 PointsWhoa ... you're going a bit overboard here. Here's a few hints:
- you won't need to define any additional globals
- you can navigate directly from the button (
e.target) to the paragraph - you won't need to reference the parent element
- you don't need to add any new elements
- but you do need to set the class on the paragraph
- this task can be done in one single statement
:) :((
6,776 Points"'js var list = document.getElementsByTagName('ul')[0];
var p = document.querySelector("p.highlight"); list.addEventListener('click', function(e) { if (e.target.tagName == 'BUTTON') { let li = e.target.parentNode; let prevP = p.previousElementSibling; let ul = li.parentNode; ul.insertBefore(li, prevP); } });"' "'html ><li><p class="highlight">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> "'
I tried putting a class to a paragraph , still doesn't work, i tried list.chidren and document.querySelector("list > p") but still the same
Steven Parker
229,786 PointsIt's hard to tell without formatting, but it looks like you went back to the original code — all of my original hints still apply to that code.
And the Markdown formatting marks for code are 3 accents (```), not 3 apostrophes (''').
:) :((
6,776 Points:) :((
6,776 PointsCan you please show an example, so i can understand better?
Steven Parker
229,786 PointsSteven Parker
229,786 PointsTry implementing the hints, then post your modified code if you're still having trouble.
And you might consider giving yourself a slightly more compact user name.
:) :((
6,776 Points:) :((
6,776 Points"' js var list = document.getElementsByTagName('ul')[0]; list.addEventListener('click', function(e) { if (e.target.tagName == 'BUTTON') { document.querySelector('p').className= "highlight";
} });"" i give up , i really can't understand and i did the whole chapter again and looked over mdn. :c
Steven Parker
229,786 PointsSteven Parker
229,786 PointsThe problem with "
document.querySelector('p')" is that it will always select the first paragraph on the page, which may not be the one which is a sibling of the pressed button. So it is important to use DOM traversal to find the correct paragraph.You had the right idea before to use "
previousElementSibling", it just needs to be employed in a different way.