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geehun seng
1,705 PointsHelp me to find the mistake in this code below please
We have some JavaScript code that will cycle over list items and apply colors from an array called colors. The code will apply the first color to the first list item, the second color to the second list item and so on. But the code is not complete. On line 1 of app.js, set the variable listItems to refer to a collection. The collection should contain all list items in the unordered list element with the id of rainbow.
<!DOCTYPE html>
<html>
<head>
<title>Rainbow!</title>
</head>
<body>
<ul id="rainbow">
<li>This should be red</li>
<li>This should be orange</li>
<li>This should be yellow</li>
<li>This should be green</li>
<li>This should be blue</li>
<li>This should be indigo</li>
<li>This should be violet</li>
</ul>
<script src="js/app.js"></script>
</body>
</html>
let listItems = document.querySelector("#rainbow");
const colors = ["#C2272D", "#F8931F", "#FFFF01", "#009245", "#0193D9", "#0C04ED", "#612F90"];
for(var i = 0; i < colors.length; i ++) {
listItems[i].style.color = colors[i];
}
3 Answers
Robert Stewart
11,921 PointsThe answer is simple, you are trying to use the #rainbow item like an array but it's an html element. You need to query the child elements so you can loop through them.
Change: let listItems = document.querySelector("#rainbow");
to: let listItems = document.querySelector("#rainbow").children;
and everything should work.
P.S. Not all browsers support the ES6 syntax yet so be careful using let and const.
Seth Kroger
56,413 Pointsdocument.querySelector() will only return one element, not a collection, so there's no way to array indexes on it without an error. (also the fact that you're selecting an id is another indication you'll only get one, not many) This element is the entire list, but you want each list item to change the color so you'll need select the list items inside it.
geehun seng
1,705 Pointsthank you so much guys.