Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

JavaScript JavaScript and the DOM (Retiring) Getting a Handle on the DOM Selecting Multiple Elements

Posted by Tim Brooks
Tim Brooks
2,339 Points

DOM: Can't get list items to turn to rainbow colors

Hi, I'm stuck on getting this code to turn the quiz example to rainbow colors:

var listItems; var colors = ["#C2272D", "#F8931F", "#FFFF01", "#009245", "#0193D9", "#0C04ED", "#612F90"];

for(var i = 0; i < colors.length; i ++) { listItems[i].style.color = getElementByID("rainbow").colors(i);
}

js/app.js 
var listItems;
var colors = ["#C2272D", "#F8931F", "#FFFF01", "#009245", "#0193D9", "#0C04ED", "#612F90"];

for(var i = 0; i < colors.length; i ++) {
 listItems[i].style.color = getElementByID("rainbow").colors(i);     
}
index.html 
<!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>

3 Answers

Rabin Gharti Magar
seal-mask
PLUS
.a{fill-rule:evenodd;}techdegree seal-36
Rabin Gharti Magar
Front End Web Development Techdegree Graduate 20,937 Points
Rabin Gharti Magar
.a{fill-rule:evenodd;}techdegree seal-36
Rabin Gharti Magar
Front End Web Development Techdegree Graduate 20,937 Points

Hey Tim Brooks,

First, you need to select <ul> element with the id of rainbow and use the parentNode.children property.

It should look like this:

var listItems = document.querySelector('#rainbow').children;
var colors = ["#C2272D", "#F8931F", "#FFFF01", "#009245", "#0193D9", "#0C04ED", "#612F90"];

for(var i = 0; i < colors.length; i ++) {
  listItems[i].style.color = colors[i];    
}

To learn about this property, check out this website: https://developer.mozilla.org/en-US/docs/Web/API/ParentNode/children#Syntax

Hope this helps!

Happy Coding!

Tim Brooks
Tim Brooks
2,339 Points
Tim Brooks
Tim Brooks
2,339 Points

Thanks, that worked! I'm still puzzling over it bit, but hopefully this stuff will sink in.

Rabin Gharti Magar
seal-mask
PLUS
.a{fill-rule:evenodd;}techdegree seal-36
Rabin Gharti Magar
Front End Web Development Techdegree Graduate 20,937 Points
Rabin Gharti Magar
.a{fill-rule:evenodd;}techdegree seal-36
Rabin Gharti Magar
Front End Web Development Techdegree Graduate 20,937 Points

I will break this down into small sections so you can have a better understanding: 

<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>
  1. Inside <ul> there are 7 <li> tags.
  2. <li> is the children of <ul> tag.
  3. <ul> has the id of #rainbow.
var listItems = document.querySelector('#rainbow').children;
var colors = ["#C2272D", "#F8931F", "#FFFF01", "#009245", "#0193D9", "#0C04ED", "#612F90"];

for(var i = 0; i < colors.length; i ++) {
  listItems[i].style.color = colors[i];    
}

  1. Here in JS, I have selected <ul> tag with its id using a querySelector method and I used a children property, this property returns a collection of an element's child elements. In this case, it'll return <ul> child elements <li>. I then stored it in a variable named listItems.

  2. Secondly, I created an array variable named colors and stored 7 different colors which I will apply in <li> tags stored inside <ul>.

  3. And finally, I used a for loops to iterate through each <li> tags and apply the color to each of them. A for loop repeats until a specified condition evaluates to false.

Hope this helps!

Happy Coding!