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 Getting a Handle on the DOM Select by Tag Name

Posted by Aikins Dwamena
Aikins Dwamena
4,423 Points

Bummer: Cannot read property '1' of null How do i fix this?

Code runs but i get this error after

app.js 
// Complete the challenge by writing JavaScript below
const colors = ["#C2272D", "#F8931F", "#FFFF01", "#009245", "#0193D9", "#0C04ED", "#612F90"];
let listItems = document.getElementsByTagName('ul');

for ( let i = 0; i < colors.length; i++ ) {
  listItems[i].style.color = colors[i];    
}
index.html 
<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="utf-8">
    <title>JavaScript and the DOM</title>
  </head>
  <body>
    <h1>My List</h1>
    <ul>
      <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="app.js"></script>
  </body>
</html>

1 Answer

Steven Parker
Steven Parker
231,248 Points
Steven Parker
Steven Parker
231,248 Points

The instructions say "The collection should contain all list items", so you'll need to select the list items (li) instead of the list itself (ul).

2pd
2pd
8,123 Points

Thanks, Steven. Can you (or someone else) explain what "Bummer: Cannot read property '1' of null" means in this context?

Steven Parker
Steven Parker
231,248 Points
Steven Parker
Steven Parker
231,248 Points

It must have something to do with how the challenge evaluates your code internally. Outside of the challenge, I would expect to see a different error message.