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

Anthony Manriquez
Anthony Manriquez
2,917 Points
Posted by Anthony Manriquez
Anthony Manriquez
2,917 Points

Selecting collections challenge

I continue to get "There was an error with your code: TypeError: 'null' is not an object (evaluating 'listItems[i]')" when trying to set my variable listItems to satisfy the challenge. Maybe I'm going about selecting the ID incorrectly? I've tried all of the selectors we went over beforehand and all have returned similar errors, wondering if anyone could provide some insight.

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

for(var i = 0; i < colors.length; i ++) {
  listItems[i].style.color = 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>
Elias K. Salem
Elias K. Salem
22,283 Points

I think you need to select the name of the id so: var listItems = document.getElementById('rainbow'); might work.

1 Answer

Tomasz Grodzki
Tomasz Grodzki
8,130 Points
Tomasz Grodzki
Tomasz Grodzki
8,130 Points

Firstly, you're using getElementById, so you have to use Id, not a tag. But even if you will use a proper tag this won't work. listItem should refer to collection.