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

Nazeim Brame
Nazeim Brame
6,544 Points
Posted by Nazeim Brame
Nazeim Brame
6,544 Points

Not sure how to answer this one

Confused on how to set this up properly.

js/app.js 
var listItems = document.getElementById('rainbow');

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

1 Answer

Harald N
Harald N
15,843 Points
Harald N
Harald N
15,843 Points

Was a bit tricky to get the problems.

  1. document.getElementById('rainbow'); gets only the UL element, and by using a querySelectorAll('#rainbow li') you target all the li elements inside rainbow.
  2. Because you run the loop before declaring the color array, the loop is trying to access an (at time of running) non existing array of colors.

Added the code that worked for me, hope this helps, if so please mark this question as answered.

//using the querySelectorAll here instead, targets all the li inside #rainbow ul.
var listItems = document.querySelectorAll('#rainbow li');
//Moved the array of color, so it is declared before the loop.
var colors = ["#C2272D", "#F8931F", "#FFFF01", "#009245", "#0193D9", "#0C04ED", "#612F90"];
//Run the loop.
for (let i = 0; i < listItems.length; i++) {
    listItems[i].style.color = colors[i];
}