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

Mohamed Ali
Mohamed Ali
2,923 Points
Posted by Mohamed Ali
Mohamed Ali
2,923 Points

app.js

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.

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>
js/app.js 
let listItems;

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

Adam Pengh
Adam Pengh
29,881 Points
Adam Pengh
Adam Pengh
29,881 Points 
let listItems = document.querySelectorAll('ul#rainbow > li');
Adam Pengh
Adam Pengh
29,881 Points
Adam Pengh
Adam Pengh
29,881 Points

Sure, querySelectorAll will select all elements that match the query. The query itself is saying select all <li> elements that are direct children of a <ul> element with id="rainbow". You don't really need the ">" sign, it just makes it a little more specific. You could just use 

document.querySelectorAll('ul#rainbow li');

which would get you the same result.

Loy Yee Ko
Loy Yee Ko
5,814 Points
Loy Yee Ko
Loy Yee Ko
5,814 Points

Hi Adam Pengh could you explain why ('ul#rainbow > li') please? thanks!