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JavaScript JavaScript and the DOM (Retiring) Traversing the DOM Child Traversal

Isaac Hughes
Isaac Hughes
3,711 Points
Posted by Isaac Hughes
Isaac Hughes
3,711 Points

Cant seem to figure out children background color

The error i get is that it is undefined but I cannot figure out why it does that

app.js 
const section = document.querySelector('section');
let paragraphs=section.children;

for(let i=0; i< paragraphs.length; i+=1){
    paragraphs.style.backgroundColor='blue';
}
index.html 
<!DOCTYPE html>
<html>
    <head>
        <title>Child Traversal</title>
    </head>
    <body>
        <section>
            <p>This is the first paragraph</p>
            <p>This is a slightly longer, second paragraph</p>
            <p>Shorter, last paragraph</p>
        </section>
        <footer>
            <p>&copy; 2016</p> 
        </footer>
        <script src="app.js"></script>
    </body>
</html>
Cheo R
Cheo R
37,150 Points
Cheo R
Cheo R
37,150 Points 
paragraphs.style.backgroundColor='blue';

You're close. Two things to look at:

  • paragraphs: needs to be indexed
  • backgroundColor: if you look at the preview, it shows p's background as blue, but the prompt asks to turn the paragraph text blue.
Isaac Hughes
Isaac Hughes
3,711 Points
Isaac Hughes
Isaac Hughes
3,711 Points

my problem though is trying to index it I looked back at the videos but cant seem to find it

1 Answer

Nick Rocha
Nick Rocha
7,876 Points

don't forget that index or i is a variable (let i = 0) just like your paragraphs variable

the index allows you to use or move the same code across the paragraphs variable like an array [p, p, p]

it should look something like: paragraphs [].style.....

Isaac Hughes
Isaac Hughes
3,711 Points
Isaac Hughes
Isaac Hughes
3,711 Points

I think the main issue I was having was that I was using backgroundColor instead of .color it let me pass then it mentioned something about index but I can't remember what it was, I seriously feel like smacking my forehead on the desk sometimes gahh XD