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

:) :((
:) :((
6,776 Points
Posted by :) :((
:) :((
6,776 Points

I can't understand the code can someone explain?

I do not understand why the code is not working , can someone explain the for loop part?

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

for(let 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

KRIS NIKOLAISEN
KRIS NIKOLAISEN
54,971 Points

I pasted your code into the challenge and it passed. Although the instructions specified you are to select list items within the ul with id = rainbow. You can do this with the following:

const listItems= document.querySelectorAll("#rainbow li");

For the given html it doesn't matter since there is only one ul and the number of list items equals the number of colors. But if you had two uls like this for example:

<!DOCTYPE html>
<html>
  <head>
    <title>Rainbow!</title>
  </head>
  <body>

    <ul>
      <li>one</li>
      <li>two</li>
      <li>three</li>
    </ul>


    <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="app.js"></script>
  </body>
</html>

all the list items would be selected and colors would be assigned starting at 

<li>one</li>

and ending with

<li>This should be green</li>

The loop assigns colors to list items based on index. The list item with index 0 will be assigned the color from the colors array with index 0 and so on.

:) :((
:) :((
6,776 Points
:) :((
:) :((
6,776 Points

Thanks, i got a little stuck