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

Flor M Nazari
Flor M Nazari
4,939 Points
Posted by Flor M Nazari
Flor M Nazari
4,939 Points

Hi, I couldn't solve this and would appreciate your explanation along with the solution to this challenge. Thanks

I cant determine when to use getElementByID and when to use querySelector ?

js/app.js 
let navigationLinks = document.querySelectorAll("nav li a");
let galleryLinks = document.querySelectorAll(ul id="gallery");
let footerImages;
index.html 
<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
    <title>Nick Pettit | Designer</title>
    <link rel="stylesheet" href="css/normalize.css">
    <link href='http://fonts.googleapis.com/css?family=Changa+One|Open+Sans:400italic,700italic,400,700,800' rel='stylesheet' type='text/css'>
    <link rel="stylesheet" href="css/main.css">
    <link rel="stylesheet" href="css/responsive.css">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
  </head>
  <body>
    <header>
      <a href="index.html" id="logo">
        <h1>Nick Pettit</h1>
        <h2>Designer</h2>
      </a>
      <nav>
        <ul>
          <li><a href="index.html" class="selected">Portfolio</a></li>
          <li><a href="about.html">About</a></li>
          <li><a href="contact.html">Contact</a></li>
        </ul>
      </nav>
    </header>
    <div id="wrapper">
      <section>
        <ul id="gallery">
          <li>
            <a href="img/numbers-01.jpg">
              <img src="img/numbers-01.jpg" alt="">
              <p>Experimentation with color and texture.</p>
            </a>
          </li>
          <li>
            <a href="img/numbers-02.jpg">
              <img src="img/numbers-02.jpg" alt="">
              <p>Playing with blending modes in Photoshop.</p>
            </a>
          </li>
        </ul>
      </section>
      <footer>
        <a href="http://twitter.com/nickrp"><img src="img/twitter-wrap.png" alt="Twitter Logo" class="social-icon"></a>
        <a href="http://facebook.com/nickpettit"><img src="img/facebook-wrap.png" alt="Facebook Logo" class="social-icon"></a>
        <p>&copy; 2016 Nick Pettit.</p>
      </footer>
    </div>
  <script src="js/app.js"></script>
  </body>
</html>
Nehemie Balukidi
Nehemie Balukidi
405 Points
Nehemie Balukidi
Nehemie Balukidi
405 Points

what are you trying to accomplish or what is the challenge about?

1 Answer

Steven Parker
Steven Parker
229,786 Points
Steven Parker
Steven Parker
229,786 Points

The argument to querySelectorAll should be a CSS-style selector, like you made for task 1. There won't be anything outside of the quotes.

A selector that refers to an ID will have a "#" symbol in front of the name. And links are implemented with anchor ("a") elements, as you correctly indicated for the task 1 selector.

Also, for descendant selectors, it's generally only necessary to mention the outer container and the final target, so for task 1 just "nav a" would do.