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

Niki kalwar
Niki kalwar
1,892 Points
Posted by Niki kalwar
Niki kalwar
1,892 Points

TypeError: 'undefined' is not a function (evaluating 'galleryLinks.querySelectorAll("a")')

I am not able to select the unordered list for galleryLinks var can you please advise.

js/app.js 
let navigationLinks=document.querySelectorAll("nav li a");
let galleryLinks=document.querySelectorAll(".gallery ul " );
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>

1 Answer

Carlos Chavez
Carlos Chavez
5,691 Points
Carlos Chavez
Carlos Chavez
5,691 Points

The only issue I can see is that you mixed class with id.

In your html code you have 

    <div id="wrapper">
      <section>
        <ul id="gallery"> <!-- here-->
          <li>
            <a href="img/numbers-01.jpg">
              <img src="img/numbers-01.jpg" alt="">
              <p>Experimentation with color and texture.</p>
            </a>
          </li>
            . 
            .
            . etc

    </div>

When selecting your element, use '#gallery', not '.gallery', because it's and id and not a class. Also, the element with id = gallery is the ul, so it feels redundant to use "#gallery ul". "#gallery" would be enough

Niki kalwar
Niki kalwar
1,892 Points
Niki kalwar
Niki kalwar
1,892 Points

Thanks will check . :)