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JavaScript Interactive Web Pages with JavaScript Traversing and Manipulating the DOM with JavaScript Traversing Elements

Posted by Alexander Davison
Alexander Davison
65,469 Points

Someone help please!

It says: "There was an error with your code: TypeError: 'undefined' is not a function (evaluating 'navigation.children.querySelector("a")')" and I cannot find the bug! Please help

app.js 
//Select the naviagation
var navigation = document.getElementById("navigation");

//Select all listItems from the navigation
var listItems = navigation.children.querySelector("a");

//When a navigation link is pressed
var linkListener = function() {
  console.log("Listener is clicked!");
}

var bindEventsToLinks = function(listItem) {
  //Select the anchor
  var anchor = listItem;
  //Bind the linkListener to the anchor element (a) 
  anchor.onclick = linkListener;
}

for(var i = 0; i < listItems.length ; i++) {
    bindEventsToLinks(listItems[i]);
}
index.html 
<!DOCTYPE html>
<html>
<head></head>
<body>

<ul id="navigation">
  <li>
    <a href="#home">Home</a>
  </li>
  <li>
    <a href="#about">About</a>
  </li>
  <li>    
    <a href="#contact">Contact</a>
  </li>
</ul>

<p>A few of my favourite things:</p>
<ul>
  <li>
    Rain drops on roses
  </li>
  <li>
    Whiskers on kittens
  </li>
  <li>
    Brown paper packages wrapped up with string
  </li>
</ul>

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

1 Answer

Jennifer Nordell
seal-mask
STAFF
.a{fill-rule:evenodd;}techdegree
Jennifer Nordell
Treehouse Teacher
Jennifer Nordell
.a{fill-rule:evenodd;}techdegree
Jennifer Nordell
Treehouse Teacher

You clearly did well on the first step! But you missed the line in the instructions where it says to put the query selector on line 14. So line 5 should be:

var listItems = navigation.children;

And line 14 should be:

var anchor = listItem.querySelector("a");

Happy coding!

Alexander Davison
Alexander Davison
65,469 Points

Thank you so much!