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

Raeed Sabree
Raeed Sabree
10,664 Points
Posted by Raeed Sabree
Raeed Sabree
10,664 Points

On line 14 of the app.js, we want to get the anchor (the a element) from inside the listItem. Use a method to traverse a

On line 14 of the app.js, we want to get the anchor (the a element) from inside the listItem. Use a method to traverse and select the anchor.

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

//Select all listItems from the navigation
var listItems = navigation.children;

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

var bindEventsToLinks = function(listItem) {
  //Select the anchor
  var anchor = listItem.onClick("a");
  //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>

2 Answers

Mark Wilkowske
PLUS
Mark Wilkowske
Courses Plus Student 18,131 Points
Mark Wilkowske
Mark Wilkowske
Courses Plus Student 18,131 Points

Try this:

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

.querySelector() returns the first element you specify that is a descendant of the element you call it on.

Raeed Sabree
Raeed Sabree
10,664 Points
Raeed Sabree
Raeed Sabree
10,664 Points

how did you know to use the querySelector?

Mark Wilkowske
PLUS
Mark Wilkowske
Courses Plus Student 18,131 Points
Mark Wilkowske
Mark Wilkowske
Courses Plus Student 18,131 Points

Andrew mentions this method at around 3.5 minutes into the video and it is also listed in the Teacher's Notes.