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JavaScript JavaScript and the DOM (Retiring) Responding to User Interaction Adding an Event Listener

Posted by Miguel Adan
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Miguel Adan
Front End Web Development Techdegree Student 2,621 Points

Whats an empty function

Its asking to pass on an empty function as the second parameter. What's an empty function?

app.js 
const warning = document.getElementById("warning");
let button = document.getElementById('makeItRed');


button.addEventListener('click', null);
index.html 
<!DOCTYPE html>
<html>
    <head>
        <title>Adding an Event Listener</title>
    </head>
    <link rel="stylesheet" href="style.css" />
    <body>
        <div id="warning">
            Warning: My background should be red!
        </div>
        <button id="makeItRed">Make It Red!</button>
        <script src="app.js"></script>
    </body>
</html>

1 Answer

paulscanlon
PLUS
paulscanlon
Courses Plus Student 26,735 Points
paulscanlon
paulscanlon
Courses Plus Student 26,735 Points

Hey Miguel

To pass it an empty function try this.

const warning = document.getElementById("warning");
let button = document.getElementById('makeItRed');


button.addEventListener('click', function() {

});

Null means that something doesn't exist.

Happy coding

Paul