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JavaScript Callback Functions in JavaScript Callbacks and the DOM Callbacks with DOM Elements

Posted by Sean Modd
Sean Modd
4,688 Points

Goal: Apply the spinElement callback to btn1, btn2, and btn3. The spinElement function should trigger on click event!

Please help!

app.js 
const btn1 = document.getElementById("button1");
const btn2 = document.getElementById("button2");
const btn3 = document.getElementById("button3");

function spinElement(event) {
  //Applies spinning animation to button element
  event.target.className = "spin";
}
index.html 
<!DOCTYPE html>
<html lang="en">
    <head>
        <title></title>
        <link rel='stylesheet' href='styles.css'>
    </head>
    <body>
        <section >
            <button id='button1'>Button 1</button>
            <button id='button2'>Button 2</button>
            <button id='button3'>Button 3</button>
        </section>
        <script src='app.js'></script>
    </body>
</html>

2 Answers

Brandon White
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Brandon White
Full Stack JavaScript Techdegree Graduate 35,771 Points
Brandon White
.a{fill-rule:evenodd;}techdegree seal-36
Brandon White
Full Stack JavaScript Techdegree Graduate 35,771 Points

Hi Sean,

What you'll want to do is call the addEventListener method on the button elements. The addEventListener has at least three parameters. The first is a string which represents the event you want the browser to listen for, the second is a callback function (or a function that is called once the event is triggered).

Here's a link to an article about the addEventListener method. https://developer.mozilla.org/en-US/docs/Web/API/EventTarget/addEventListener

Hopefully, that info is enough of a tip to get you looking in the right direction. If you end up needing a bit more of a hint than that, let me know, and I'll do my best.

Here's another hint: You don't need to alter any of the code presented to you by the challenge. You'll simply add new statements to the code that's already there.

Ayodeji Adediran
Ayodeji Adediran
2,736 Points
Ayodeji Adediran
Ayodeji Adediran
2,736 Points

{button}.addEventListener(‘click’, (e)=>{ spinElement(e) })