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

Posted by Khumoyunmirzo Nosirov
Khumoyunmirzo Nosirov
8,689 Points

I couldn't find the error , can Anyone help me?

We have a page with 3 buttons. Our goal is to apply the spinElement callback to btn1, btn2, and btn3. The spinElement function should be triggered on the click event. Modify the code in the app.js file to add the event listener to every button.

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";
}


btn1.addEventElement('click', spinElement);
btn2.addEventElement('click', spinElement);
btn3.addEventElement('click', spinElement);
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

Byron Injeeli
.a{fill-rule:evenodd;}techdegree seal-36
Byron Injeeli
Full Stack JavaScript Techdegree Graduate 25,639 Points

Hi Khumoyunmirzo, you should be using the addEventListener method to add callback functions to HTML elements:

btn1.addEventListener('click', spinElement);
Khumoyunmirzo Nosirov
Khumoyunmirzo Nosirov
8,689 Points

What did I do?

Byron Injeeli
.a{fill-rule:evenodd;}techdegree seal-36
Byron Injeeli
Full Stack JavaScript Techdegree Graduate 25,639 Points

Khumoyunmirzo, you were using addEventElement instead of addEventListener.

Khumoyunmirzo Nosirov
Khumoyunmirzo Nosirov
8,689 Points
Khumoyunmirzo Nosirov
Khumoyunmirzo Nosirov
8,689 Points

thank you soooo much , you really helped me!

Byron Injeeli
.a{fill-rule:evenodd;}techdegree seal-36
Byron Injeeli
Full Stack JavaScript Techdegree Graduate 25,639 Points

No problem - could you please select my answer as the correct answer for this question? Thanks!