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

aliceinwonderland
aliceinwonderland
7,679 Points
Posted by aliceinwonderland
aliceinwonderland
7,679 Points

I'm not sure I understand the question. Here is my code. It is wrong.

Perhaps I don't understand the question?

app.js 
const warning = document.getElementById("warning");
let button = document.getElementById('makeItRed');
button.addEventListener('click', () => {
  warning.backgroundColor = 'red';
});
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>
Charlie Harcourt
Charlie Harcourt
8,046 Points

Could you link the question please.

Adam N
Adam N
70,280 Points

there's a link to the relevant challenge to the right of the breadcrumbs

Charlie Harcourt
Charlie Harcourt
8,046 Points

Ah yes my apologies I didn't see that :D

3 Answers

aliceinwonderland
aliceinwonderland
7,679 Points
aliceinwonderland
aliceinwonderland
7,679 Points

i know the func structure wasn't the problem. i was just explaining how i see the difference between the two ways to write a function after charlie showed the alternative way. i think he was just giving some more material to learn after my error was solved by you, adam.

Charlie Harcourt
Charlie Harcourt
8,046 Points
Charlie Harcourt
Charlie Harcourt
8,046 Points

There is also another way of doing this code for the last two lines:

So instead of:

button.addEventListener('click', () => { warning.backgroundColor = 'red'; });

It could be:

button.addEventListener('click', function(){ warning.style.backgroundColor = 'red'; });

Happy coding :)

aliceinwonderland
aliceinwonderland
7,679 Points
aliceinwonderland
aliceinwonderland
7,679 Points

thank you so much. i see the fat arrow way is not much different--you just omit the word "function" and insert a fat arrow between the parentheses and the opening bracket.

Adam N
Adam N
70,280 Points

The structure of your func was not the problem w/ your code.

Charlie Harcourt
Charlie Harcourt
8,046 Points

It was just an alternative way of doing it. You had already answered the question It's just nice to know that there are two answers to the question.

:)

Adam N
Adam N
70,280 Points
Adam N
Adam N
70,280 Points

The proper syntax to change the styling of an element using vanilla js is:

element.style.cssProperty = 'whatever'

Let me know if this helps here

aliceinwonderland
aliceinwonderland
7,679 Points
aliceinwonderland
aliceinwonderland
7,679 Points

thank you, adam. i forgot the .style part!