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

kingdavid igbayilola
kingdavid igbayilola
8,678 Points
Posted by kingdavid igbayilola
kingdavid igbayilola
8,678 Points

event listener DOM

warning = document.body.stye.backgroundColor(''red');

Am getting a syntax error here

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

button.addEventListener('click', ()=> {
    warning = document.body.style.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>

2 Answers

Steven Parker
Steven Parker
231,236 Points
Steven Parker
Steven Parker
231,236 Points

The "backgroundColor " is not a method you can call, but it is a property that you can assign to:

    document.body.style.backgroundColor = "red";
kingdavid igbayilola
kingdavid igbayilola
8,678 Points
kingdavid igbayilola
kingdavid igbayilola
8,678 Points

how can i go about giving class "warning" a background color red

Steven Parker
Steven Parker
231,236 Points
Steven Parker
Steven Parker
231,236 Points

You can assign any specifc element instead of the document body the same way:

    warning.style.backgroundColor = "red";

And "warning" is not a class, but an id attribute.

Thomas Tilton-Heylin
Thomas Tilton-Heylin
12,098 Points
Thomas Tilton-Heylin
Thomas Tilton-Heylin
12,098 Points 
$('#makeItRed').click(function() {
$('#warning').css('backgroundColor', 'red')
});