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

Posted by mo ode
mo ode
4,352 Points

Challenge Task 3 of 3 Finally, in the button click handler, apply a background color of "red" to the warning div.

Challenge Task 3 of 3 Finally, in the button click handler, apply a background color of "red" to the warning div. I do not understand. What do I do ?

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

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

});
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

Antony .
Antony .
2,824 Points
Antony .
Antony .
2,824 Points

So previously in your course you were introduced to a property called style, which is equivalent to using CSS but in the form of JavaScript. So following up on the style property there's also other properties that style itself has. If you recap correctly the teacher mentioned the background property. You can use background to set the colour red on the div.

Like this:

var warning = document.getElementById("warning");
var button  = document.getElementById("makeItRed");

button.addEventListener('click', function() {
    warning.style.background = 'red';
});
Antony .
Antony .
2,824 Points
Antony .
Antony .
2,824 Points

I also suggest re-watching the specific video talking about these properties to get some more in-depth information, that is if they don't make sense to you.

Gonzalo Blasco
Gonzalo Blasco
10,405 Points

shouldn't we use 

warning.style.backgroundColor = 'red';

?