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JavaScript

Jake Kobs
Jake Kobs
9,215 Points
Posted by Jake Kobs
Jake Kobs
9,215 Points

addEventListener() - Problem with button clicks setting background color

Everything in my code looks fine to me, but when I click on any of the buttons, the body color of the webpage doesn't change. Here's my JavaScript code:

const body = document.getElementsByTagName('body');
const button = document.getElementsByTagName("button");


document.addEventListener("click", (event) => {
    console.log(event.target);

});
button.addEventListener("click", (event) => {
    if(event.target.tagName == "BUTTON"){
        if(event.target.className == "red"){
            body.style.background = "red";
}
        if(event.target.className == "blue"){
            body.style.background = "blue";
        }
        if(event.target.className == "orange"){
            body.style.background = "orange";
        }
        if(event.target.className == "yellow"){
            body.style.background = "yellow";
        }

}
});

HTML code:

<!DOCTYPE html>
<html>
<head>
<title>Practice JS</title>
<link rel="stylesheet" href="cssPrac.css">

</head>
<body> 
        <div class="container">
        <header>
            <h1>JavaScript Practice</h1>
            <div class="bList">
                <button class="red">Color to red</button>
                <button class="blue">Color to blue</button>
                <button class="orange">Color to orange</button>
                <button class="yellow">Color to yellow</button>
            </div>

        </header>
    </div>



<script src="jsPrac.js"></script>

</body>
</html>

1 Answer

Steven Parker
Steven Parker
231,007 Points
Steven Parker
Steven Parker
231,007 Points

The "addEventListner" method is only available on individual elements, but "button" is assigned to an HTMLCollection returned by the selector method.

Similarly, "body" is also assigned to an HTMLCollection, but only individual elements have a "style" property.

Jake Kobs
Jake Kobs
9,215 Points
Jake Kobs
Jake Kobs
9,215 Points

Thank you very much, Steven! All I had to do was change .getElementsByTagName to .querySelector and create class names for the body and pointed to the parent of the buttons class name.

Steven Parker
Steven Parker
231,007 Points
Steven Parker
Steven Parker
231,007 Points

That's a good fix, and another one would be to add indexing (...[0]) to the collection selector to get just the first element from it.