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JavaScript JavaScript and the DOM (Retiring) Responding to User Interaction Event Delegation

matthew glen
matthew glen
14,153 Points
Posted by matthew glen
matthew glen
14,153 Points

Can I get this explained please, don't understand what i've missed.

In the listener that has been added to the section element, ensure that the text input elements are the only children that trigger the background-changing behavior.

index.html 
<!DOCTYPE html>
<html>
    <head>
        <title>JavaScript and the DOM</title>
    </head>
    <link rel="stylesheet" href="style.css" />
    <body>
        <section>
            <h1>Making a Webpage Interactive</h1>
            <p>JavaScript is an exciting language that you can use to power web servers, create desktop programs, and even control robots. But JavaScript got its start in the browser way back in 1995.</p>
            <hr>
            <p>Things to Learn</p>
            <ul>
                <li>Item One: <input type="text"></li>
                <li>Item Two: <input type="text"></li>
                <li>Item Three: <input type="text"></li>
                <li>Item Four: <input type="text"></li>
            </ul>
            <button>Save</button>
        </section>
        <script src="app.js"></script>
    </body>
</html>
app.js 
let section = document.getElementsByTagName('section');

section.addEventListener('click', (e) => {
  if(e.target.tagName == 'INPUT') {
    e.target.style.backgroundColor = 'rgb(255, 255, 0)';
  }
});

1 Answer

Stuart Wright
Stuart Wright
41,118 Points
Stuart Wright
Stuart Wright
41,118 Points

Your function is correct, but you just need to add [0] to the end of the first line, so that the section variable is equal to the first section element:

let section = document.getElementsByTagName('section')[0];

Otherwise, getElementsByTagName returns a collection of elements (even though in this case the collection would only contain one element, since the page contains only one section).