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

Gareth Partridge
Gareth Partridge
13,421 Points
Posted by Gareth Partridge
Gareth Partridge
13,421 Points

Currently, the event listener applies a yellow background color to the section element and its child elements when click

Currently, the event listener applies a yellow background color to the section element and its child elements when clicked. Add a condition that changes the background of the <input> elements only.

I honestly have no idea on this one, any suggestions ?

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

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

6 Answers

Allan Collado
Allan Collado
10,248 Points
Allan Collado
Allan Collado
10,248 Points 
let section = document.getElementsByTagName('section')[0];

section.addEventListener('click', (e) => {

  if(e.target.tagName === 'INPUT'){
    e.target.style.backgroundColor = 'rgb(255, 255, 0)';
  }
});
Safae Merigh
Safae Merigh
9,827 Points

Why do we need "===" instead of just "=="?

Max van den Berge
Max van den Berge
6,506 Points

this worked, i was struggling to :)

Alan Lane
Alan Lane
9,156 Points
Alan Lane
Alan Lane
9,156 Points

WOW! I got lucky, this is the solution that I finally got to work:

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

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

Flora Yin
Flora Yin
6,792 Points
Flora Yin
Flora Yin
6,792 Points

Could someone please explain why "INPUT" is needed here instead of "input"?

Steven Parker
Steven Parker
231,268 Points
Steven Parker
Steven Parker
231,268 Points

As I told "anywayiam", you should always start a fresh new question instead of posting one as an "answer".

But quoting from the MDN page on tagName:

For DOM trees which represent HTML documents, the returned tag name is always in the canonical upper-case form. For example, tagName called on a <div> element returns "DIV".

Steven Parker
Steven Parker
231,268 Points
Steven Parker
Steven Parker
231,268 Points

You'll need to enclose the color assignment in a condtional ("if") statement. The "if" should check the tagName attribute of the clicked item (e.target) to see if it is an "INPUT".

anywayiam
anywayiam
3,970 Points
anywayiam
anywayiam
3,970 Points

I have the same problem. It doesn't work.

<!DOCTYPE html>
<html>
    <head>
        <title>JavaScript and the DOM</title>
    </head>
    <link rel="stylesheet" href="style.css" />
    <body>
        <section id='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>
    </body>
</html>

let section = document.getElementById('section');

section.addEventListener('click', (event) => {
  if(event.target.tagName == 'INPUT') {
  event.target.style.backgroundColor = 'rgb(255, 255, 0)';
  }
});
Steven Parker
Steven Parker
231,268 Points
Steven Parker
Steven Parker
231,268 Points

In future, always start a fresh new question instead of posting one as an "answer".

But for this challenge you only need to add a conditional to the event handler. You should not make any changes to the other code including the HTML portion.

Sean Gibson
Sean Gibson
38,363 Points
Sean Gibson
Sean Gibson
38,363 Points

I was running around in circles for a while on this one and found that my mistake was typing "tagname" instead of "tagName". Just in case this may help someone