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

Posted by Eniola Tijani
Eniola Tijani
3,440 Points

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

welp!!

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

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

;
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>

3 Answers

Piotr Manczak
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Piotr Manczak
Front End Web Development Techdegree Graduate 28,940 Points
Piotr Manczak
.a{fill-rule:evenodd;}techdegree seal-36
Piotr Manczak
Front End Web Development Techdegree Graduate 28,940 Points

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

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

if (e.target.tagName == 'INPUT') {

e.target.style.backgroundColor = 'rgb(255, 255, 0)';

}

});

Linas Mackonis
Linas Mackonis
7,071 Points
Linas Mackonis
Linas Mackonis
7,071 Points

Hi, this should work:

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

for(let i = 0; i < input.length; i += 1) {
input[i].addEventListener('click', (e) => {
  e.target.style.backgroundColor = 'rgb(255, 255, 0)';
});

}
Michael Barlow
Michael Barlow
34,317 Points
Michael Barlow
Michael Barlow
34,317 Points

You're also referencing event from within the callback, which is (probably) undefined in that scope. You've defined the event argument as e, so use that to get a reference to the target: e.target...