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JavaScript JavaScript and the DOM (Retiring) Getting a Handle on the DOM A Simple Example

Nebojsa Stevanovic
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Nebojsa Stevanovic
Full Stack JavaScript Techdegree Student 9,620 Points
Posted by Nebojsa Stevanovic
.a{fill-rule:evenodd;}techdegree
Nebojsa Stevanovic
Full Stack JavaScript Techdegree Student 9,620 Points

Hello.. i keep getting this error " java.js:3 Uncaught TypeError: Cannot read property 'addEventListener' of null "

Hello.. i keep getting error " Cannot read property 'addEventListener' of null "

i have spent 3 hours staring in the screen trying to see what's wrong but i gave up.. coud someone tell me whats wrong in this :

<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <link rel='stylesheet' href='style.css'> <script src='java.js'></script> <title>Document</title> </head>

<body> <h1 id='myHeading'>JavaScript and DOM</h1> <p> Making a web page interactive</p> </body> </html>

and my javascript code :

const myHeading = document.getElementById('myHeading');

myHeading.addEventListener('click', () => { myHeading.style.color = 'red'; });

1 Answer

KRIS NIKOLAISEN
KRIS NIKOLAISEN
54,967 Points

You are receiving that error because the script runs before the document finishes loading. I moved the script to the end of the body and it runs from there.

<body>
  <h1 id='myHeading'>JavaScript and DOM</h1>
  <p> Making a web page interactive</p>
  <script src='java.js'></script>
</body>