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JavaScript

Nuradin Sheikh
Nuradin Sheikh
6,211 Points
Posted by Nuradin Sheikh
Nuradin Sheikh
6,211 Points

Why do I keep getting the error "Cannot read property 'addEventListener' of null"?

const toggleList = document.getElementById('toggleList'); const listDiv = document.querySelector('.List');

const input = document.querySelector('input'); const p = document.querySelector('p.description'); const button = document.querySelector('button');

toggleList.addEventListener('click', () => { if (listDiv.style.display == "none"){ toggleList.textContent = "Hide List"; listDiv.style.display = "block"; } else{ toggleList.textContent = "show List"; listDiv.style.display = "none" } });

button.addEventListener('click', () => { p.innerHTML = input.value + ':'; 

                    });

index.html:

<!DOCTYPE html> <html> <head> <title>JavaScript and the Dom</title> <link rel = "stylesheet" href = "css/style.css">

</head> <body>

<h1 id = "myHeading">JavaScript and the Dom</h1> <p>Making a webpage interactive</p> <button id = "toogleList">Hide List</button>

<div class = "List"> <p class = "description">Things that are purple</p> <input type= "text" class = "description"> <button class = "description">Change List of description</button> <ul> <li>grapes</li> <li>amethyst</li> <li>lavender</li> <li>Plums</li> </ul> </div> <script src="app.js"></script> </body>

</html>

1 Answer

KRIS NIKOLAISEN
KRIS NIKOLAISEN
54,971 Points

You have a misspelling in index.html. You have an id of "toogleList" instead of "toggleList"