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JavaScript JavaScript and the DOM (Retiring) Making Changes to the DOM Appending Nodes

Posted by Tim Graupe
Tim Graupe
6,902 Points

Can't append list item. Receiving console error Uncaught TypeError: addItemButton is null

Just as the title reads, I can't seem to get append the list. Console says the error is on line 34, right where addItemButton is declared. Thanks in advance for any help.

<!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 web page interactive</p>
<button id="toggleList">Hide list</button>
<div class = "list">    
    <p class="description">Things that are purple:</p>
    <input class="description" type="text">
    <button class="description">Change list description</button>
    <ul>
      <li>grapes</li>
      <li>amethyst</li>
      <li>lavender</li>
      <li>plums</li>
    </ul>
      <input class="addItemInput" type="text">
    <button class="addIemButton">Add item</button>
  </div>
    <script src="app.js"></script>
  </body>
</html>

const toggleList = document.getElementById('toggleList');
const listDiv = document.querySelector('.list');
const descriptionInput = document.querySelector('input.description');
const descriptionP = document.querySelector('p.description');
const descriptionButton = document.querySelector('button.description');
const addItemInput = document.querySelector('input.addItemInput');
const addItemButton = document.querySelector('button.addItemButton');

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';
}
                            })

descriptionButton.addEventListener('click', () => {
                        descriptionP.innerHTML = input.value + ":";
                        descriptionInput.value = '';
                        });

addItemButton.addEventListener('click', () => {
     let ul = document.getElementsByTagName('ul')[0];
     let li = document.createElement('li');
      li.textContent = addItemInput.value;
      ul.appendChild(li);
    addItemInput.value = '';
})

1 Answer

Blake Larson
Blake Larson
13,014 Points
Blake Larson
Blake Larson
13,014 Points

You have it spelled addIemButton in the html. Just missing the t.