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JavaScript JavaScript and the DOM (Retiring) Responding to User Interaction Functions as Parameters

temp.js is ok.. I have an "app.js:33 Uncaught TypeError: Cannot read property 'addEventListener' of null at app.js:33"

I get that error in the console log. my temp.js seems to be OK, so far. so, what am i missing on line 33?

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');
const removeItemButton = document.querySelector('button.removeItemButton');

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 = descriptionInput.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 = '';
});

removeItemButton.addEventListener('click', () => {
  let ul = document.getElementsByTagName('ul')[0];
  let li = document.querySelector('li:last-child');
  ul.removeChild(li);
});
Reggie Williams
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Reggie Williams
Treehouse Teacher

Hey Amy Tomey have you changed the HTML? I'm not getting any error for that eventListener but that error usually means the selector isn't selecting anything

1 Answer

HI Amy. You have to check your HTML files and make sure the DOM element you are trying to select using your event Listener has no typing errors. In essence it should correspond in spelling to how you invoked it in app.js.