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JavaScript JavaScript and the DOM (Retiring) Traversing the DOM Challenge: Using nextElementSibling

Posted by Anthony Smith
Anthony Smith
9,897 Points

nextElementSibling not code not working

So I've completed the challenge to the best of my ability and my down button is still not firing. 

<!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 type="text" class="description">
      <button class="description">Change list description</button>
      <ul>
        <li>grapes
          <button class="up">Up</button>
          <button class="down">Down</button>
          <button class="remove">Remove</button>

        </li>
        <li>amethyst
          <button class="up">Up</button>
          <button class="down">Down</button>
          <button class="remove">Remove</button>
        </li>
        <li>lavender
          <button class="up">Up</button>
          <button class="down">Down</button>
          <button class="remove">Remove</button>
        </li>
        <li>plums
          <button class="up">Up</button>
          <button class="down">Down</button>
          <button class="remove">Remove</button>
        </li>
      </ul>
      <input type="text" class="addItemInput">
      <button class="addItemButton">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 listUl = listDiv.querySelector('ul');
const addItemInput = document.querySelector('input.addItemInput');
const addItemButton = document.querySelector('button.addItemButton');

listUl.addEventListener('click', (event) => {
  if (event.target.tagName == 'BUTTON') {
    if (event.target.className == 'remove') {
    let li = event.target.parentNode;
    let ul = li.parentNode;
    ul.removeChild(li);
    }
    if (event.target.className == 'up') {
      let li = event.target.parentNode;
      let prevLi = li.previousElementSibling;
      let ul = li.parentNode;
      if (prevLi) {
      ul.insertBefore(li, prevLi);
      }
    if (event.target.className == 'down') {
      let li = event.target.parentNode;
      let nextLi = li.nextElementSibling;
      let ul = li.parentNode;
      if (nextLi) {
      ul.insertBefore(nextLi, li);
      }
    }
   }
  }
});


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 = '';
});

1 Answer

KRIS NIKOLAISEN
KRIS NIKOLAISEN
54,967 Points

You have a bracketing issue. There should be one more closing bracket at the end here:

   if (event.target.className == 'up') {
      let li = event.target.parentNode;
      let prevLi = li.previousElementSibling;
      let ul = li.parentNode;
      if (prevLi) {
      ul.insertBefore(li, prevLi);
      }
    }

And one less closing bracket at the very end here: 

 if (event.target.className == 'down') {
      console.log("down click")
      let li = event.target.parentNode;
      let nextLi = li.nextElementSibling;
      let ul = li.parentNode;
      if (nextLi) {
      ul.insertBefore(nextLi, li);
      }

   }
  }
});