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JavaScript JavaScript and the DOM (Retiring) Making Changes to the DOM Styling Elements

Carla Kroll
Carla Kroll
7,906 Points

Fully nested list doesn't hide. Only the first paragraph

For some reason only the paragraph 'Things that are purple' hide onclick.

<body>
    <h1 id="myHeading">JavaScript and the DOM</h1>
    <p>Making a web page interactive</p> 
    <button id="toggleList">Hide List</button>
    <div class="listDiv">
        <p class="description">Things that are purple:</p>
        <input type="text" class="description">
        <button class="description">Change List Description</button>
        <ul>
          <li>grapes</li>
          <li>amethyst</li>
          <li>lavender</li>
          <li>plums</li>
        </ul>
    </div>
    <script src="app.js"></script>
  </body>
const toggleList = document.getElementById('toggleList');
const listDiv = document.getElementsByClassName('listDiv');

toggleList.addEventListener('click', () => {

     listDiv.style.display = none;
});
Carla Kroll
Carla Kroll
7,906 Points

I fixed this issue by changing the const listDiv to a querySelector.

1 Answer

Steven Parker
Steven Parker
231,271 Points

I see two issues here.

The getElementsByClassName function returns a collection, not a single element. To get a single element you can provide an index:

const listDiv = document.getElementsByClassName('listDiv')[0];

Then, when setting the value for the display property, the value is a literal string and should be enclosed in quotes:

     listDiv.style.display = "none";