How to keyboard down or up between dropdown options

To enable keyboard navigation between dropdown options using JavaScript, you can implement the following steps:

1. Add an event listener to the dropdown element to detect keyboard events.
2. Check for arrow key presses (up or down) using the event object.
3. Get the current selected option's index.
4. Based on the arrow key pressed, increment or decrement the index.

 <script>
  const dropdown = document.getElementById('myDropdown');
  let selectedIndex = -1;

  dropdown.addEventListener('keydown', (event) => {
   const key = event.key;
  
   if(key === 'ArrowUp' && selectedIndex > 0) {
    selectedIndex--;
   } else if(key === 'ArrowDown' && selectedIndex < dropdown.options.length - 1) {
    selectedIndex++;
   }
  
   dropdown.selectedIndex = selectedIndex;
  });
 </script>

1. The code adds an event listener to the dropdown element to detect keydown events.
2. It checks if the key pressed is ArrowUp and the current selected index is greater than 0, then decrements the selectedIndex variable.
3. If the key pressed is ArrowDown and the current selected index is less than the last option index, it increments the selectedIndex variable.
4. Finally, it sets the selectedIndex as the selected option index, ensuring it stays within the bounds of the available options.

Using the Tab key to navigate between dropdown options#

To enable keyboard navigation between dropdown options using the Tab key, you can implement the following steps:

1. Add an event listener to the dropdown element to detect keydown events.
2. Check for the Tab key press using the event object.
3. Get the current selected option's index.
4. If the Tab key is pressed while the dropdown is focused, move the focus to the next tabbable element on the page.
5. This allows the default behavior of the Tab key to handle the navigation between dropdown options.

<script>
 const dropdown = document.getElementById('myDropdown');
 dropdown.addEventListener('keydown', (event) => {
  const key = event.key;
  
  if(key === 'Tab' && dropdown === document.activeElement) {
    
    event.preventDefault();
    document.getElementById('nextElementId').focus();
  }
 });
</script>

1. The code adds an event listener to the dropdown element to detect keydown events.
2. It checks if the key pressed is the Tab key and if the dropdown is currently focused. If both conditions are met, it prevents the default behavior of the Tab key (moving to the next element) and manually focuses on the next element on the page.