1. Tab into the tree control.
  2. Use the up/down arrow keys to change the active descendant.
  3. Use the right/left arrow keys to expand/collapse appropriate nodes.

Note: this example has been updated to account for ARIA's newly defined accessible name calculation, so at the date of this writing (2008/12/14), it does not work as intended with any web browser.

Some focusable content before the ARIA application.

ARIA Tree Example

More focusable content after the ARIA application.