@Override
		public void handleEvent (final Event event) {
			final TreeItem root = (TreeItem) event.item;
			TreeItem [] items = root.getItems ();
			for (int i= 0; i<items.length; i++) {
				if (items [i].getData () != null) return;
				items [i].dispose ();
			}
			File file = (File) root.getData ();
			File [] files = file.listFiles ();
			if (files == null) return;
			for (int i= 0; i<files.length; i++) {
				TreeItem item = new TreeItem (root, 0);
				item.setText (files [i].getName ());
				item.setData (files [i]);
				if (files [i].isDirectory()) {
					new TreeItem (item, 0);
				}
			}
		}