code: protected void handleOpenItemRequest(final WTree tree, final XmlStringBuilder xml, final String itemId) {
  		TreeItemModel model = tree.getTreeModel();
  		Set<String> selectedRows = new HashSet(tree.getSelectedRows());
  		WTree.ExpandMode mode = tree.getExpandMode();
  
  		// Only want to render the children of the "open item" so only include the open item id in the expanded rows
  		Set<String> expandedRows = new HashSet();
  		expandedRows.add(itemId);
  
  		if (tree.getCustomTree() == null) {
  			List<Integer> rowIndex = tree.getExpandedItemIdIndexMap().get(itemId);
  			paintItem(tree, mode, model, rowIndex, xml, selectedRows, expandedRows);
  		} else {
  			TreeItemIdNode node = tree.getCustomIdNodeMap().get(itemId);
  			paintCustomItem(tree, mode, model, node, xml, selectedRows, expandedRows);
  		}
  	}
docs: Paint the item that was on the open request.
  
  @param tree the WTree to render
  @param xml the XML string builder
  @param itemId the item id to open