public void render(final Treeitem item, Object data) throws Exception {
Task task = (Task) data;
item.setOpen(isOpened(task));
if (task instanceof TaskContainer) {
final TaskContainer container = (TaskContainer) task;
IExpandListener expandListener = new IExpandListener() {
@Override
public void expandStateChanged(boolean isNowExpanded) {
item.setOpen(isNowExpanded);
}