protected void onClick(Event event) {
XEvent e = event.<XEvent> cast();
TreeNode<M> node = findNode(event.getEventTarget().<Element> cast());
if (node != null) {
Element jointEl = view.getJointElement(node);
if (jointEl != null && e.within(jointEl)) {
toggle((M) node.getModel());
}
Element checkEl = view.getCheckElement(node);
if (checkable && checkEl != null && isEnabled() && e.within(checkEl)) {
onCheckClick(event, node);