@Override
	public void changed(ObservableValue<? extends Object> arg0, Object arg1, Object newValue) {
		if (newValue instanceof TreeItem<?>) {
			TreeItem<?> treeItem = (TreeItem<?>) newValue;
                      // EMF Object
			Object value = treeItem.getValue();
			newMenu.getItems().clear();

                       // Get all children of the selected object and create the MenuItem
			Collection<?> collection = editingDomain.getNewChildDescriptors(value, null);
			for (Object object : collection) {
				if (object instanceof CommandParameter) {
					CommandParameter commandParameter = (CommandParameter) object;
					String name = commandParameter.getValue().getClass().getSimpleName().replace("Impl", "");
					MenuItem item = new MenuItem(name);
                                        // Todo: How can I get the Image of the current eobject, maybe via the ItemProvider?
                                        item.setGraphic(new ImageView(""));
					item.setOnAction(event -> {
						int id = EmfUtil.getValueByName(ResourcePackage.eINSTANCE, name);
						Command command = AddCommand.create(editingDomain, value, id,
								ExtendedResourceFactory.eINSTANCE.create(id));
						command.execute();
						eventBroker.post(new EventContext<>(EventTopic.COMMAND_STACK_REFRESH, command));
						treeItem.setExpanded(true);
					});
					newMenu.getItems().add(item);
				}
			}
		}
	}