table = new AjaxFallbackDefaultDataTable<BuildableComponentDto, String>("components", getColumns(), getModel(),
        100) {
    @Override
    protected Item<BuildableComponentDto> newRowItem(String id, int index, IModel<BuildableComponentDto> model) {
        Item<BuildableComponentDto> components = new Item<BuildableComponentDto>(id, index, model) {
            @Override
            public void onEvent(IEvent<?> event) {
                super.onEvent(event);
                if (event.getPayload() instanceof ComponentChangedEvent) {
                    ComponentChangedEvent payload = (ComponentChangedEvent) event.getPayload();
                    BuildableComponentDto buildableComponentDto = payload.getBuildableComponentDto();
                    if (buildableComponentDto.getId().equals(getModelObject().getId())) {
                        setModelObject(payload.getBuildableComponentDto());
                        payload.getTarget().add(this);
                        event.stop();
                    }
                } else if (event.getPayload() instanceof ComponentDeletedEvent) {
                    ComponentDeletedEvent payload = (ComponentDeletedEvent) event.getPayload();
                    BuildableComponentDto buildableComponentDto = payload.getBuildableComponentDto();
                    AjaxRequestTarget target = payload.getTarget();
                    if (buildableComponentDto.getId().equals(getModelObject().getId())) {
                        this.setVisible(false);
                        target.add(this);
                        event.stop();
                    }
                }
            }
        };
        components.setMarkupId(ROW_ID_PREFIX + model.getObject().getId());
        components.setOutputMarkupId(true);
        return components;
    }
};

public void addItem(AjaxRequestTarget target, BuildableComponentDto buildableComponentDto) {
    try {
        RefreshingView datagrid = (RefreshingView) ReflectUtils.getInstance().getFieldValue(
                table, "datagrid");
        Method method = RefreshingView.class.getDeclaredMethod("newItemFactory");
        method.setAccessible(true);
        IItemFactory factory = (IItemFactory) method.invoke(datagrid);
        Item item = factory.newItem(buildableComponentDto.getId(), new Model(buildableComponentDto));
        datagrid.add(item);
        target.prependJavaScript(String.format(
                "var item=document.createElement('%s');item.id='%s';"
                        + "Wicket.$('%s').getElementsByTagName(\"tbody\")[0].appendChild(item);", "tr", item.getMarkupId(),
                table.getMarkupId()));
        target.add(item);
    } catch (Exception e) {
        throw new RuntimeException(e);
    }
}