Create sidebar menu xxBundle\Model\MenuItemModel contains 16 abstract methods and must therefore be declared abstract or ...

[Guiriou]

I would like to create a menu sidebar navigation. I implemented the interface but I had this error:
xxBundle\Model\MenuItemModel contains 16 abstract methods and must therefore be declared abstract or implement the remaining methods (Avanzu\AdminThemeBundle\Model\MenuItemInterface::getIdentifier, Avanzu\AdminThemeBundle\Model\MenuItemInterface::getLabel, Avanzu\AdminThemeBundle\Model\MenuItemInterface::getRoute, ...)

My code Model:

<?php
namespace jpBundle\Model

use Avanzu\AdminThemeBundle\Model\MenuItemInterface as ThemeMenuItem;

class MenuItemModel implements ThemeMenuItem {
	// ...
	// implement interface methods
	// ...
}

My code Event Listener:

<?php
namespace xxBundle\EventListener;

// ...

use xxBundle\Model\MenuItemModel;
use Avanzu\AdminThemeBundle\Event\SidebarMenuEvent;
use Symfony\Component\HttpFoundation\Request;

class MyMenuItemListListener {

	// ...

	public function onSetupMenu(SidebarMenuEvent $event) {

		$request = $event->getRequest();

        foreach ($this->getMenu($request) as $item) {
            $event->addItem($item);
        }

	}

	protected function getMenu(Request $request) {
		// Build your menu here by constructing a MenuItemModel array
		$menuItems = array(
            $blog = new MenuItemModel('ItemId', 'ItemDisplayName', 'jp_admin_abonnement', array(/* options */), 'iconclasses fa fa-plane')
        );

        // Add some children

        // A child with an icon
        $blog->addChild(new MenuItemModel('ChildOneItemId', 'ChildOneDisplayName', 'child_1_route', array(), 'fa fa-rss-square'));

        // A child with default circle icon
        $blog->addChild(new MenuItemModel('ChildTwoItemId', 'ChildTwoDisplayName', 'child_2_route'));
		return $this->activateByRoute($request->get('_route'), $menuItems);
	}

	protected function activateByRoute($route, $items) {

        foreach($items as $item) {
            if($item->hasChildren()) {
                $this->activateByRoute($route, $item->getChildren());
            }
            else {
                if($item->getRoute() == $route) {
                    $item->setIsActive(true);
                }
            }
        }

        return $items;
    }

}

Can you help me please?