private function addToClipboard(ActionEvent $event)
    {
        $actionName  = $event->getAction()->getName();
        $environment = $event->getEnvironment();
        $input       = $environment->getInputProvider();
        $clipboard   = $environment->getClipboard();

        $parentIdRaw = $input->getParameter('pid');
        if ($parentIdRaw) {
            $parentId = ModelId::fromSerialized($parentIdRaw);
        } else {
            $parentId = null;
        }

        if (!($clipboardActionName = $this->translateActionName($actionName))) {
            return;
        }

        if ('create' === $actionName) {
            if ($this->isAddingAllowed($environment)) {
                return;
            }

            $providerName = $environment->getDataDefinition()->getBasicDefinition()->getDataProvider();
            $item         = new UnsavedItem($clipboardActionName, $parentId, $providerName);

            // Remove other create items, there can only be one create item in the clipboard or many others
            $clipboard->clear();
        } else {
            $modelIdRaw = $input->getParameter('source');
            $modelId    = ModelId::fromSerialized($modelIdRaw);

            // If edit several don´t remove items from the clipboard.
            $this->removeItemsFromClipboard($event);

            // Only push item to clipboard if manual sorting is used.
            if (Item::COPY === $clipboardActionName && !ViewHelpers::getManualSortingProperty($environment)) {
                return;
            }

            // create the new item
            $item = new Item($clipboardActionName, $parentId, $modelId);
        }

        // If edit several don´t redirect do home and push item to the clipboard.
        if ('select' === $input->getParameter('act')) {
            $clipboard->push($item)->saveTo($environment);

            return;
        }

        // Let the clipboard save it's values persistent.
        $clipboard->clear()->push($item)->saveTo($environment);

        ViewHelpers::redirectHome($environment);
    }