public function fill()
    {
        // Write the position value to the pivot table
        if (isset($this->pivot->position)) {
            $this->pivot->position = request('position');
            $this->pivot->save();

        // Write position value to the item
        } elseif (isset($this->item->position)) {

            // Visiblity may be set at the same time and would be ignored otherwise
            if (Request::has('public')) {
                $this->item->public = request('public');
            }

            // Do position
            $this->item->position = request('position');
        }
    }