public function update(Request $request, $id)
{
$requestArray = $request->all();
$requestArray['parent_id'] = isset($requestArray['parent_id']) && !empty($requestArray['parent_id']) ? $requestArray['parent_id'] : null;
$menu = Menu::findOrFail($id);
$menu->update($requestArray);
$menu->roles()->sync($request->input('roles', []));
return redirect()->route('menu');
}