Number of items per selection issue

Hi. I wanna do something like this: 

 let data: [[String]] = [
            ["Communities", "Resources"],
            ["All", "Popular", "Newest", "Nearest"]
        ]

But the app crashes. How can I achieve this? 

Thanks!

PS. I don't want this ;)
 let data: [[String]] = [
            ["Communities", "Resources","",""],
            ["All", "Popular", "Newest", "Nearest"]
        ]