title: Metro style: how to show filtering options for longlistbox in a proper way
body: <p>I have a large collection of items with several parameters, so i'd like to give a user a possibility to have different filters: like order by time, by alphabet, or by categories.</p>
  
  <p>How should i implement filter selection in Metro style? Should it be a menu items like this, but with "filter by alphabet" instead of "menuitem 1" ?</p>
  
  <p><img src="https://i.stack.imgur.com/RKc3H.png" alt="enter image description here"></p>
  
  <p>Edit: </p>
  
  <p>Some more details: so, assume we have Movie items with 4 fields: name, year of release, genre and main actor's name. I'd like to allow user to set filtering by 1 of those 4 fields. Actually, it is not filtering or sorting, its more like categorizing.</p>