iOS 7 Translucent/blurred nav bar how to?

Hi, I would like to know how i can add the iOS 7 translucent blur effect. I would like to add it to my window. Is there a special property for this or is it really simple. Here's my code:

<NavigationWindow id="navWindow">
 
    <Window id="win" class="container">
 
    </Window>
 
</NavigationWindow>