title: How do I communicate between GlanceController and InterfaceController in Watchkit?
body: <p>According to the <a href="https://developer.apple.com/library/prerelease/ios/documentation/WatchKit/Reference/WKInterfaceController_class/index.html#//apple_ref/occ/instm/WKInterfaceController/willActivate" rel="nofollow">Apple documentation</a> for Watchkit one uses <code>willActivate</code> to update a glance scene with the most up to date information. What is the recommended way to access that "most up to date" information, or in other-words how do I communicate between the <code>GlanceController</code> and the <code>InterfaceController</code>? I am currently using Swift but an answer in Obj-C is fine too. 
  I cannot seem to find this in the documentation. </p>