title: MvvmCross iOS similar to IMvxAndroidCurrentTopActivity
body: <p>I'm trying to create a Plugin in MvvmCross that uses the UIActionSheet. But to use it I need to have the top View in iOS. I found in Android the IMvxAndroidCurrentTopActivity but i could not find a similar in iOS. Is there anything that i can use like this in iOS?</p>
  
  <pre><code>var activity = Mvx.Resolve&lt;IMvxAndroidCurrentTopActivity&gt;().Activity;
  if (activity == null)
  {
     throw new Exception("Cannot get current top activity");
  }
  </code></pre>