Xamarin.iOS Awaitable ShowAlert From: http://tirania.org/monomac/archive/2013/Oct-03.html

Xamarin.iOS Awaitable ShowAlert

async void Demo ()
{
    switch (await ShowAlert ("Title", "Message", "Ok", "Cancel")){
      case 0: // Ok
	        ....
      case 1: // Cancel
          ....
    }
}

// Displays a UIAlertView and returns the index of the button pressed.
public static Task<int> ShowAlert (string title,
                                   string message,
                                   params string [] buttons)
{
    var tcs = new TaskCompletionSource<int> ();
    var alert = new UIAlertView {
        Title = title,
        Message = message
    };
    foreach (var button in buttons)
        alert.AddButton (button);
    alert.Clicked += (s, e) => tcs.TrySetResult (e.ButtonIndex);
    alert.Show ();
    return tcs.Task;
}