Returns the last visible interface controller.
- watchOS 4.0+
Use this property to determine which interface controller is currently displayed by the app. For example, in the extension delegate's
handle method for a snapshot request, use this property to determine the user interface's current contents, and make any changes before the snapshot is taken.
Or, when the app is launched due to a Handoff activity, use the
user dictionary to determine what to display. Then use the
visible property to determine whether to push or pop to a different interface controller.
This property contains the following values:
If the app is running in the foreground--The currently presented interface controller.
If the app is in the background--The last interface controller presented by the app.
If the app has just launched--The app's