I have an iOS app that supports multiple scenes on the iPad, and which has an "Open in Another Window" feature which creates a new window scene. I would like to bring this feature to the iPhone Duo.
On the iPhone Duo, of course, creating new windows is only supported when the device is open; when it is closed, creating new windows does not work. (If you try, an error is thrown.)
Until now, the way I have checked whether my "Open in Another Window" feature should be available is to check to see if UIApplication.shared.supportsMultipleScenes is true. This has always returned false for previous iPhones and true for iPads.
Unfortunately, however, this does not work as expected on the iPhone Duo. On the Duo, I would expect supportsMultipleScenes to return true when the device is open, but false when it is closed. This is not the case: it returns true for all poses. (Filed as #FB24948411 as this doesn't seem right to me.) So it does not help me decide whether the feature should be available.
UIWindowScene.ActivationAction does work as expected when used in a menu, with the action auto-hiding when the Duo is in the closed pose. In my app, though, I need more than just an auto-hiding menu item; I need to check whether creating a new window is currently possible for certain UI availability decisions.
What, then, is the correct way of checking this, if it's not with supportsMultipleScenes? Given that UIWindowScene.ActivationAction is able to hide itself, I assume there is some better way of checking that I have missed.