In the application, we use the function of multi display.
However, it is not always used during application startup, and only for specific screens, dedicated display is performed.
"UIWindow.Screen = null" is executed when the specific display is completed, and it is displayed in iOS normal display.
However, when it is currently executed, an exception is generated.
The following is an exception:
Value cannot be null.
Parameter name: value
Considering the iOS sample program and the things that have been working so far,
it seems that there have been some changes in iOS 12,
but would someone tell me the information?