Continue to look at the new goodies and goodies from WWDC 2017 Today, we learn about the changes on the screen side's behavior in iOS 11 . Let's go diving.
What we're talking about here is the behavior when a user is leaving offscreen. This may be the user trying to pull down Notification Center from the top, or retrieve Control Center at the bottom of the screen.
During iOS ] releases, the system has looked at the visibility of the status line to determine how to behave in these cases.
If we configured one of our display controllers to hide status bar the system will display a small "fan" interface with an arrow that the user needs to drag again Message Center or Control Center will be displayed:
It's probably not the best way for us to "tell" the system to look at the visibility of the status bar  do here.  I iOS 11 we've got a great new way to describe how our app will behave when the user performs these (
-> UIRectEdge [ return . the bottom }
In this way we can describe exactly which edges on the screen we would like to allow the system certificates to behave as "normal" and we want to be exposed to another drag. Neat!
Finally, if the condition of our display controls ever changes enough to guarantee a change in this behavior, we may call the following new feature to update it: