The custom input view controller to use when the receiver becomes the first responder.
- iOS 8.0+
- Mac Catalyst 13.0+
- tvOS 9.0+
The value of this read-only property is
nil. If you want to provide a custom input view controller to replace the system keyboard in your app, redeclare this property as read-write in a
UIResponder subclass.. You can then use this property to manage a custom input view controller. When the receiver becomes the first responder, the responder infrastructure presents the specified input view controller automatically. Similarly, when the receiver resigns its first responder status, the responder infrastructure automatically dismisses the specified input view controller.