Since iOS 7, the navigation bar and toolbar[0] in a UINavigationController
are designed to render atop the content of the current UIViewController
. In order to prevent these bars from occluding the contents of the view, UINavigationController
will (under certain conditions) automatically reach down the view hierarchy and adjust the insets of the primary UIScrollView
, such that the content is padded by the height of these bars.
The system keyboard is also designed to occlude the bottom half of the screen by default. In most cases, this is undesirable, so the app developer is expected to subscribe to NSNotificationCenter
keyboard events and adjust the UIScrollView
insets themselves.
WKWebView
automatically subscribes to th