I have an app (written in Objective C) that has a UI View that includes a UITableView and a UIToolbar. The bottom section of the table view is a UITextView.
Compiling with Xcode 9.0 and running on iPhone 6s (9.2) in the Simulator, tapping any of the buttons in the toolbar works fine, with the appropriate function being called.
Compiling with Xcode 9.0 and running on iPhone 6s (11.0) in the Simulator, tapping anywhere in the toolbar initiates editing in the text view. However, touching and holding on a button in the toolbar for about 3 seconds calls the associated button function.
iPad Air 2 behaves the same way,
My actual iPhone 6s running iOS 11.1 also has the same toolbar problem.
Compiling with Xcode 8.3.3 on a different Mac and running on my iPhone 6s
Under 9.2 and 11.0, the tapped toolbar button darkens as expected, but the results are quite different.