In designing a viewcontroller i've hidden the navigation bar for full app, and added a custom view in each viewcontroller above tableview looks like navigationbar. but it is not visible when running app. below are the screenshots of storyboard and running image. In full app i have used same approach working perfectly but not working in two viewcontrollers only. This problem arises when iOS 12 is introduced before that working perfect in iOS 10. currently using Xcode 9.2 for that project.
Check your View Hierarchy in Storyboard where you placed objects (UITableView, UIView, UIButton ...). keep your View in bottom of all the view objects which you want to be on Top.