You need to add this code in your AppDelegate file, not in your Root View Controller
Or add the property Status bar is initially hidden in your plist file
Folks, in iOS 7+
please add this to your info.plist file, It will make the difference :)
UIStatusBarHidden UIViewControllerBasedStatusBarAppearance
For iOS 11.4+ and Xcode 9.4 +
Use this code either in one or all your view controllers
override var prefersStatusBarHidden: Bool { return true }