setNavigationBarHidden not working - ios

Question

this may seem obvious to some of you but I can't find an answer anywhere online. I am trying to make my Navigation Bar only appear on one View Controller so as all the tutorials show I just added this:
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
self.navigationController?.setNavigationBarHidden(true, animated: false)
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
self.navigationController?.setNavigationBarHidden(false, animated: false)
}
But when I exit out of this View Controller and then return to it, the Nav Bar isnt there. Any ideas??

Answer 1

I think you're on the right track however you need to define the action taken. Let's say you have UIScrollView in the View Controller and you want the navigation bar to disappear so here's the code the best you can use.
func scrollViewWillEndDragging(_ scrollView: UIScrollView, withVelocity velocity: CGPoint, targetContentOffset: UnsafeMutablePointer<CGPoint>) {
if(velocity.y>0) {
UIView.animate(withDuration: 2.5, delay: 0, options: UIViewAnimationOptions(), animations: {
self.navigationController?.setNavigationBarHidden(true, animated: true)
}, completion: nil)
} else {
UIView.animate(withDuration: 2.5, delay: 0, options: UIViewAnimationOptions(), animations: {
self.navigationController?.setNavigationBarHidden(false, animated: true)
}, completion: nil)
}
}
In your case you don't need to declare the animation twice it's already defined by the function try removing that as following.
override func viewWillDisappear(_ animated: Bool) {
self.navigationController?.setNavigationBarHidden(true, animated: false)
}
override func viewWillAppear(_ animated: Bool) {
self.navigationController?.setNavigationBarHidden(false, animated: false)
}