How to hide the navigation bar and toolbar as scroll down? Swift (like myBridge app)

Question

I want to hide a toolbar and nav bar as I scroll down a page. And return it as I scroll up. How is this possible?

How would I go about detecting the drag? Do I use pan gesture or is this down with the scrollview?

Answer 1

Try this simple approach: Tested in Swift 3

    func scrollViewWillEndDragging(_ scrollView: UIScrollView, withVelocity velocity: CGPoint, targetContentOffset: UnsafeMutablePointer<CGPoint>) {

    if(velocity.y>0) {
        //Code will work without the animation block.I am using animation block incase if you want to set any delay to it.
        UIView.animate(withDuration: 2.5, delay: 0, options: UIViewAnimationOptions(), animations: { 
            self.navigationController?.setNavigationBarHidden(true, animated: true) 
            self.navigationController?.setToolbarHidden(true, animated: true)
            print("Hide")
        }, completion: nil)

    } else {
        UIView.animate(withDuration: 2.5, delay: 0, options: UIViewAnimationOptions(), animations: { 
            self.navigationController?.setNavigationBarHidden(false, animated: true)
            self.navigationController?.setToolbarHidden(false, animated: true)
            print("Unhide")
        }, completion: nil)    
      }
   }

Output: Updated

Note: If you passing any data from this VC to another VC that embedded with navigationController.You may need to unhide the NavigationBar.