How to hide a navigation bar from first ViewController in Swift?

If you know that all other views should have the bar visible, you could use viewWillDisappear to set it to visible again.

In Swift:

override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)
    navigationController?.setNavigationBarHidden(true, animated: animated)
}

override func viewWillDisappear(_ animated: Bool) {
    super.viewWillDisappear(animated)
    navigationController?.setNavigationBarHidden(false, animated: animated)
}

Swift 3

override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)

    // Hide the navigation bar on the this view controller
    self.navigationController?.setNavigationBarHidden(true, animated: animated)
}

override func viewWillDisappear(_ animated: Bool) {
    super.viewWillDisappear(animated)

    // Show the navigation bar on other view controllers
    self.navigationController?.setNavigationBarHidden(false, animated: animated)
}

You can unhide navigationController in viewWillDisappear

override func viewWillDisappear(animated: Bool)
{
    super.viewWillDisappear(animated)
    self.navigationController?.isNavigationBarHidden = false
}

Swift 3

override func viewWillDisappear(_ animated: Bool) {
    super.viewWillDisappear(animated)

    self.navigationController?.setNavigationBarHidden(false, animated: animated)
}

You could also create an extension for this so you will be able to reuse the extension without implementing this again and again in every view controller.

import UIKit

extension UIViewController {
    func hideNavigationBar(animated: Bool){
        // Hide the navigation bar on the this view controller
        self.navigationController?.setNavigationBarHidden(true, animated: animated)

    }

    func showNavigationBar(animated: Bool) {
        // Show the navigation bar on other view controllers
        self.navigationController?.setNavigationBarHidden(false, animated: animated)
    }

}

So you can use the extension methods as below

    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        hideNavigationBar(animated: animated)
    }

    override func viewWillDisappear(_ animated: Bool) {
        super.viewWillDisappear(animated)
        showNavigationBar(animated: animated)
    }

In Swift 3, you can use isNavigationBarHidden Property also to show or hide navigation bar

override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)
    // Hide the navigation bar for current view controller
    self.navigationController?.isNavigationBarHidden = true;
}

override func viewWillDisappear(_ animated: Bool) {
    super.viewWillDisappear(animated)
    // Show the navigation bar on other view controllers
   self.navigationController?.isNavigationBarHidden = false;
}