Change navigation bar bottom border color Swift

Question

It works with

import UIKit

class ViewController: UIViewController {

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup a         


        

Answer 1

Solution for Swift 4.0 - 5.2

Here is small extension for changing both Height and Color of bottom navbar line

extension UINavigationController
{
    func addCustomBottomLine(color:UIColor,height:Double)
    {
        //Hiding Default Line and Shadow
        navigationBar.setValue(true, forKey: "hidesShadow")
    
        //Creating New line
        let lineView = UIView(frame: CGRect(x: 0, y: 0, width:0, height: height))
        lineView.backgroundColor = color
        navigationBar.addSubview(lineView)
    
        lineView.translatesAutoresizingMaskIntoConstraints = false
        lineView.widthAnchor.constraint(equalTo: navigationBar.widthAnchor).isActive = true
        lineView.heightAnchor.constraint(equalToConstant: CGFloat(height)).isActive = true
        lineView.centerXAnchor.constraint(equalTo: navigationBar.centerXAnchor).isActive = true
        lineView.topAnchor.constraint(equalTo: navigationBar.bottomAnchor).isActive = true
    }
}

And after adding this extension, you can call this method on any UINavigationController (e.g. from ViewController viewDidLoad())

self.navigationController?.addCustomBottomLine(color: UIColor.black, height: 20)