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 after loading the view, typically from a nib.      self.navigationController?.navigationBar.setBackgroundImage(UIImage(), forBarMetrics: .Default)     self.navigationController?.navigationBar.shadowImage = UIColor.redColor().as1ptImage()   }  override func didReceiveMemoryWarning() {     super.didReceiveMemoryWarning()     // Dispose of any resources that can be recreated. }   }  extension UIColor {     func as1ptImage() -> UIImage {         UIGraphicsBeginImageContext(CGSizeMake(1, 1))         let ctx = UIGraphicsGetCurrentContext()         self.setFill()         CGContextFillRect(ctx, CGRect(x: 0, y: 0, width: 1, height: 1))         let image = UIGraphicsGetImageFromCurrentImageContext()         UIGraphicsEndImageContext()         return image     } } 

But when I add a UITableView it doesn't appear on it and when I add a UISearchView it appears but removes the navigation bar.

Anyone knows how to solve this?

Answer 1

You have to adjust the shadowImage property of the navigation bar.

Try this one. I created a category on UIColor as an helper, but you can refactor the way you prefer.

extension UIColor {     func as1ptImage() -> UIImage {         UIGraphicsBeginImageContext(CGSizeMake(1, 1))         let ctx = UIGraphicsGetCurrentContext()         self.setFill()         CGContextFillRect(ctx, CGRect(x: 0, y: 0, width: 1, height: 1))         let image = UIGraphicsGetImageFromCurrentImageContext()         UIGraphicsEndImageContext()         return image     } } 

Option 1: on a single navigation bar

And then in your view controller (change the UIColor to what you like):

// We can use a 1px image with the color we want for the shadow image self.navigationController?.navigationBar.shadowImage = UIColor.redColor().as1ptImage()  // We need to replace the navigation bar's background image as well  // in order to make the shadowImage appear. We use the same 1px color tecnique self.navigationController?.navigationBar.setBackgroundImage(UIColor.yellowColor‌​().as1ptImage(), forBarMetrics: .Default)     

Option 2: using appearance proxy, on all navigation bars

Instead of setting the background image and shadow image on each navigation bar, it is possible to rely on UIAppearance proxy. You could try to add those lines to your AppDelegate, instead of adding the previous ones in the viewDidLoad.

// We can use a 1px image with the color we want for the shadow image UINavigationBar.appearance().shadowImage = UIColor.redColor().as1ptImage()  // We need to replace the navigation bar's background image as well  // in order to make the shadowImage appear. We use the same 1px color technique UINavigationBar.appearance().setBackgroundImage(UIColor.yellowColor().as1ptImage(), forBarMetrics: .Default) 

Answer 2

Wonderful contributions from @TheoF, @Alessandro and @Pavel.

Here is what I did for...

Swift 4

extension UIColor {      /// Converts this `UIColor` instance to a 1x1 `UIImage` instance and returns it.     ///     /// - Returns: `self` as a 1x1 `UIImage`.     func as1ptImage() -> UIImage {         UIGraphicsBeginImageContext(CGSize(width: 1, height: 1))         setFill()         UIGraphicsGetCurrentContext()?.fill(CGRect(x: 0, y: 0, width: 1, height: 1))         let image = UIGraphicsGetImageFromCurrentImageContext() ?? UIImage()         UIGraphicsEndImageContext()         return image     } } 

Using it in viewDidLoad():

/* In this example, I have a ViewController embedded in a NavigationController in IB. */  // Remove the background color. navigationController?.navigationBar.setBackgroundImage(UIColor.clear.as1ptImage(), for: .default)  // Set the shadow color. navigationController?.navigationBar.shadowImage = UIColor.gray.as1ptImage()