更改导航栏底部边框颜色Swift

It works with

它适用于

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
    }
}
import UIKit

class Vie