navigation bar back ground color will change into wrong color when table view scrolls in swift 4

Question

I seen this video on you tube https://www.youtube.com/watch?v=rNy6aQQYbuY But the problem is that navigation bar color will not change color into correct color that I want to be

so here is the codes

override func viewDidLoad() {
    super.viewDidLoad()
    self.navigationController?.navigationBar.isTranslucent = true
    self.navigationController?.navigationBar.tintColor = .white
    if #available(iOS 11.0, *) {
        self.profileTV.contentInsetAdjustmentBehavior = .never
    } else {
        automaticallyAdjustsScrollViewInsets = false
    }
    self.navigationController?.navigationBar.setBackgroundImage(UIImage(), for: .default)

    self.navigationController?.navigationBar.shadowImage = UIImage()
}

func scrollViewDidScroll(_ scrollView: UIScrollView) {
     print(scrollView.contentOffset.y)
    var offset = scrollView.contentOffset.y / 150
    if offset > 1 {
        offset = 1
        let color = UIColor(red: 181, green: 40, blue: 56, alpha: offset)
        self.navigationController?.navigationBar.backgroundColor = color
        UIApplication.shared.statusBarView?.backgroundColor = color
    } else {
        let color = UIColor(red: 181, green: 40, blue: 56, alpha: offset)
        self.navigationController?.navigationBar.backgroundColor = color
        UIApplication.shared.statusBarView?.backgroundColor = color
    }
}


extension UIApplication {
  var statusBarView: UIView? {
      return value(forKey: "statusBar") as? UIView
  }
}

the color after scrolling will be white But I want to be the color code that I wrote in my codes

Answer 1

change your code to:

func setNavigation() {
    if #available(iOS 11.0, *) {
        self.tV.contentInsetAdjustmentBehavior = .never
    } else {
        automaticallyAdjustsScrollViewInsets = false
    }
    self.navigationController?.navigationBar.tintColor = .red
    self.navigationController?.navigationBar.isTranslucent = true


    self.navigationController?.navigationBar.setBackgroundImage(UIImage(), for: .default)

    self.navigationController?.navigationBar.shadowImage = UIImage()

}


func scrollViewDidScroll(_ scrollView: UIScrollView) {

    var offset = scrollView.contentOffset.y / 1500


    if offset >= 1 {
        offset = 1
        self.navigationController?.navigationBar.backgroundColor = UIColor.white.withAlphaComponent(offset)
      //  self.navigationController?.navigationBar.alpha = offset
      //  print(offset - 0.399)
        UIApplication.shared.statusBarView?.backgroundColor = UIColor.red.withAlphaComponent(offset)
    } else {
        self.navigationController?.navigationBar.backgroundColor = UIColor.white.withAlphaComponent(offset)
        UIApplication.shared.statusBarView?.backgroundColor = UIColor.red.withAlphaComponent(offset)
    }
}