问题
i've been trying to remove the navigationBars border without luck. I've researched and people seem to tell to set shadowImage and BackgroundImage to nil, but this does not work in my case.
My code
self.navigationController?.navigationBar.barTintColor = UIColor(rgba: "#4a5866")
self.navigationController?.navigationBar.setBackgroundImage(UIImage(named: ""), forBarMetrics: UIBarMetrics.Default)
self.navigationController?.navigationBar.shadowImage = UIImage(named: "")
illustration:
回答1:
The trouble is with these two lines:
self.navigationController?.navigationBar.setBackgroundImage(UIImage(named: ""), forBarMetrics: UIBarMetrics.Default)
self.navigationController?.navigationBar.shadowImage = UIImage(named: "")
Since you don't have an image with no name, UIImage(named: "") returns nil, which means the default behavior kicks in:
When non-nil, a custom shadow image to show instead of the default shadow image. For a custom shadow to be shown, a custom background image must also be set with -setBackgroundImage:forBarMetrics: (if the default background image is used, the default shadow image will be used).
You need a truly empty image, so just initialize with UIImage():
self.navigationController?.navigationBar.setBackgroundImage(UIImage(), for: UIBarMetrics.default)
self.navigationController?.navigationBar.shadowImage = UIImage()
回答2:
this will remove the shadow image altogether
for parent in self.navigationController!.navigationBar.subviews {
for childView in parent.subviews {
if(childView is UIImageView) {
childView.removeFromSuperview()
}
}
}
回答3:
With Swift 2 you can do it this way:
AppDelegate file
Inside func application(..., didFinishLaunchingWithOptions launchOptions:...)
UINavigationBar.appearance().shadowImage = UIImage()
UINavigationBar.appearance().setBackgroundImage(UIImage(), forBarMetrics: .Default)
for Swift 3:
UINavigationBar.appearance().shadowImage = UIImage()
UINavigationBar.appearance().setBackgroundImage(UIImage(), for: .default)
回答4:
Swift 4 & Swift 5
Removing border:
self.navigationController?.navigationBar.setBackgroundImage(UIImage(), for:.default)
self.navigationController?.navigationBar.shadowImage = UIImage()
self.navigationController?.navigationBar.layoutIfNeeded()
Restoring border:
self.navigationController?.navigationBar.setBackgroundImage(nil, for:.default)
self.navigationController?.navigationBar.shadowImage = nil
self.navigationController?.navigationBar.layoutIfNeeded()
回答5:
Just write this in the extension of UINavigationBar
extension UINavigationBar {
func shouldRemoveShadow(_ value: Bool) -> Void {
if value {
self.setValue(true, forKey: "hidesShadow")
} else {
self.setValue(false, forKey: "hidesShadow")
}
}
}
And in your viewController...
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
self.navigationController?.navigationBar.shouldRemoveShadow(true)
}
And to get this undone for any viewController, just pass false.
回答6:
Set barStyle to .Black before setting the tint:
self.navigationController?.navigationBar.translucent = false
self.navigationController?.navigationBar.barStyle = .Black
self.navigationController?.navigationBar.barTintColor = UIColor.blueColor()
回答7:
Luca Davanzo's answer is great, but it does not work in iOS 10. I altered it to work in iOS 10 and below.
for parent in navigationController!.view.subviews {
for child in parent.subviews {
for view in child.subviews {
if view is UIImageView && view.frame.height == 0.5 {
view.alpha = 0
}
}
}
}
You can also extend UINavigationController and call this off of that. removeFromSuperview() on the line will not work on iOS 10, so I just set the alpha to 0 so this one call is compatible everywhere.
回答8:
To remove border from UINavigationBar in Swift 3+, use:
UINavigationBar.appearance().shadowImage = UIImage()
UINavigationBar.appearance().setBackgroundImage(UIImage(), for: .default)
UINavigationBar.appearance().isTranslucent = false
回答9:
for swift 3
in viewDidLoad method
navigationController?.navigationBar.setBackgroundImage(UIImage(), for: .default)
navigationController?.navigationBar.shadowImage = UIImage()
回答10:
Updated for Swift 4 in case someone is wondering
navigationBar.shadowImage = UIImage()
navigationBar.backIndicatorImage = UIImage()
It's even less verbose now.
回答11:
Only this worked for me,
self.navigationController?.navigationBar.shadowImage = UIImage()
Ref
回答12:
This is the way if you want to do it without changing the background color:
// Remove the border ImageView from the NavigationBar background
func hideBottomBorder() {
for view in navigationBar.subviews.filter({ NSStringFromClass($0.dynamicType) == "_UINavigationBarBackground" }) as [UIView] {
if let imageView = view.subviews.filter({ $0 is UIImageView }).first as? UIImageView {
imageView.removeFromSuperview()
}
}
}
NOTE: This might crash on a production app. Apparently the NavigationBar doesn't like its view disappearing
回答13:
The accepted answer worked for me but I noticed when I wanted the shadow image to reappear when popping back or pushing forward to another vc there was a noticeable blink in the navigation bar.
Using this method navigationController?.navigationBar.setValue(true, forKey: "hidesShadow")
in viewWillAppear the shadow bar is hidden in the current visible view controller.
Using these 2 methods
navigationController?.navigationBar.setBackgroundImage(nil, for: .default)
navigationController?.navigationBar.setValue(false, forKey: "hidesShadow")
in viewWillDisappear the blink still happens but only when the shadow image reappears and not the navigation bar itself.
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
// 1. hide the shadow image in the current view controller you want it hidden in
navigationController?.navigationBar.setValue(true, forKey: "hidesShadow")
navigationController?.navigationBar.layoutIfNeeded()
}
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(true)
// 2. show the shadow image when pushing or popping in the next view controller. Only the shadow image will blink
navigationController?.navigationBar.setBackgroundImage(nil, for: .default)
navigationController?.navigationBar.setValue(false, forKey: "hidesShadow")
navigationController?.navigationBar.layoutIfNeeded()
}
回答14:
for the swift3 you should write slightly different way:
self.navigationController?.navigationBar.setBackgroundImage(UIImage(),
for: UIBarMetrics.default)
self.navigationController?.navigationBar.shadowImage = UIImage()
回答15:
This is a streamlined version of Gaurav Chandarana's answer.
extension UINavigationBar {
func hideShadow(_ value: Bool = true) {
setValue(value, forKey: "hidesShadow")
}
}
回答16:
If you want to remove only the bottom line and keep the solid color of navigationBar, add these lines of code in viewDidLoad: Swift 3, 4:
navigationController?.navigationBar.shadowImage = UIImage()
navigationController?.navigationBar.isTranslucent = false
Peace!
回答17:
Swift 5
When using setBackgroundImage / shadowImage to hide the hairline, there's a slight delay. This method removes the delay. Credit to Chameleon Framework. This is the method they use (in ObjC)
extension UINavigationController {
func hideHairline() {
if let hairline = findHairlineImageViewUnder(navigationBar) {
hairline.isHidden = true
}
}
func restoreHairline() {
if let hairline = findHairlineImageViewUnder(navigationBar) {
hairline.isHidden = false
}
}
func findHairlineImageViewUnder(_ view: UIView) -> UIImageView? {
if view is UIImageView && view.bounds.size.height <= 1.0 {
return view as? UIImageView
}
for subview in view.subviews {
if let imageView = self.findHairlineImageViewUnder(subview) {
return imageView
}
}
return nil
}
}
回答18:
The border line is an UIImageView and removing a subview which is an imageView will remove barButtonItems with UIImageView. Below code will help you remove it. Hope this helps someone who faced an issue like me.
for parent in self.navigationController!.navigationBar.subviews {
for childView in parent.subviews {
if childView.frame.height == 0.5 {
childView.removeFromSuperview()
}
}
}
The border UIImageView is only 0.5 in height so this code removes only that.
回答19:
Within AppDelegate, this has globally changed the format of the NavBar and removes the bottom line/border:
func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
UINavigationBar.appearance().setBackgroundImage(UIImage(), forBarPosition: UIBarPosition.Any, barMetrics: UIBarMetrics.Default)
UINavigationBar.appearance().shadowImage = UIImage()
UINavigationBar.appearance().tintColor = UIColor.whiteColor()
UINavigationBar.appearance().barTintColor = UIColor.redColor()
UINavigationBar.appearance().translucent = false
UINavigationBar.appearance().clipsToBounds = false
//UINavigationBar.appearance().backgroundColor = UIColor.redColor()
UINavigationBar.appearance().titleTextAttributes = [NSFontAttributeName : (UIFont(name: "FONT NAME", size: 18))!, NSForegroundColorAttributeName: UIColor.whiteColor()] }
Haven't managed to implement anything different on a specific VC, but this will help 90% of people
回答20:
this is the answer in swift 3 base of Nate Cook answer
self.navigationController?.navigationBar.setBackgroundImage(UIImage(), for: UIBarMetrics.default)
self.navigationController?.navigationBar.shadowImage = UIImage()
回答21:
iOS 11 and Swift 4 You should try following if you want to remove the border but don't to make the navigitonbar translucent
self.navigationBar.shadowImage = UIImage()
回答22:
App delegate
UINavigationBar.appearance().setBackgroundImage(UIImage(), for: UIBarMetrics.default)
UINavigationBar.appearance().shadowImage = UIImage()
回答23:
in your custom navigationController add these lines:
self.navigationBar.setBackgroundImage(UIImage(), for:.default)
self.navigationBar.shadowImage = UIImage()
self.navigationBar.layoutIfNeeded()
Important Note
the last line is important if you use the first line viewDidLoad() method because navigationController should redraw nav bar but easily you can use this without layoutIfNeeded() in the viewWillAppear() method before it draws the nav bar
来源：https://stackoverflow.com/questions/26390072/remove-border-in-navigationbar-in-swift