transparent navigation bar ios

问题

I\'m creating an app and i\'ve browsed on the internet and i\'m wondering how they make this transparent navigationBar like this:

I\'ve added following like in my appdelegate:

UINavigationBar.appearance().translucent = true

but this just makes it look like following:

How can i make the navigationBar transparent like first image

回答1:

You can apply Navigation Bar Image like below for Translucent.

Objective-C:

[self.navigationController.navigationBar setBackgroundImage:[UIImage new]
                     forBarMetrics:UIBarMetricsDefault]; //UIImageNamed:@"transparent.png"
self.navigationController.navigationBar.shadowImage = [UIImage new];////UIImageNamed:@"transparent.png"
self.navigationController.navigationBar.translucent = YES;
self.navigationController.view.backgroundColor = [UIColor clearColor];

Swift 3:

self.navigationController?.navigationBar.setBackgroundImage(UIImage(), for: .default)
self.navigationController?.navigationBar.shadowImage = UIImage()
self.navigationController?.navigationBar.isTranslucent = true
self.navigationController?.view.backgroundColor = .clear

Hope it helps you..!

回答2:

Swift Solution

This is the best way that I've found. You can just paste it into your appDelegate's didFinishLaunchingWithOptions method:

Swift 3 / 4

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
    // Override point for customization after application launch.
    // Sets background to a blank/empty image
    UINavigationBar.appearance().setBackgroundImage(UIImage(), for: .default)
    // Sets shadow (line below the bar) to a blank image
    UINavigationBar.appearance().shadowImage = UIImage()
    // Sets the translucent background color
    UINavigationBar.appearance().backgroundColor = .clear
    // Set translucent. (Default value is already true, so this can be removed if desired.)
    UINavigationBar.appearance().isTranslucent = true
    return true
}

Swift 2.0

func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
    // Override point for customization after application launch.
    // Sets background to a blank/empty image
    UINavigationBar.appearance().setBackgroundImage(UIImage(), forBarMetrics: .Default)
    // Sets shadow (line below the bar) to a blank image
    UINavigationBar.appearance().shadowImage = UIImage()
    // Sets the translucent background color
    UINavigationBar.appearance().backgroundColor = UIColor(red: 0.0, green: 0.0, blue: 0.0, alpha: 0.0)
    // Set translucent. (Default value is already true, so this can be removed if desired.)
    UINavigationBar.appearance().translucent = true

    return true
}

source: Make navigation bar transparent regarding below image in iOS 8.1

回答3:

Swift 3 : extension for Transparent Navigation Bar

extension UINavigationBar {
    func transparentNavigationBar() {
    self.setBackgroundImage(UIImage(), for: .default)
    self.shadowImage = UIImage()
    self.isTranslucent = true
    }
}

回答4:

Swift 4.2 Solution: For transparent Background:

For General Approach:

override func viewDidLoad() {
    super.viewDidLoad()

    self.navigationController?.navigationBar.setBackgroundImage(UIImage(), for: UIBarMetrics.default)
    self.navigationController?.navigationBar.shadowImage = UIImage()
    self.navigationController?.navigationBar.isTranslucent = true

}

For Specific Object:

override func viewDidLoad() {
    super.viewDidLoad()

    navBar.setBackgroundImage(UIImage(), for: UIBarMetrics.default)
    navBar.shadowImage = UIImage()
    navBar.navigationBar.isTranslucent = true

}

Hope it's useful.

回答5:

I was able to accomplish this in swift this way:

let navBarAppearance = UINavigationBar.appearance()
let colorImage = UIImage.imageFromColor(UIColor.morselPink(), frame: CGRectMake(0, 0, 340, 64))
navBarAppearance.setBackgroundImage(colorImage, forBarMetrics: .Default)

where i created the following utility method in a UIColor category:

imageFromColor(color: UIColor, frame: CGRect) -> UIImage {
  UIGraphicsBeginImageContextWithOptions(frame.size, false, 0)
  color.setFill()
  UIRectFill(frame)
  let image = UIGraphicsGetImageFromCurrentImageContext()
  UIGraphicsEndImageContext()
  return image
}

回答6:

What it worked for me:

    let bar:UINavigationBar! =  self.navigationController?.navigationBar
    self.title = "Whatever..."
    bar.setBackgroundImage(UIImage(), forBarMetrics: UIBarMetrics.Default)
    bar.shadowImage = UIImage()
    bar.alpha = 0.0

回答7:

Swift 5 applying only to the current view controller

override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)

    // Make the navigation bar background clear
    navigationController?.navigationBar.setBackgroundImage(UIImage(), for: .default)
    navigationController?.navigationBar.shadowImage = UIImage()
    navigationController?.navigationBar.isTranslucent = true
}

override func viewWillDisappear(_ animated: Bool) {
    super.viewWillDisappear(animated)

    // Restore the navigation bar to default
    navigationController?.navigationBar.setBackgroundImage(nil, for: .default)
    navigationController?.navigationBar.shadowImage = nil
}

回答8:

Set the background property of your navigationBar, e.g.

navigationController?.navigationBar.backgroundColor = UIColor(red: 1.0, green: 0.0, blue: 0.0, alpha: 0.5)

(You may have to change that a bit if you don't have a navigation controller, but that should give you an idea of what to do.)

Also make sure that the view below actually extends under the bar.

回答9:

Try this, it works for me if you also need to support ios7, it is based on the transparency of UItoolBar:

[self.navigationController.navigationBar setBackgroundImage:[UIImage new]
                                                  forBarMetrics:UIBarMetricsDefault];
    self.navigationController.navigationBar.shadowImage = [UIImage new];
    self.navigationController.navigationBar.translucent = YES;
    self.navigationController.view.backgroundColor = [UIColor clearColor];
    UIToolbar* blurredView = [[UIToolbar alloc] initWithFrame:self.navigationController.navigationBar.bounds];
    [blurredView setBarStyle:UIBarStyleBlack];
    [blurredView setBarTintColor:[UIColor redColor]];
    [self.navigationController.navigationBar insertSubview:blurredView atIndex:0];

回答10:

If you want to be able to do this programmatically in swift 4 while staying on the same view,

if change {
        navigationController?.navigationBar.isTranslucent = false
        self.navigationController?.navigationBar.backgroundColor = UIColor(displayP3Red: 255/255, green: 206/255, blue: 24/255, alpha: 1)
        navigationController?.navigationBar.barTintColor = UIColor(displayP3Red: 255/255, green: 206/255, blue: 24/255, alpha: 1)
    } else {
        navigationController?.navigationBar.isTranslucent = true
        navigationController?.navigationBar.setBackgroundImage(backgroundImage, for: .default)
        navigationController?.navigationBar.backgroundColor = .clear
        navigationController?.navigationBar.barTintColor = .clear
    }

One important thing to remember though is to click this button in your storyboard. I had an issue with a jumping display for a long time. Make sureyou set this:

Then when you change the translucency of the navigation bar it will not cause the views to jump as the views extend all the way to the top, regardless of the visiblity of the navigation bar.

回答11:

Utility method which you call by passing navigationController and color which you like to set on navigation bar. For transparent you can use clearColor of UIColor class.

For objective c -

+ (void)setNavigationBarColor:(UINavigationController *)navigationController 
                               color:(UIColor*) color {
   [navigationController setNavigationBarHidden:false animated:false];
   [navigationController.navigationBar setBackgroundImage:[UIImage new] forBarMetrics:UIBarMetricsDefault];
   [navigationController.navigationBar setShadowImage:[UIImage new]];
   [navigationController.navigationBar setTranslucent:true];
   [navigationController.view setBackgroundColor:color];
   [navigationController.navigationBar setBackgroundColor:color];
}

For Swift 3.0 -

class func setNavigationBarColor(navigationController : UINavigationController?, 
                                 color : UIColor) {
    navigationController?.setNavigationBarHidden(false, animated: false)
    navigationController?.navigationBar .setBackgroundImage(UIImage(), forBarMetrics: UIBarMetrics.Default)
    navigationController?.navigationBar.shadowImage = UIImage()
    navigationController?.navigationBar.translucent = true
    navigationController?.view.backgroundColor = color
    navigationController?.navigationBar.backgroundColor =  color
}

回答12:

For those looking for OBJC solution, to be added in App Delegate didFinishLaunchingWithOptions method:

[[UINavigationBar appearance] setBackgroundImage:[UIImage new] forBarMetrics:UIBarMetricsDefault];
[UINavigationBar appearance].shadowImage = [UIImage new];
[UINavigationBar appearance].backgroundColor = [UIColor clearColor];
[UINavigationBar appearance].translucent = YES;

回答13:

Add this in your did load

self.navigationController?.navigationBar.setBackgroundImage(UIImage(), for: .default)
self.navigationController?.navigationBar.shadowImage = UIImage()
self.navigationController?.navigationBar.backgroundColor = UIColor(red: 1, green: 1, blue: 1, alpha: 0.0)
//adjust alpha according to your need 0 is transparent 1 is solid

来源：https://stackoverflow.com/questions/25845855/transparent-navigation-bar-ios

标签

ios

iphone

swift

uinavigationbar