如何隐藏UINavigationBar 1px底线

Question

我有一个应用程序,有时需要其导航栏与内容融为一体.

有谁知道如何摆脱或改变这个讨厌的小酒吧的颜色？

在下面的图像我有 - 我正在谈论"根视图控制器"下面这个1px高度线

Answer 1

为此,您应该设置自定义阴影图像.但是要显示阴影图像,您还需要设置自定义背景图像,引用Apple的文档:

要显示自定义阴影图像,还必须使用setBackgroundImage(_:for :)方法设置自定义背景图像.如果使用默认背景图像,则无论此属性的值如何,都将使用默认阴影图像.

所以:

let navigationBar = navigationController!.navigationBar
navigationBar.setBackgroundImage(#imageLiteral(resourceName: "BarBackground"),
                                                        for: .default)
navigationBar.shadowImage = UIImage()

以上是隐藏它的唯一"官方"方式.不幸的是,它消除了酒吧的半透明度.

我不想要背景图片,只需要颜色

你有这些选择:

1. 纯色,无透明度:

   navigationBar.barTintColor = UIColor.redColor()
   navigationBar.isTranslucent = false
   navigationBar.setBackgroundImage(UIImage(), for: .default)
   navigationBar.shadowImage = UIImage()
   

2. 创建填充颜色的小背景图像并使用它.

3. 使用下面描述的'hacky'方法.它还会保持酒吧半透明.

如何保持酒吧半透明？

为了保持半透明,你需要另一种方法,它看起来像一个黑客,但运作良好.我们试图删除的阴影是在.shadowColor某处的发际线UIImageView.我们可以找到它并在需要时隐藏/显示它.

下面的说明假设您只需要在UINavigationBar层次结构的一个控制器中隐藏发际线.

1. 声明实例变量:

   private var shadowImageView: UIImageView?
   

2. 添加找到这个阴影的方法(发际线) UINavigationController

   private func findShadowImage(under view: UIView) -> UIImageView? {
       if view is UIImageView && view.bounds.size.height <= 1 {
           return (view as! UIImageView)
       }
   
       for subview in view.subviews {
           if let imageView = findShadowImage(under: subview) {
               return imageView
           }
       }
       return nil
   }
   

3. 添加/编辑UIImageView:方法:

   override func viewWillAppear(_ animated: Bool) {
       super.viewWillAppear(animated)
   
       if shadowImageView == nil {
           shadowImageView = findShadowImage(under: navigationController!.navigationBar)
       }
       shadowImageView?.isHidden = true
   }
   
   override func viewWillDisappear(_ animated: Bool) {
       super.viewWillDisappear(animated)
   
       shadowImageView?.isHidden = false
   }
   

相同的方法也适用于viewWillAppear/viewWillDisappear发际线,(几乎)你需要隐藏的任何其他东西:)

非常感谢@Leo Natan最初的想法!

Answer 2

以下可以帮助简单!

迅速:

self.navigationController?.navigationBar.setValue(true, forKey: "hidesShadow")

目标C:

[self.navigationController.navigationBar setValue:@(YES) forKeyPath:@"hidesShadow"];

Answer 3

如果您只想使用实心导航栏颜色并在故事板中进行设置,请在AppDelegate班级中使用此代码通过外观代理删除1像素边框:

[[UINavigationBar appearance] setBackgroundImage:[[UIImage alloc] init]
                                  forBarPosition:UIBarPositionAny
                                      barMetrics:UIBarMetricsDefault];

[[UINavigationBar appearance] setShadowImage:[[UIImage alloc] init]];

Answer 4

试试这个:

[[UINavigationBar appearance] setBackgroundImage: [UIImage new]  
                                   forBarMetrics: UIBarMetricsDefault];

[UINavigationBar appearance].shadowImage = [UIImage new];

下面的图片有解释(iOS7 NavigationBar):

并检查这个问题: iOS7 - 更改UINavigationBar边框颜色

Answer 5

想要添加Swift版本的Serhii的答案.我创建了UIBarExtension.swift以下内容:

import Foundation
import UIKit

extension UINavigationBar {
    func hideBottomHairline() {
        self.hairlineImageView?.isHidden = true
    }

    func showBottomHairline() {
        self.hairlineImageView?.isHidden = false
    }
}

extension UIToolbar {
    func hideBottomHairline() {
        self.hairlineImageView?.isHidden = true
    }

    func showBottomHairline() {
        self.hairlineImageView?.isHidden = false
    }
}

extension UIView {
    fileprivate var hairlineImageView: UIImageView? {
        return hairlineImageView(in: self)
    }

    fileprivate func hairlineImageView(in view: UIView) -> UIImageView? {
        if let imageView = view as? UIImageView, imageView.bounds.height <= 1.0 {
            return imageView
        }

        for subview in view.subviews {
            if let imageView = self.hairlineImageView(in: subview) { return imageView }
        }

        return nil
    }
}

Answer 6

快速做到这一点:

UINavigationBar.appearance().setBackgroundImage(
    UIImage(),
    forBarPosition: .Any,
    barMetrics: .Default)

UINavigationBar.appearance().shadowImage = UIImage()

Answer 7

快速简单的解决方案

   let navigationBar = self.navigationController?.navigationBar
    navigationBar?.setBackgroundImage(UIImage(), forBarPosition: UIBarPosition.Any, barMetrics: UIBarMetrics.Default)
    navigationBar?.shadowImage = UIImage()

Answer 8

在研究了Serhil的答案后,我创建了一个可以轻松隐藏发际线的吊舱UINavigationBar + Addition.

#import "UINavigationBar+Addition.h"

- (void)viewDidLoad {
    [super viewDidLoad];

    UINavigationBar *navigationBar = self.navigationController.navigationBar;
    [navigationBar hideBottomHairline];
}

Answer 9

在Swift 3.0中

AppDelegate.swift通过将以下代码添加到应用程序功能来编辑您的:

// Override point for customization after application launch.

// Remove border in navigationBar
UINavigationBar.appearance().shadowImage = UIImage()
UINavigationBar.appearance().setBackgroundImage(UIImage(), for: .default)

Answer 10

针对Swift 2.0更新了pxpgraphics的解决方案

extension UINavigationBar {

    func hideBottomHairline()
    {
        hairlineImageViewInNavigationBar(self)?.hidden = true
    }

    func showBottomHairline()
    {
        hairlineImageViewInNavigationBar(self)?.hidden = false
    }

    private func hairlineImageViewInNavigationBar(view: UIView) -> UIImageView?
    {
        if let imageView = view as? UIImageView where imageView.bounds.height <= 1
        {
            return imageView
        }

        for subview: UIView in view.subviews
        {
            if let imageView = hairlineImageViewInNavigationBar(subview)
            {
                return imageView
            }
        }

        return nil
    }

}

extension UIToolbar
{

    func hideHairline()
    {
        let navigationBarImageView = hairlineImageViewInToolbar(self)?.hidden = true
    }

    func showHairline()
    {
        let navigationBarImageView = hairlineImageViewInToolbar(self)?.hidden = false
    }

    private func hairlineImageViewInToolbar(view: UIView) -> UIImageView?
    {
        if let imageView = view as? UIImageView where imageView.bounds.height <= 1
        {
            return imageView
        }

        for subview: UIView in view.subviews
        {
            if let imageView = hairlineImageViewInToolbar(subview)
            {
                return imageView
            }
        }

        return nil
    }

}

Answer 11

Swift 4 //用于隐藏导航栏阴影线

navigationController?.navigationBar.shadowImage = UIImage()

Answer 12

也可以从情节提要中隐藏（在Xcode 10.1上使用）

通过添加运行时属性：hidesShadow-布尔值-True

Answer 13

从iOS 13开始，有一个系统API可以设置或删除阴影

UIKit使用shadowImage和shadowColor属性确定阴影的外观。当shadowImage为nil时，该条显示根据shadowColor属性中的值着色的默认阴影。如果shadowColor为nil或包含clearColor颜色，则该条不显示阴影。

    let appearance = UINavigationBarAppearance()
    appearance.shadowImage = nil
    appearance.shadowColor = nil
    navigationController.navigationBar.standardAppearance = appearance

Answer 14

我使用UINavigationBar扩展,使我能够使用UIAppearance API隐藏/显示阴影,或选择使用Storyboard(或源代码)隐藏/显示阴影的导航栏.这是扩展名:

import UIKit

private var flatAssociatedObjectKey: UInt8 = 0

/*
  An extension that adds a "flat" field to UINavigationBar. This flag, when
  enabled, removes the shadow under the navigation bar.
 */
@IBDesignable extension UINavigationBar {
    @IBInspectable var flat: Bool {
        get {
            guard let obj = objc_getAssociatedObject(self, &flatAssociatedObjectKey) as? NSNumber else {
                return false
            }
            return obj.boolValue;
        }

        set {
            if (newValue) {
                let void = UIImage()
                setBackgroundImage(void, forBarPosition: .Any, barMetrics: .Default)
                shadowImage = void
            } else {
                setBackgroundImage(nil, forBarPosition: .Any, barMetrics: .Default)
                shadowImage = nil
            }
            objc_setAssociatedObject(self, &flatAssociatedObjectKey, NSNumber(bool: newValue),
                    objc_AssociationPolicy.OBJC_ASSOCIATION_RETAIN_NONATOMIC)
        }
    }
}

现在,要禁用所有导航栏上的阴影,您必须使用:

UINavigationBar.appearance().flat = true

或者您可以使用故事板启用/禁用此行为:

Answer 15

适用于 iOS 13+

诀窍是用'UINavigationBarAppearance'初始化TransparentBackground。然后您可以轻松删除导航栏的水平线。

let appearance = UINavigationBarAppearance()
appearance.configureWithTransparentBackground()
appearance.backgroundColor = .green // Required background color

最后，按照苹果的建议将外观更改添加到导航项。

self.navigationItem.standardAppearance = appearance
self.navigationItem.scrollEdgeAppearance = appearance
self.navigationItem.compactAppearance = appearance

Answer 16

Swift 4测试了 一线解决方案

在Viewdidload() 设置导航控制器的用户默认值true为键"hidesShadow"

override func viewDidLoad() {
    super.viewDidLoad()

    self.navigationController?.navigationBar.setValue(true, forKey: "hidesShadow")

}

Answer 17

如果您想保留半透明度并且不想UINavigationController在应用程序中创建每个子类,则另一个选项是:

#import <objc/runtime.h>

@implementation UINavigationController (NoShadow)

+ (void)load {
    Method original = class_getInstanceMethod(self, @selector(viewWillAppear:));
    Method swizzled = class_getInstanceMethod(self, @selector(swizzled_viewWillAppear:));
    method_exchangeImplementations(original, swizzled);
}

+ (UIImageView *)findHairlineImageViewUnder:(UIView *)view {
    if ([view isKindOfClass:UIImageView.class] && view.bounds.size.height <= 1.0) {
        return (UIImageView *)view;
    }

    for (UIView *subview in view.subviews) {
        UIImageView *imageView = [self findHairlineImageViewUnder:subview];
        if (imageView) {
            return imageView;
        }
    }

    return nil;
}

- (void)swizzled_viewWillAppear:(BOOL)animated {
    UIImageView *shadow = [UINavigationController findHairlineImageViewUnder:self.navigationBar];
    shadow.hidden = YES;

    [self swizzled_viewWillAppear:animated];
}

@end

Answer 18

斯威夫特把这个

UINavigationBar.appearance().setBackgroundImage(UIImage(), forBarPosition: .Any, barMetrics: .Default)
UINavigationBar.appearance().shadowImage = UIImage()

在

func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool

Answer 19

Slightly Swift Solution 
func setGlobalAppearanceCharacteristics () {
    let navigationBarAppearace = UINavigationBar.appearance()
    navigationBarAppearace.tintColor = UIColor.white
    navigationBarAppearace.barTintColor = UIColor.blue
    navigationBarAppearace.setBackgroundImage(UIImage(), for: UIBarMetrics.default)
    navigationBarAppearace.shadowImage = UIImage()

}

Answer 20

Swift 4.2中的解决方案：

private func removeHairlineFromNavbar() {
    UINavigationBar.appearance().setBackgroundImage(
        UIImage(),
        for: .any,
        barMetrics: .default)
    UINavigationBar.appearance().shadowImage = UIImage()
}

只需将此函数放在第一个Viewcontroller上并调用 viewdidload

Answer 21

对我有用的两行解决方案。尝试在 ViewDidLoad 方法中添加：

navigationController?.navigationBar.setValue(true, forKey: "hidesShadow")
self.extendedLayoutIncludesOpaqueBars = true