更改导航栏底部边框颜色 Swift
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【中文标题】更改导航栏底部边框颜色 Swift【英文标题】:Change navigation bar bottom border color Swift 【发布时间】:2016-07-13 15:00:02 【问题描述】: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
但是当我添加 UITableView 时它不会出现在上面,当我添加 UISearchView 时它会出现但会删除导航栏。
有人知道怎么解决吗?
【问题讨论】:
【参考方案1】:您必须调整导航栏的shadowImage
属性。
试试这个。我在 UIColor 上创建了一个类别作为助手,但您可以按照自己喜欢的方式进行重构。
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
选项 1:在单个导航栏上
然后在您的视图控制器中(将 UIColor 更改为您喜欢的):
// We can use a 1px image with the color we want for the shadow image
self.navigationController?.navigationBar.shadowImage = UIColor.redColor().as1ptImage()
// We need to replace the navigation bar's background image as well
// in order to make the shadowImage appear. We use the same 1px color tecnique
self.navigationController?.navigationBar.setBackgroundImage(UIColor.yellowColor().as1ptImage(), forBarMetrics: .Default)
选项 2:在所有导航栏上使用外观代理
不用在每个导航栏上设置背景图片和阴影图片,可以依赖 UIAppearance 代理。您可以尝试将这些行添加到您的 AppDelegate,而不是在 viewDidLoad 中添加之前的行。
// We can use a 1px image with the color we want for the shadow image
UINavigationBar.appearance().shadowImage = UIColor.redColor().as1ptImage()
// We need to replace the navigation bar's background image as well
// in order to make the shadowImage appear. We use the same 1px color technique
UINavigationBar.appearance().setBackgroundImage(UIColor.yellowColor().as1ptImage(), forBarMetrics: .Default)
【讨论】:
谢谢,我应该把扩展 UIColor 放在哪里? 随心所欲。如果你有其他 UIColor 扩展,你可以把它们放在一起,或者你可以为这个扩展创建一个新文件,或者你可以将扩展设为私有并与 UIViewController 类一起使用。 我之所以问,是因为它显示了一条错误消息“声明仅在文件范围内有效”。 是的,你不能把放在你的班级里。成功了吗? 我正在尝试将它添加到 UITableView 上,但它不起作用。我也试图将它添加到搜索视图上,它可以工作,但会删除导航栏的颜色。知道如何解决这个问题吗?【参考方案2】:@TheoF、@Alessandro 和 @Pavel 的精彩贡献。
这就是我所做的……
斯威夫特 4
extension UIColor
/// Converts this `UIColor` instance to a 1x1 `UIImage` instance and returns it.
///
/// - Returns: `self` as a 1x1 `UIImage`.
func as1ptImage() -> UIImage
UIGraphicsBeginImageContext(CGSize(width: 1, height: 1))
setFill()
UIGraphicsGetCurrentContext()?.fill(CGRect(x: 0, y: 0, width: 1, height: 1))
let image = UIGraphicsGetImageFromCurrentImageContext() ?? UIImage()
UIGraphicsEndImageContext()
return image
在viewDidLoad()
中使用它:
/* In this example, I have a ViewController embedded in a NavigationController in IB. */
// Remove the background color.
navigationController?.navigationBar.setBackgroundImage(UIColor.clear.as1ptImage(), for: .default)
// Set the shadow color.
navigationController?.navigationBar.shadowImage = UIColor.gray.as1ptImage()
【讨论】:
【参考方案3】:将@alessandro-orru 的答案放在一个扩展中
extension UINavigationController
func setNavigationBarBorderColor(_ color:UIColor)
self.navigationBar.shadowImage = color.as1ptImage()
extension UIColor
/// Converts this `UIColor` instance to a 1x1 `UIImage` instance and returns it.
///
/// - Returns: `self` as a 1x1 `UIImage`.
func as1ptImage() -> UIImage
UIGraphicsBeginImageContext(CGSize(width: 1, height: 1))
setFill()
UIGraphicsGetCurrentContext()?.fill(CGRect(x: 0, y: 0, width: 1, height: 1))
let image = UIGraphicsGetImageFromCurrentImageContext() ?? UIImage()
UIGraphicsEndImageContext()
return image
然后在您的视图控制器中添加:
self.navigationController?.setNavigationBarBorderColor(UIColor.red)
【讨论】:
我更喜欢这个答案!干净简单,在 Swift 4+ 中工作【参考方案4】:从 ios 13 开始,您可以将 UINavigationBarAppearance()
类与 shadowColor
属性一起使用:
if #available(iOS 13.0, *)
let style = UINavigationBarAppearance()
style.shadowColor = UIColor.clear // Effectively removes the border
navigationController?.navigationBar.standardAppearance = style
// Optional info for follow-ups:
// The above will override other navigation bar properties so you may have to assign them here, for example:
//style.buttonAppearance.normal.titleTextAttributes = [.font: UIFont(name: "YourFontName", size: 17)!]
//style.backgroundColor = UIColor.orange
//style.titleTextAttributes = [NSAttributedString.Key.foregroundColor: UIColor.white,
NSAttributedString.Key.font: UIFont(name: "AnotherFontName", size: 20.0)!]
else
// Fallback on earlier versions
【讨论】:
【参考方案5】:Swift 4.0 - 5.2 的解决方案
这是用于更改底部导航栏线的高度和颜色的小扩展
extension UINavigationController
func addCustomBottomLine(color:UIColor,height:Double)
//Hiding Default Line and Shadow
navigationBar.setValue(true, forKey: "hidesShadow")
//Creating New line
let lineView = UIView(frame: CGRect(x: 0, y: 0, width:0, height: height))
lineView.backgroundColor = color
navigationBar.addSubview(lineView)
lineView.translatesAutoresizingMaskIntoConstraints = false
lineView.widthAnchor.constraint(equalTo: navigationBar.widthAnchor).isActive = true
lineView.heightAnchor.constraint(equalToConstant: CGFloat(height)).isActive = true
lineView.centerXAnchor.constraint(equalTo: navigationBar.centerXAnchor).isActive = true
lineView.topAnchor.constraint(equalTo: navigationBar.bottomAnchor).isActive = true
添加此扩展后,您可以在任何 UINavigationController 上调用此方法(例如来自 ViewController viewDidLoad()
)
self.navigationController?.addCustomBottomLine(color: UIColor.black, height: 20)
【讨论】:
【参考方案6】:对于 Swift 3.0 只需更改此行:
CGContextFillRect(ctx, CGRect(x: 0, y: 0, width: 1, height: 1))
对此:
ctx?.fill(CGRect(x: 0, y: 0, width: 1, height: 1))
【讨论】:
【参考方案7】:现在有更好的选择:
UINavigationBar.appearance().shadowImage = UIImage()
【讨论】:
【参考方案8】:适用于 iOS 13 及更高版本
guard let navigationBar = navigationController?.navigationBar else return
navigationBar.isTranslucent = true
if #available(iOS 13.0, *)
let appearance = UINavigationBarAppearance()
appearance.configureWithTransparentBackground()
appearance.backgroundImage = UIImage()
appearance.backgroundColor = .clear
navigationBar.standardAppearance = appearance
else
navigationBar.setBackgroundImage(UIImage(), for: .default)
navigationBar.shadowImage = UIImage()
【讨论】:
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