如何在导航栏中全局添加阴影和删除底线？

Question

所以我正在寻找如何向 NavigationBar 添加阴影并从 NavigationBar 中删除底部黑线？此外，如果我在 NavigationBar 中有 searchBar，那么阴影应该在搜索栏下方。我想在不改变每个 viewController 的情况下进行全局更改。

https://imgur.com/a/8ogGRaf.jpg

所以我已经存档了这些更改，除了在下面添加一个阴影到搜索控制器。

1. 对于阴影：

   self.navigationController?.navigationBar.isTranslucent = false
   self.navigationController?.navigationBar.layer.shadowColor = UIColor.black.cgColor
   self.navigationController?.navigationBar.layer.shadowOffset = CGSize(width: 0.0, height: 0.0)
   self.navigationController?.navigationBar.layer.shadowRadius = 7.0
   self.navigationController?.navigationBar.layer.shadowOpacity = 0.2
   

2. 对于删除底栏：

   UINavigationBar.appearance().backIndicatorImage = UIImage(named:"normal")
   UINavigationBar.appearance().backIndicatorTransitionMaskImage = UIImage(named:"normal")
   

这是我在搜索栏遇到的问题

https://imgur.com/a/QQ9yrbE

Answer 1

2.隐藏底线

public extension UINavigationBar {

    /// Hide line under navigation bar
    public func hideBottomHairline() {
        let navigationBarImageView = hairlineImageViewInNavigationBar(self)
        navigationBarImageView!.isHidden = true
    }

    ///  Show line under navigation bar
    public func showBottomHairline() {
        let navigationBarImageView = hairlineImageViewInNavigationBar(self)
        navigationBarImageView!.isHidden = false
    }

    fileprivate func hairlineImageViewInNavigationBar(_ view: UIView) -> UIImageView? {
        if view.isKind(of: UIImageView.self) && view.bounds.height <= 1.0 {
            return (view as! UIImageView)
        }
        let subviews = (view.subviews as [UIView])
        for subview: UIView in subviews {
            if let imageView: UIImageView = hairlineImageViewInNavigationBar(subview) {
                return imageView
            }
        }
        return nil
    }   
}