Ios 导航栏的圆角和阴影

我想创建如下内容：

这就是我迄今为止所尝试的：

class RoundedShadowCorners {
    func shadowTopBar(_ topBar: UINavigationBar,_ offset: CGFloat,_ navigationItem: UINavigationItem){
        topBar.isTranslucent = false
        topBar.tintColor = UIColor.orange

        topBar.setBackgroundImage(UIImage(), for: UIBarMetrics.default)
        topBar.shadowImage = UIImage()
        topBar.backgroundColor = UIColor.white
        let shadowView = UIView(frame: CGRect(x: 0, y: -offset, width: (topBar.bounds.width), height: (topBar.bounds.height) + offset))
        shadowView.backgroundColor = UIColor.white
        topBar.insertSubview(shadowView, at: 1)

        let shadowLayer = CAShapeLayer()
        shadowLayer.path = UIBezierPath(roundedRect: shadowView.bounds, byRoundingCorners: [.bottomLeft , .bottomRight , .topLeft], cornerRadii: CGSize(width: 20, height: 20)).cgPath

        shadowLayer.fillColor = UIColor.white.cgColor

        shadowLayer.shadowColor = UIColor.darkGray.cgColor
        shadowLayer.shadowPath = shadowLayer.path
        shadowLayer.shadowOffset = CGSize(width: 2.0, height: 2.0)
        shadowLayer.shadowOpacity = 0.8
        shadowLayer.shadowRadius = 2

        shadowView.layer.insertSublayer(shadowLayer, at: 0)

        topBar.prefersLargeTitles = true
        topBar.topItem?.title = "HJFSKDJKA"
    }
}

这样做的问题是，这会使标题文本位于实际导航栏的后面，只有在为标题创建新的UIView并尝试将其定位在屏幕上时，我才能使标题文本向前显示，这使得响应非常困难

偏移量为视图。安全区域插图。顶部

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我更愿意在不创建新UIView的情况下执行此操作，因为它会使事情变得复杂，但我甚至无法开始执行此操作。

这是经过更新和测试的代码，需要更新某些行以克服此行为，请查看我的在线评论以了解详细信息

func shadowTopBar(_ topBar: UINavigationBar,_ offset: CGFloat){
    // Set the prefers title style first
    // since this is how navigation bar bounds gets calculated
    // 
    topBar.prefersLargeTitles = true
    topBar.topItem?.title = "HJFSKDJKA"

    topBar.isTranslucent = false
    topBar.tintColor = UIColor.orange

    topBar.setBackgroundImage(UIImage(), for: UIBarMetrics.default)
    topBar.shadowImage = UIImage()
    topBar.backgroundColor = UIColor.white
    // Make your y position to the max of the uiNavigationBar
    // Height should the cornerRadius height, in your case lets say 20
    let shadowView = UIView(frame: CGRect(x: 0, y: topBar.bounds.maxY, width: (topBar.bounds.width), height: 20))
    // Make the backgroundColor of your wish, though I have made it .clear here
    // Since we're dealing it in the shadow layer
    shadowView.backgroundColor = .clear
    topBar.insertSubview(shadowView, at: 1)

    let shadowLayer = CAShapeLayer()
    // While creating UIBezierPath, bottomLeft & right will do the work for you in this case
    // I've removed the extra element from here.
    shadowLayer.path = UIBezierPath(roundedRect: shadowView.bounds, byRoundingCorners: [.bottomLeft , .bottomRight], cornerRadii: CGSize(width: 20, height: 20)).cgPath

    shadowLayer.fillColor = UIColor.white.cgColor
    shadowLayer.shadowColor = UIColor.darkGray.cgColor
    shadowLayer.shadowPath = shadowLayer.path
    // This too you can set as per your desired result
    shadowLayer.shadowOffset = CGSize(width: 2.0, height: 4.0)
    shadowLayer.shadowOpacity = 0.8
    shadowLayer.shadowRadius = 2
    shadowView.layer.insertSublayer(shadowLayer, at: 0)

}

这里有一篇关于这方面的详细文章