我通过使用方法swizzling(Swift 4.2)实现了它:

创建UIViewController扩展，如下所示

extension UIViewController {

    @objc private func swizzled_presentstyle(_ viewControllerToPresent: UIViewController, animated: Bool, completion: (() -> Void)?) {

        if #available(iOS 13.0, *) {
            if viewControllerToPresent.modalPresentationStyle == .automatic || viewControllerToPresent.modalPresentationStyle == .pageSheet {
                viewControllerToPresent.modalPresentationStyle = .fullScreen
            }
        }

        self.swizzled_presentstyle(viewControllerToPresent, animated: animated, completion: completion)
    }

     static func setPresentationStyle_fullScreen() {

        let instance: UIViewController = UIViewController()
        let aClass: AnyClass! = object_getClass(instance)

        let originalSelector = #selector(UIViewController.present(_:animated:completion:))
        let swizzledSelector = #selector(UIViewController.swizzled_presentstyle(_:animated:completion:))

        let originalMethod = class_getInstanceMethod(aClass, originalSelector)
        let swizzledMethod = class_getInstanceMethod(aClass, swizzledSelector)
        if let originalMethod = originalMethod, let swizzledMethod = swizzledMethod {
        method_exchangeImplementations(originalMethod, swizzledMethod)
        }
    }
}

在AppDelegate中，在application:didFinishLaunchingWithOptions中:调用swizzling代码通过调用:

UIViewController.setPresentationStyle_fullScreen()

这对我很有效

let vc = self.storyboard?.instantiateViewController(withIdentifier: "storyboardID_cameraview1") as! CameraViewController
  
vc.modalPresentationStyle = .fullScreen
    
self.present(vc, animated: true, completion: nil)`

最新版本为iOS 13和Swift 5.x

let vc = ViewController(nibName: "ViewController", bundle: nil)

vc。modalPresentationStyle = .fullScreen

self.present(vc, animated: true, completion: nil)

我在启动屏幕后的初始视图中遇到了这个问题。修复我，因为我没有一个segue或逻辑定义是切换演示从自动到全屏如下所示:

我添加的信息可能对某人有用。如果你有任何故事板segue，要回到旧的风格，你需要将kind属性设置为modal Present，并将Presentation属性设置为全屏。

正如在2019年全球开发者大会上发布的平台国情咨文中所述，苹果在iOS 13中引入了新的默认卡显示方式。为了强制全屏，你必须明确地指定它:

let vc = UIViewController()
vc.modalPresentationStyle = .fullScreen //or .overFullScreen for transparency
self.present(vc, animated: true, completion: nil)