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。

我需要同时做到这两点:

设置显示样式为全屏 设置顶部栏为半透明导航栏

这很容易做到 打开你的故事板作为源代码，搜索kind="presentation"，在所有带有kind= presentation的segue标签中添加一个额外的属性modalPresentationStyle="fullScreen"

以上的答案和建议是正确的，下面是另一个版本，和有效的方法使用编程。

创建一个UIView扩展

创建一个方法()

//#1
extension UIViewController {

//#2
func presentLocal(_ viewControllerToPresent: UIViewController, animated flag: 
Bool, completion: (() -> Void)? = nil) {

//Reusing below 2 lines :-)
viewControllerToPresent.modalPresentationStyle = .overCurrentContext
self.present(viewControllerToPresent, animated: flag, completion: completion)

  }
}

调用如下所示

let vc = MyViewController()
let nc = UINavigationController(rootViewController: vc)
sourceView.presentLocal(nc, animated: true, completion: nil)

OR

let vc = MyViewController()
sourceView.presentLocal(vc, animated: true, completion: nil)

我在ios 13中使用了swizzling

import Foundation
import UIKit

private func _swizzling(forClass: AnyClass, originalSelector: Selector, swizzledSelector: Selector) {
    if let originalMethod = class_getInstanceMethod(forClass, originalSelector),
       let swizzledMethod = class_getInstanceMethod(forClass, swizzledSelector) {
        method_exchangeImplementations(originalMethod, swizzledMethod)
    }
}

extension UIViewController {

    static let preventPageSheetPresentation: Void = {
        if #available(iOS 13, *) {
            _swizzling(forClass: UIViewController.self,
                       originalSelector: #selector(present(_: animated: completion:)),
                       swizzledSelector: #selector(_swizzledPresent(_: animated: completion:)))
        }
    }()

    @available(iOS 13.0, *)
    @objc private func _swizzledPresent(_ viewControllerToPresent: UIViewController,
                                        animated flag: Bool,
                                        completion: (() -> Void)? = nil) {
        if viewControllerToPresent.modalPresentationStyle == .pageSheet
                   || viewControllerToPresent.modalPresentationStyle == .automatic {
            viewControllerToPresent.modalPresentationStyle = .fullScreen
        }
        _swizzledPresent(viewControllerToPresent, animated: flag, completion: completion)
    }
}

然后放这个

UIViewController.preventPageSheetPresentation

的某个地方

例如在AppDelegate中

func application(_ application: UIApplication,
                 didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey : Any]?) -> Bool {

    UIViewController.preventPageSheetPresentation
    // ...
    return true
}

let Obj = MtViewController()
Obj.modalPresentationStyle = .overFullScreen
self.present(Obj, animated: true, completion: nil)

//如果你想禁用滑动来消除它，添加行

Obj.isModalInPresentation = true

查看苹果文档获取更多信息。