iOS - 在呈现另一个视图控制器时堆栈全屏视图控制器

Posted 2023-03-13

【中文标题】iOS - 在呈现另一个视图控制器时堆栈全屏视图控制器

【英文标题】：iOS - stack fullscreen viewController when presenting another viewController

【发布时间】：2020-02-24 19:13:49

【问题描述】：

我有一个带有两个标签的UITabBarViewController。我想在其中一个选项卡中全屏显示 viewController。我使用了以下代码。

    let navCtrl = UINavigationController(rootViewController: eventViewController)
    navCtrl.modalPresentationStyle = .fullScreen        
    self.navigationController?.present(navCtrl, animated: true)

它有效。 EventViewController 是全屏的。但是，当在EventViewController 中呈现另一个viewController 时，EventViewController 仍然是全屏的。但我希望它像往常一样缩小尺寸和堆叠（如图所示）。为此，我将modalPresentationStyle 更改为overCurrentContext。

    let navCtrl = UINavigationController(rootViewController: eventViewController)
    navCtrl.modalPresentationStyle = .overCurrentContext        
    self.navigationController?.present(navCtrl, animated: true)

这样做，但它会导致另一个问题：如果我更改选项卡并关闭 EventViewController，则呈现的 viewController 是 black，如 question 中所述（没有一个答案有帮助） em>。

---

基本上我希望EventController 是全屏的，但在其中显示另一个控制器时会缩小尺寸。怎么做？

更新

一个具有相同问题的简单项目。

class TabBarController: UITabBarController 

    override func viewDidLoad() 
        super.viewDidLoad()
        let ctrl = TabZeroViewController()
        ctrl.tabBarItem.image = UIImage(named: "archived-task")
        ctrl.tabBarItem.title = "One"


        let test = TabOneViewController()
        test.tabBarItem.image = UIImage(named: "Test")
        test.tabBarItem.title = "Test"

        let tabBarList = [ctrl, test ]

        self.viewControllers = tabBarList.map 
            let nav = UINavigationController(rootViewController: $0)
            nav.interactivePopGestureRecognizer?.isEnabled = true
            return nav
        
    




class TabZeroViewController: UITableViewController 


    override func viewDidLoad() 
        super.viewDidLoad()
        self.tableView.delegate = self
        self.tableView.dataSource = self

        self.view.backgroundColor = .white
    

    override func numberOfSections(in tableView: UITableView) -> Int 
        return 1
    

    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int 
        return 10
    

    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell 
        let cell =  UITableViewCell()
        cell.textLabel?.text = "\(indexPath.row)"
        return cell
    

    override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) 
        let ctrl = ModalTableViewController()

        let nav = UINavigationController(rootViewController: ctrl)
        nav.modalPresentationStyle = .fullScreen

        self.navigationController?.present(nav, animated: true)
    



class ModalTableViewController: UITableViewController 
    override func viewDidLoad() 
        self.view.backgroundColor = .red
        let button = UIButton()
        button.setTitle("Cancel", for: .normal)
        button.addTarget(self, action: #selector(dismissModal), for: .allEvents)
        let item = UIBarButtonItem()
        item.customView = button
        self.navigationItem.leftBarButtonItem = item
        self.tableView.dataSource = self
        self.tableView.delegate = self
    

    @objc func dismissModal() 
        self.dismiss(animated: true, completion: nil)
    


    override func numberOfSections(in tableView: UITableView) -> Int 
        return 1
    

    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int 
        return 10
    

    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell 
        let cell =  UITableViewCell()
        cell.textLabel?.text = "Event"
        return cell
    

    override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) 
        let ctrl = EventViewController()
        let nav = UINavigationController(rootViewController: ctrl)
         nav.modalPresentationStyle = .overCurrentContext
        self.navigationController?.present(nav, animated: true)
    



class TabOneViewController: UIViewController 

    override func viewDidLoad() 
        super.viewDidLoad()

    





class EventViewController: UITableViewController 

    override func viewDidLoad() 
        self.view.backgroundColor = .red
        let button = UIButton()
        button.setTitle("Cancel", for: .normal)
        button.addTarget(self, action: #selector(dismissModal), for: .allEvents)
        let item = UIBarButtonItem()
        item.customView = button
        self.navigationItem.leftBarButtonItem = item
        self.tableView.dataSource = self
        self.tableView.delegate = self
    

    @objc func dismissModal() 
        self.dismiss(animated: true, completion: nil)
    


    override func numberOfSections(in tableView: UITableView) -> Int 
        return 1
    

    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int 
        return 10
    

    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell 
        let cell =  UITableViewCell()
        cell.textLabel?.text = "Event"
        return cell
    

    override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) 
        let ctrl = EventViewController()
        let nav = UINavigationController(rootViewController: ctrl)
        self.navigationController?.present(nav, animated: true)
    

将此代码添加到willConnectTo 中的SceneDelegate。

 if let windowScene = scene as? UIWindowScene 
        let window = UIWindow(windowScene: windowScene)
        window.rootViewController = TabBarController()
        self.window = window
        window.makeKeyAndVisible()
    

当您在第一个选项卡上时，选择一个表格单元格以打开 ModalTableViewController。然后更改标签并关闭ModalTableViewController。

【问题讨论】：

首先，您需要更新导航控制器中的视图控制器，但导航控制器旨在用于推送视图控制器。因为它可能会导致意外行为。

我已经运行了相同的流程并且它按预期工作。有一件事要问：以 EventViewController 为根的导航控制器没有显示在整个屏幕上，您如何在显示时更改选项卡。请向我澄清这一点。

您确实提供了一个导航控制器，当您关闭任何不会关闭附加的导航控制器的控制器时，这就是您面临黑屏问题的原因。

@neerajjoshi，按照以下步骤操作，1. 设置 modalPresentationStyle = .overCurrentContext 2. 呈现 viewCtrl 3. 选择另一个选项卡，然后选择相同的选项卡。 4 关闭呈现的viewCtrl。

@mahan ，我可以玩一下你的源代码吗？如果是，那么您可以创建具有此类场景的示例项目并上传到 GitHub。

【参考方案1】：

例如项目 - 在全屏上显示视图会隐藏 TabBar。但是我稍微更改了代码以提出可行的解决方案。可能你会想稍微改变一下，但我希望这能把你推向好的方向:)

实际上需要关闭ModalTableViewController以避免黑屏。

class TabBarController: UITabBarController 

    override func viewDidLoad() 
        super.viewDidLoad()
        let ctrl = TabZeroViewController()
        ctrl.tabBarItem.image = UIImage(named: "archived-task")
        ctrl.tabBarItem.title = "One"


        let test = TabOneViewController()
        test.tabBarItem.image = UIImage(named: "Test")
        test.tabBarItem.title = "Test"

        let tabBarList = [ctrl, test ]

        let viewControllers: [UIViewController] = tabBarList.map 
            let nav = UINavigationController(rootViewController: $0)
            nav.interactivePopGestureRecognizer?.isEnabled = true
            nav.tabBarItem = $0.tabBarItem
            return nav
        

        self.setViewControllers(viewControllers, animated: false)
    

    override var selectedViewController: UIViewController? 
        get return super.selectedViewController
        set 
            if super.selectedViewController?.presentedViewController != nil 
                super.selectedViewController?.dismiss(animated: false, completion: nil)
            
            super.selectedViewController = newValue
        
    




class TabZeroViewController: UITableViewController 


    override func viewDidLoad() 
        super.viewDidLoad()
        self.tableView.delegate = self
        self.tableView.dataSource = self

        self.view.backgroundColor = .white
    

    override func numberOfSections(in tableView: UITableView) -> Int 
        return 1
    

    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int 
        return 10
    

    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell 
        let cell =  UITableViewCell()
        cell.textLabel?.text = "\(indexPath.row)"
        return cell
    

    override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) 
        let ctrl = ModalTableViewController()

        let nav = UINavigationController(rootViewController: ctrl)
        nav.modalPresentationStyle = .currentContext

        self.present(nav, animated: true)
    



class ModalTableViewController: UITableViewController 
    override func viewDidLoad() 
        self.view.backgroundColor = .red
        let button = UIButton()
        button.setTitle("Cancel", for: .normal)
        button.addTarget(self, action: #selector(dismissModal), for: .allEvents)
        let item = UIBarButtonItem()
        item.customView = button
        self.navigationItem.leftBarButtonItem = item
        self.tableView.dataSource = self
        self.tableView.delegate = self
    

    @objc func dismissModal() 
        self.presentingViewController?.dismiss(animated: false, completion: nil)
    


    override func numberOfSections(in tableView: UITableView) -> Int 
        return 1
    

    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int 
        return 10
    

    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell 
        let cell =  UITableViewCell()
        cell.textLabel?.text = "Event"
        return cell
    

    override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) 
        let ctrl = EventViewController()
        let nav = UINavigationController(rootViewController: ctrl)
         nav.modalPresentationStyle = .fullScreen
        self.navigationController?.present(nav, animated: true)
    



class TabOneViewController: UIViewController 

    override func viewDidLoad() 
        super.viewDidLoad()
        view.backgroundColor = .white
    





class EventViewController: UITableViewController 

    override func viewDidLoad() 
        self.view.backgroundColor = .red
        let button = UIButton()
        button.setTitle("Cancel", for: .normal)
        button.addTarget(self, action: #selector(dismissModal), for: .allEvents)
        let item = UIBarButtonItem()
        item.customView = button
        self.navigationItem.leftBarButtonItem = item
        self.tableView.dataSource = self
        self.tableView.delegate = self
    

    @objc func dismissModal() 
        self.dismiss(animated: true, completion: nil)
    


    override func numberOfSections(in tableView: UITableView) -> Int 
        return 1
    

    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int 
        return 10
    

    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell 
        let cell =  UITableViewCell()
        cell.textLabel?.text = "Event"
        return cell
    

    override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) 
        let ctrl = EventViewController()
        let nav = UINavigationController(rootViewController: ctrl)
        self.navigationController?.present(nav, animated: true)
    

祝你好运！

【参考方案2】：

试试这个代码以模态方式呈现屏幕：

 func getImageFromView() -> UIImage 

        let layer = UIApplication.shared.keyWindow?.layer
        let scale = UIScreen.main.scale
        UIGraphicsBeginImageContextWithOptions(layer?.frame.size ?? CGSize.zero, false, scale)
        if let context = UIGraphicsGetCurrentContext() 
            layer?.render(in: context)
            let image = UIGraphicsGetImageFromCurrentImageContext()
            UIGraphicsEndImageContext()
            return image ?? UIImage()
        
        return UIImage()
    


/// This is the method to present  screen modally
/// - parameter controller: controller instance on which screen will be presented
func presentScreenModally(controller: UIViewController, animated: Bool) 
    let loginController  = UIStoryboard.loadLoginViewController()//Get instance of controller form storyboard
    loginController.bgTranParentImg = getImageFromView()

    let bgImage = getImageFromView()
    let presentationStyleViewController = UIStoryboard.loadPresentationStyleController()// This is another controller, which I am pasting below
    presentationStyleViewController.bgimage = bgImage
    presentationStyleViewController.loginController = loginController
    presentationStyleViewController.addChild(loginController)
    controller.view.window?.addSubview(presentationStyleViewController.view)
    loginController.view.frame = presentationStyleViewController.containerView.bounds
    presentationStyleViewController.containerView.addSubview(loginController.view)

    let navigationController = UINavigationController(rootViewController: presentationStyleViewController)
    navigationController.navigationBar.isHidden = true
    navigationController.modalPresentationStyle = .fullScreen
    controller.navigationController?.present(navigationController, animated: animated, completion: nil)

PresentationStyleViewController 类：

class PresentationStyleViewController: UIViewController 

    @IBOutlet var containerView: UIView!
    @IBOutlet var containeTopConstraint: NSLayoutConstraint!
    @IBOutlet var containerBottomConstraint: NSLayoutConstraint!
    @IBOutlet var backgroundImage: UIImageView!

    var bgimage: UIImage?
    let topPadding: CGFloat = 30
    var loginController: LoginViewController?

    override func viewDidLoad() 
        super.viewDidLoad()
        self.uiSetup()
    

    override func viewDidAppear(_ animated: Bool) 
        restorePopup()
    

    /// Initial UI setup
    func uiSetup() 
        containeTopConstraint.constant = self.view.frame.size.height
        backgroundImage.image = bgimage
    

    @IBAction func panGesture(_ sender: UIPanGestureRecognizer) 
        guard let piece = sender.view else return
        let translation = sender.translation(in: piece.superview)
        containeTopConstraint.constant = translation.y >= topPadding ? translation.y : topPadding

        if sender.state == .ended || sender.state == .cancelled 
            if containeTopConstraint.constant > self.view.frame.size.height/4 && translation.y > 0 
                self.dismissPopup()
             else 
                self.restorePopup()
            
        
    

    /// Dismisses popup and controller
    func dismissPopup() 
        containeTopConstraint.constant = self.view.frame.size.height
        UIView.animate(withDuration: 0.3,
                       animations: 
                        self.view.layoutIfNeeded()
        , completion:  (_) in
            self.loginController?.btnClick_cross(UIButton())
            self.dismiss(animated: false)
        )
    

    /// Restores popup at initial position
    func restorePopup() 
        containeTopConstraint.constant = topPadding
        UIView.animate(withDuration: 0.3,
                       animations: 
                        self.view.layoutIfNeeded()
        , completion: nil)