Ios 如何为中心选项卡栏项目Swift 4创建自定义操作

我想为中心选项卡栏项创建自定义操作。我的代码是

import UIKit

class ViewController: UITabBarController {

    override func viewDidLoad() {
        super.viewDidLoad()
        
        let homeTabBarItem = generateNavController(vc: HomeViewController(), title: "Home", image:#imageLiteral(resourceName: "address_book"))
        let workOrderTabBarItem = generateNavController(vc: SecondViewController(), title: "Work Order", image: #imageLiteral(resourceName: "address_book") )
        let actionItemTabBarItem = generateNavController(vc: ActionViewController(), title:"", image: #imageLiteral(resourceName: "address_book") )
        let requestTabBarItem = generateNavController(vc: ThirdViewController(), title: "Request", image: #imageLiteral(resourceName: "address_book") )
        let settingsTabBarItem =  generateNavController(vc: FourthViewController(), title: "Settings", image: #imageLiteral(resourceName: "address_book"))

        UINavigationBar.appearance().prefersLargeTitles = true

        viewControllers = [homeTabBarItem, workOrderTabBarItem, actionItemTabBarItem, requestTabBarItem, settingsTabBarItem]
        }
    
    fileprivate func generateNavController(vc: UIViewController, title: String, image: UIImage) -> UINavigationController {
        vc.navigationItem.title = title
        let navController = UINavigationController(rootViewController: vc)
        navController.title = title
        navController.tabBarItem.image = image
        return navController
    }
    func tabBarController(_ tabBarController: UITabBarController, shouldSelect viewController: UIViewController) -> Bool {
        if viewController.isKind(of: ActionViewController.self) {
            let vc =  ActionViewController()
            vc.modalPresentationStyle = .overFullScreen
            self.present(vc, animated: true, completion: nil)
            return false
        }
        return true
    }

}

最初，我的选项卡栏看起来应该是常规的选项卡栏，但当按下中间的项目时，应该会像下面这样弹出屏幕（查看图像）

如果有人能帮我，我将不胜感激。

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*很抱歉，如果帖子格式不正确，这是我第一次在stackoverflow上发帖。

基本上，整个想法是不可能的。此ActionViewController不能同时过两种不同的生活。它不能是一个普通的选项卡栏项目，也不能调用显示的视图控制器。我是否应该将其设置为UIButton，然后为该按钮指定一个操作？是的，这正是我所想的。