Question

我为UITabBar和UITabBarController有自定义类。定制的UITabBar定义了一个按钮，当按下该按钮时应打开TabBar中的正确选项卡。但是，我似乎无法获得正确的代码来打开选项卡。

如何访问我的自定义UITabBarController来更改选项卡，否则可以直接从UITabBar更改当前选项卡吗？

class MainTabBar: UITabBar {

private var middleButton = UIButton()

override func awakeFromNib() {
    super.awakeFromNib()
    setupMiddleButton()
}

override func hitTest(_ point: CGPoint, with event: UIEvent?) -> UIView? {
    if self.isHidden {
        return super.hitTest(point, with: event)
    }

    let from = point
    let to = middleButton.center

    return sqrt((from.x - to.x) * (from.x - to.x) + (from.y - to.y) * (from.y - to.y)) <= 39 ? middleButton : super.hitTest(point, with: event)
}

func setupMiddleButton() {
    middleButton.frame.size = CGSize(width: 70, height: 70)
    middleButton.backgroundColor = .white
    middleButton.layer.borderWidth = 2
    middleButton.layer.borderColor = self.tintColor.cgColor
    if let image = UIImage(named: "create") {
        middleButton.setImage(image, for: .normal)
    }
    middleButton.layer.cornerRadius = 35
    middleButton.layer.masksToBounds = true
    middleButton.center = CGPoint(x: UIScreen.main.bounds.width / 2, y: 0)
    middleButton.addTarget(self, action: #selector(click), for: .touchUpInside)
    addSubview(middleButton)
}

@objc func click() {

   }
}

和控制器：

class CustomTabBarController: UITabBarController {

let button = UIButton.init(type: .custom)

override func viewDidLoad() {
    super.viewDidLoad()
    delegate = self
    }
}

extension CustomTabBarController: UITabBarControllerDelegate {
func tabBarController(_ tabBarController: UITabBarController, shouldSelect viewController: UIViewController) -> Bool {
    guard let index = viewControllers?.index(of: viewController) else {
        return false
    }

    if index == 4 {

        let alert = UIAlertController(title: "What do you need?", message: "Please choose between Support and Training", preferredStyle: .actionSheet)

        let action1 = UIAlertAction(title: "Support", style: .default) { (action:UIAlertAction) in
            tabBarController.selectedIndex = 0
            ChoiceStruct.choice = "support"
            tabBarController.selectedIndex = 4
        }

        let action2 = UIAlertAction(title: "Cancel", style: .cancel) { (action:UIAlertAction) in
            // Do nothing
        }

        let action3 = UIAlertAction(title: "Training", style: .default) { (action:UIAlertAction) in
            tabBarController.selectedIndex = 0
            ChoiceStruct.choice = "training"
            tabBarController.selectedIndex = 4
        }

        alert.addAction(action1)
        alert.addAction(action2)
        alert.addAction(action3)

        present(alert, animated: true, completion: nil)
        return false
    }

    return true
}
}

目的是从MainTabBar类中访问tabBarController.selectedIndex，以更改所选的标签

Answer 1

我发现最好的解决方案是将按钮的代码移到UITabBarController上，而不是为此目的而有一个自定义的UITabBar类

从自定义UITabBar访问自定义UITabBarController

1 个答案: