界面API实现tabBar红点的显示和隐藏、tarBar文本的显示和隐藏、tabBar的显示和隐藏、动态改变tanBar的图标和文字 完整代码

以下是实现上述功能的完整代码：

import UIKit

class ViewController: UIViewController {

    // MARK: - Properties
    
    private var tabBar: UITabBar!
    private var tabBarItems: [UITabBarItem] = []
    
    // MARK: - View Lifecycle
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // Create tab bar
        createTabBar()
        
        // Add view controllers to tab bar
        let vc1 = UIViewController()
        vc1.tabBarItem = UITabBarItem(title: "Item 1", image: UIImage(named: "icon1"), selectedImage: nil)
        tabBarItems.append(vc1.tabBarItem)
        
        let vc2 = UIViewController()
        vc2.tabBarItem = UITabBarItem(title: "Item 2", image: UIImage(named: "icon2"), selectedImage: nil)
        tabBarItems.append(vc2.tabBarItem)
        
        let vc3 = UIViewController()
        vc3.tabBarItem = UITabBarItem(title: "Item 3", image: UIImage(named: "icon3"), selectedImage: nil)
        tabBarItems.append(vc3.tabBarItem)
        
        let vc4 = UIViewController()
        vc4.tabBarItem = UITabBarItem(title: "Item 4", image: UIImage(named: "icon4"), selectedImage: nil)
        tabBarItems.append(vc4.tabBarItem)
        
        let vc5 = UIViewController()
        vc5.tabBarItem = UITabBarItem(title: "Item 5", image: UIImage(named: "icon5"), selectedImage: nil)
        tabBarItems.append(vc5.tabBarItem)
        
        let viewControllers = [vc1, vc2, vc3, vc4, vc5]
        self.viewControllers = viewControllers
        
        // Set initial selected tab
        self.selectedIndex = 0
        
        // Show red dot on tab bar item 3
        showRedDot(on: 2)
        
        // Hide tab bar item 4 text
        hideTabBarItemText(for: 3)
    }
    
    // MARK: - Tab Bar Helpers
    
    private func createTabBar() {
        tabBar = UITabBar()
        tabBar.translatesAutoresizingMaskIntoConstraints = false
        view.addSubview(tabBar)
        
        NSLayoutConstraint.activate([
            tabBar.leadingAnchor.constraint(equalTo: view.leadingAnchor),
            tabBar.trailingAnchor.constraint(equalTo: view.trailingAnchor),
            tabBar.bottomAnchor.constraint(equalTo: view.bottomAnchor),
            tabBar.heightAnchor.constraint(equalToConstant: 50)
        ])
        
        tabBar.delegate = self
    }
    
    private func showTabBar() {
        UIView.animate(withDuration: 0.3) {
            self.tabBar.frame.origin.y = self.view.frame.height - self.tabBar.frame.height
        }
    }
    
    private func hideTabBar() {
        UIView.animate(withDuration: 0.3) {
            self.tabBar.frame.origin.y = self.view.frame.height
        }
    }
    
    private func showRedDot(on index: Int) {
        guard index < tabBarItems.count else {
            return
        }
        
        let item = tabBarItems[index]
        item.badgeValue = " "
    }
    
    private func hideRedDot(from index: Int) {
        guard index < tabBarItems.count else {
            return
        }
        
        let item = tabBarItems[index]
        item.badgeValue = nil
    }
    
    private func hideTabBarItemText(for index: Int) {
        guard index < tabBarItems.count else {
            return
        }
        
        let item = tabBarItems[index]
        item.setTitleTextAttributes([NSAttributedString.Key.foregroundColor: UIColor.clear], for: .normal)
        item.setTitleTextAttributes([NSAttributedString.Key.foregroundColor: UIColor.clear], for: .selected)
    }
    
    private func showTabBarItemText(for index: Int) {
        guard index < tabBarItems.count else {
            return
        }
        
        let item = tabBarItems[index]
        item.setTitleTextAttributes([NSAttributedString.Key.foregroundColor: UIColor.black], for: .normal)
        item.setTitleTextAttributes([NSAttributedString.Key.foregroundColor: UIColor.black], for: .selected)
    }
    
    private func updateTabBarItem(at index: Int, with title: String? = nil, image: UIImage? = nil) {
        guard index < tabBarItems.count else {
            return
        }
        
        let item = tabBarItems[index]
        
        if let title = title {
            item.title = title
        }
        
        if let image = image {
            item.image = image
        }
    }

}

// MARK: - UITabBarDelegate

extension ViewController: UITabBarDelegate {
    
    func tabBar(_ tabBar: UITabBar, didSelect item: UITabBarItem) {
        // Handle tab bar item selection
    }
    
}

使用时，只需要调用相应的方法即可实现对应的功能。例如，要在第三个 tab bar item 上显示红点，可以调用：

showRedDot(on: 2)

要隐藏第四个 tab bar item 的文本，可以调用：

hideTabBarItemText(for: 3)

要动态改变第二个 tab bar item 的图标和文字，可以调用：

updateTabBarItem(at: 1, with: "New Title", image: UIImage(named: "new_icon"))