在运行时更改UITabBar.appearance().tintColor

Question

我想让用户改变整个应用程序的颜色。但是每当我选择一种颜色时，它只会在应用程序重启后才会改变。

是否有在运行时更改颜色的选项？

我已经使用如下函数设置了一个Button来创建一个ColorPicker

@IBAction func colorChange(_ sender: UIButton) {
        // Initializing Color Picker
        let picker = UIColorPickerViewController()

        // Setting the Initial Color of the Picker
        picker.selectedColor = UIColor(named: "MyGreen")!

        // Setting Delegate
        picker.delegate = self

        // Presenting the Color Picker
        self.present(picker, animated: true, completion: nil)
    }

当用户选择一种颜色时，我会在此函数中进行更改

func colorPickerViewControllerDidFinish(_ viewController: UIColorPickerViewController) {
        defaults.set(viewController.selectedColor, forKey: "myColor")
        UITabBar.appearance().tintColor = viewController.selectedColor
    }

为了在启动时更改颜色，我在AppDelegate中实现了这一点

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
        var myColor = defaults.color(forKey: "myColor")
        if  myColor == nil {
            myColor = UIColor(named: "MyGreen")
        }
        UITabBar.appearance().tintColor = myColor
        
        return true
    }

Answer 1

有人给了我一篇文章，让我看看如何做到这一点。https://zamzam.io/protocol-oriented-themes-for-ios-apps/

我最终是这样做的：

 func colorPickerViewControllerDidFinish(_ viewController: UIColorPickerViewController) {
        defaults.set(viewController.selectedColor, forKey: "myColor")
        apply(for: UIApplication.shared, color: viewController.selectedColor)
    }

通过添加此函数

func apply(for application: UIApplication, color: UIColor) {
        UITabBar.appearance().tintColor = color
        application.windows.reload()
    }

和这些扩展

public extension UIWindow {

    /// Unload all views and add back.
    /// Useful for applying `UIAppearance` changes to existing views.
    func reload() {
        subviews.forEach { view in
            view.removeFromSuperview()
            addSubview(view)
        }
    }
}

public extension Array where Element == UIWindow {
    
    /// Unload all views for each `UIWindow` and add back.
    /// Useful for applying `UIAppearance` changes to existing views.
    func reload() {
        forEach { $0.reload() }
    }
}

我不知道它是好是坏--但它对我很有效。

Answer 2

你试过使用UITabBar.appearance().barTintColor吗？