使用開關更改UITabBar樣式

Question

我正在嘗試進行黑暗模式切換。 我從本教程（ 鏈接 ）開始，但我無法更改tabBar的樣式。 navBar的樣式發生了變化，但tabBar保持不變。

如何在不重新啟動應用程序的情況下更改tabBar的外觀？

更新＃1：這是我使用的代碼

import UIKit

enum Theme: Int {
    case Light, Dark

    var barStyle: UIBarStyle {
        switch self {
        case .Light:
            return .Default
        case .Dark:
            return .Black
        }
    }

    var backgroundColor: UIColor {
        switch self {
        case .Light:
            return UIColor(red:0.95, green:0.95, blue:0.95, alpha:1.00)
        case .Dark:
            return UIColor(red:0.12, green:0.12, blue:0.12, alpha:1.00)
        }
    }

    var cellBackgroundColor: UIColor {
        switch self {
        case .Light:
            return UIColor(red:1.00, green:1.00, blue:1.00, alpha:1.00)
        case .Dark:
            return UIColor(red:0.15, green:0.15, blue:0.15, alpha:1.00)
        }
    }

    var labelColor: UIColor {
        switch self {
        case .Light:
            return UIColor(red:0.12, green:0.12, blue:0.12, alpha:1.00)
        case .Dark:
            return UIColor(red:0.99, green:0.99, blue:0.99, alpha:1.00)
        }
    }

    var buttonColor: UIColor {
        switch self {
        case .Light:
            return UIColor(red:0.22, green:0.59, blue:0.95, alpha:1.00)
        case .Dark:
            return UIColor(red:0.22, green:0.59, blue:0.95, alpha:1.00)
        }
    }

    var separatorColor: UIColor {
        switch self {
        case .Light:
            return UIColor(red:0.94, green:0.94, blue:0.94, alpha:1.00)
        case .Dark:
            return UIColor(red:0.22, green:0.22, blue:0.22, alpha:1.00)
        }
    }

    var tintColor: UIColor {
        switch self {
        case .Light:
            return UIColor(red:0.62, green:0.62, blue:0.62, alpha:1.00)
        case .Dark:
            return UIColor(red:0.50, green:0.50, blue:0.50, alpha:1.00)
        }
    }
}

class ThemeManager {
    static func currentTheme() -> Theme {
        if(NSUserDefaults.standardUserDefaults().boolForKey("darkMode")){
            return .Dark
        } else {
            return .Light
        }
    }

    static func applyTheme(theme: Theme) {
        if(theme == .Dark){
            NSUserDefaults.standardUserDefaults().setBool(true, forKey: "darkMode")
        } else {
            NSUserDefaults.standardUserDefaults().setBool(false, forKey: "darkMode")
        }
        NSUserDefaults.standardUserDefaults().synchronize()

        let sharedApplication = UIApplication.sharedApplication()
        sharedApplication.delegate?.window??.tintColor = theme.buttonColor

        UINavigationBar.appearance().barStyle = theme.barStyle
        UITabBar.appearance().barStyle = theme.barStyle
        UITabBar.appearance().barTintColor = theme.labelColor

        UINavigationBar.appearance().tintColor = theme.labelColor

        UITableViewCell.appearance().backgroundColor = theme.cellBackgroundColor

        UIStepper.appearance().tintColor = theme.tintColor
        UIActivityIndicatorView.appearance().tintColor = theme.tintColor

        UIButton.appearance().tintColor = theme.buttonColor
        UILabel.appearance().textColor = theme.labelColor
    }
}

當開關狀態改變時，我調用ThemeManager.applyTheme(.Dark || .Light) 。

Answer 1

UIAppearance代理僅影響新的初始化視圖。 在UIAppearance上設置顏色和樣式不會對已經可見的視圖產生影響。

您必須在ViewController中手動設置它：

self.tabBarController?.tabBar.barStyle = .Black