如何在以編程方式創建標籤欄控制器後添加導航界面（Swift）

Question

在AppDelegate/didFinishLaunchingWithOptions上創建TabBarController後，如何在Swift上以編程方式添加導航界面。這裏是我目前的代碼：

self.window = UIWindow(frame: UIScreen.mainScreen().bounds) 


    let tabBarController = UITabBarController() 
    let purchaseViewController = PurchaseViewController(nibName: "PurchaseViewController", bundle: nil) 
    let financeViewController = FinanceViewController(nibName: "FinanceViewController", bundle: nil) 



    tabBarController.viewControllers = [purchaseViewController, financeViewController] 

    self.window!.rootViewController = tabBarController 
    self.window!.makeKeyAndVisible() 

我正在查看文檔。它有以下指導原則

- (void)applicationDidFinishLaunching:(UIApplication *)application { 
self.tabBarController = [[UITabBarController alloc] init]; 

MyViewController1* vc1 = [[MyViewController1 alloc] init]; 
MyViewController2* vc2 = [[MyViewController2 alloc] init]; 
MyViewController3* vc3 = [[MyViewController3 alloc] init]; 
MyNavRootViewController* vc4 = [[MyNavRootViewController alloc] init]; 
UINavigationController* navController = [[UINavigationController alloc] 
         initWithRootViewController:vc4]; 

NSArray* controllers = [NSArray arrayWithObjects:vc1, vc2, vc3, navController, nil]; 
tabBarController.viewControllers = controllers; 

window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]]; 
window.rootViewController = tabBarController; 
[window makeKeyAndVisible]; 
} 

問題，我想不出如何在Swift上正確執行此操作。我期待在AppDelegate中以單獨的方法設置和修改NavigationBar。有什麼想法嗎？

Answer 1

要創建一個導航控制器使用：

var navigationController = UINavigationController(rootViewController: viewController)); 

然後，只需把它放在數組中：

tabBarController.viewControllers = [purchaseViewController, financeViewController, navigationController] 

但是，你可以到UIControls添加到導航欄只有在視圖控制器做負載。在applicationDidFinishLaunching:這是不可能的，因爲navigationBar是零。正確的方法是將控件添加到viewDidLoad中的navigationBar（）