Swift | iOS开发之Swift入门-AppDelegate

在进行iOS开发时，和之前使用OC一样，默认使用storyboard，所以无需在AppDelegate中进行任何操作（push除外）。

不使用storyboard的纯代码需要增加如下代码：（文中代码为swift3.0）

1. 非navigationController

    var window: UIWindow?
    var viewController: UIViewController?

    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
        // Override point for customization after application launch.
        self.window = UIWindow.init(frame: UIScreen.main.bounds)
        let vc = ViewController()
        self.viewController = vc
        self.window?.rootViewController = self.viewController
        self.window?.makeKeyAndVisible()
        return true
    }

2. navigationController

    var window: UIWindow?
    var viewController: UINavigationController?

    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
        // Override point for customization after application launch.
        self.window = UIWindow.init(frame: UIScreen.main.bounds)
        let vc = ViewController()
        self.viewController = UINavigationController.init(rootViewController: vc)
        self.window?.rootViewController = self.viewController
        self.window?.makeKeyAndVisible()
        return true
    }