ios - 对 Swift 方法参数的理解存在问题

Question

在下面的方法中，参数声明中的launchOptions是什么？它是 NSObject 类型数组的可选吗？我对 swift 还很陌生，所以这听起来可能很傻，但我不明白 didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]? 是什么意思。非常感谢任何帮助:)

func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
    self.window = UIWindow(frame:UIScreen.mainScreen().bounds)
    self.window!.backgroundColor = UIColor.whiteColor()
    self.window!.makeKeyAndVisible()
    return true
}

Answer 1

这就是 swift 转换 NSArray 的方式。

Swift bridges between the Array type and the NSArray class. When you bridge from an NSArray object to a Swift array, the resulting array is of type [AnyObject]. An object is AnyObject compatible if it is an instance of an Objective-C or Swift class, or if the object can be bridged to one. You can bridge any NSArray object to a Swift array because all Objective-C objects are AnyObject compatible. Because all NSArray objects can be bridged to Swift arrays, the Swift compiler replaces the NSArray class with [AnyObject] when it imports Objective-C APIs

here you can find more about Cocoa data types