ios - Swift ios 不确定我是否正确使用完成处理程序

Question

当我登录到我的应用程序时，我将删除两个显示为模态的 VC，然后添加一个新的 VC 并通过以下方式使其成为根 VC:

@IBAction func loginButtonDidTouch(sender: AnyObject) {
    let storyboard: UIStoryboard = UIStoryboard(name: "Main", bundle: nil)

    let AccountVc = storyboard.instantiateViewControllerWithIdentifier("AccountVc")

    let navigationController = self.view.window?.rootViewController as! UINavigationController        

    self.presentingViewController!.presentingViewController!.dismissViewControllerAnimated(false) { () -> Void in                
        navigationController.setViewControllers([AccountVc], animated: true)                
    }
}

我想确保 navigationController.setViewControllers([AccountVc], animated: true) 运行一次 self.presentingViewController!.presentingViewController!.dismissViewControllerAnimated(false) 完成了。

它可以工作，但我不确定这是否是正确的写法？

我在写:{ () -> Void in 我看到一些例子，人们只写它而没有 Void。

Answer 1

两种方式都是对的。这称为 Trailing Closures。

func someFunctionThatTakesAClosure(closure: () -> Void) {
    // function body goes here
}

// here's how you call this function without using a trailing closure:

someFunctionThatTakesAClosure({
    // closure's body goes here
})

// here's how you call this function with a trailing closure instead:

someFunctionThatTakesAClosure() {
    // trailing closure's body goes here
}

查看更多信息 Apple Document