xcode 在应用程序委托中获取主窗口控制器的实例

Get instance of main window controller in app delegate

提问by redeyes

I know that, for iOS, you can reference the root view controller from the app delegate like so:

我知道，对于 iOS，您可以从应用程序委托中引用根视图控制器，如下所示：

var rootViewController = self.window!.rootViewController

var rootViewController = self.window!.rootViewController

How does one reference the main window controller from the app delegate when targeting OS X? I would like to pass a variable (the managed object context) this way, as I have read that it is a good solution for referencing the moc.

以 OS X 为目标时，如何从应用程序委托中引用主窗口控制器？我想以这种方式传递一个变量（托管对象上下文），因为我已经读到它是引用 moc 的一个很好的解决方案。

回答by seb

You can access the NSWindowController instance of the main NSWindow like this:

你可以像这样访问主 NSWindow 的 NSWindowController 实例：

NSApplication.sharedApplication().mainWindow?.windowController

回答by Phill Apley

The ! in earlier answers will cause a crash if the window is hidden, so I recommend caching the window either like this or using a computed property:

这 ！如果窗口被隐藏，在早期的答案中会导致崩溃，所以我建议像这样或使用计算属性缓存窗口：

var mWindow: NSWindow? = nil
func mainWindowCached() -> NSWindow? {
    if let window = NSApplication.shared.mainWindow {
        self.mWindow = window
    }
    return self.mWindow
}

回答by Parvesh

You can access like this:

您可以这样访问：

NSApplication.shared().mainWindow?.contentViewController as! YourViewController;