Swift是否可以将NSTextview指定为尚未创建的全局视图?

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我想做一个文本编辑器,可以预览降价文件。

当前状态 :
读/写文本文件工作正常。

问题:

这是我的密码: 向下导入//md转换库

class Document: NSDocument {

    var string = ""
    var ref: NSTextView

    override init() {
        self.ref = NSTextView()
        super.init()
    }

    override class var autosavesInPlace: Bool {
        return true
    }

    override func makeWindowControllers() {

        // Returns the Storyboard that contains your Document window.
        let storyboard = NSStoryboard(name: NSStoryboard.Name("Main"), bundle: nil)
        // creates a new windowController on the fly when a new file is openend. That creates the new window...
        let windowController = storyboard.instantiateController(withIdentifier: NSStoryboard.SceneIdentifier("Document Window Controller")) as! NSWindowController
        // the windowController contains a viewController
        self.addWindowController(windowController)

        // create reference to the textView inside the window we just created by opening the new file...
        let vc = windowController.contentViewController as! ViewController

        // THIS DOES NOT SEEM TO WORK
        self.ref = vc.textView            
    }

    override func data(ofType typeName: String) throws -> Data {
        // SAVE BACK TO FILE
        if let vc = self.windowControllers[0].contentViewController as? ViewController {
            return vc.textView.string.data(using: String.Encoding.utf8) ?? Data()
        }
        else {
            return Data()
        }

    }

    override func read(from data: Data, ofType typeName: String) throws {
        do {
            let s = try String(data: data, encoding: .utf8)                
            let down = Down(markdownString: s!)

            let fancyString = try! down.toAttributedString()
            //self.ref.insertText(fancyString, replacementRange: NSRange(location: 0, length: 10))
            self.ref.insertText("It might be working...", replacementRange: NSRange(location: 0, length: 10))

        }

    }

}

以下是我认为正在发生的事情: 为了构建这个代码,我需要分配一个 NSTextView() 实例到 self.ref 在里面 init() makeWindowControllers() ,但这似乎不起作用。

我希望看到 It might be working...

有什么想法吗?

更新

感谢@Willeke提出这个问题。我以为 makeWindowControllers() 是第一个打电话的。结果是 read() 被称为然后 makeWindowControllers()

所以我可以分配 var fancyString:NSAttributedString = NSAttributedString(string: "hello") 作为类变量。然后设置 fancyString 从中的文件内容 并在中更新textView makeWindowControllers 像这样:

 // the proper way to insert an NSAttributedString into a textView
 vc.textView.insertText(fancyString, replacementRange: NSRange(location: 0, length: 10))