问尽管指示成功，UIDocument仍未保存到文件

EN

var saveFile: SBDocument?

@IBAction func bbiOpen_pressed(_ sender: UIBarButtonItem) {

    if saveFile == nil {
        let importMenu = UIDocumentMenuViewController(documentTypes: self.UTIs, in: .import)
        importMenu.delegate = self
        importMenu.popoverPresentationController?.barButtonItem = bbiOpen
        self.present(importMenu, animated: true, completion: nil)
    } else {
        willClose()
    }

}

func willClose(_ action: UIAlertAction?) {
    if saveFile!.hasUnsavedChanges {
        dlgYesNoCancel(self, title: "Save Changes?", message: "Would you like to save the changes to your document before closing?", onYes: doSaveAndClose, onNo: doClose, onCancel: nil)
    } else {
        doSaveAndClose(action)
    }
}

func doSaveAndClose(_ action: UIAlertAction?) {
    saveFile?.save(to: saveFileURL!, for: .forOverwriting, completionHandler: { Void in
        self.saveFile?.close(completionHandler: self.didClose)
    })
}

func documentPicker(_ controller: UIDocumentPickerViewController, didPickDocumentAt url: URL) {
    saveFile = SBDocument(fileURL: url)
    saveFile!.open(completionHandler: { success in self.finishOpen(didCompleteSuccessfully: success) })
}

func finishOpen(didCompleteSuccessfully result: Bool) {
    if result {
        print(saveFile!.localizedName)
        saveFileURL = saveFile!.fileURL
        saveFileName = saveFile!.localizedName
        self.navTitleBar.prompt = saveFileName
        bbiOpen.title = NSLocalizedString("titleClose", comment: "Close")
        bbiOpen.style = .plain
    } else {
        saveFile = nil
    }
}

@IBAction func bbiSave_pressed(_ sender: UIBarButtonItem) {
    self.saveFile!.save(to: self.saveFileURL!, for: .forOverwriting, completionHandler: self.didSave)
}

func didSave(_ success: Bool) {
    guard success else {
        print("Error saving soundboard file to \(String(describing: saveFileURL))")
        return
    }
    print("File saved successfully")        
}

class SBDocument: UIDocument {
    override var fileType: String? { get { return "com.whitehatenterprises.SoundBoardFX.sbd" } }
    override var savingFileType: String? { get { return "com.whitehatenterprises.SoundBoardFX.sbd" } }

    override init(fileURL url: URL) {
        super.init(fileURL: url)
    }

    override func contents(forType typeName: String) throws -> Any {
        let arr = NSArray(array: SoundEffects)
        let data: NSData = NSKeyedArchiver.archivedData(withRootObject: arr) as NSData
        return data
    }
}