如何告诉NSTextField自动调整它的字体大小以适合它的文本？

import Cocoa

class AutoFittingTextField: NSTextField {
    override func awakeFromNib() {
        super.awakeFromNib()
        self.isEditable = false
        self.isSelectable = false
        self.maximumNumberOfLines = 1
    }

    override func setStringValue(_ string: String) {
        super.setStringValue(string)
        adjustFontSize()
    }

    private func adjustFontSize() {
        let fontManager = NSFontManager.shared
        var fontSize = font?.pointSize ?? 12

        while fontManager.traitsOfFont(font!) != [] {
            fontSize -= 1
            font = fontManager.convert(font!, toSize: fontSize)
        }

        while fontManager.isMultiple(stringValue, forFont: font!) {
            fontSize += 1
            font = fontManager.convert(font!, toSize: fontSize)
        }
    }
}

import Cocoa

class AutoFittingTextField: NSTextField {
    override func awakeFromNib() {
        super.awakeFromNib()
        self.isEditable = false
        self.isSelectable = false
        self.maximumNumberOfLines = 1
    }

    override func setStringValue(_ string: String) {
        super.setStringValue(string)
        adjustFontSize()
    }

    private func adjustFontSize() {
        let layoutManager = NSLayoutManager()
        let textStorage = NSTextStorage(string: stringValue, attributes: [.font: font!])
        textStorage.addLayoutManager(layoutManager)

        var fontSize = font?.pointSize ?? 12
        let containerSize = bounds.size

        while layoutManager.usedRect(for: textContainer!).size.width > containerSize.width || layoutManager.usedRect(for: textContainer!).size.height > containerSize.height {
            fontSize -= 1
            font = font?.withSize(fontSize)
            textStorage.removeLayoutManager(layoutManager)
            textStorage.addLayoutManager(layoutManager)
        }
    }
}