NSParagraphStyle中的paragraphSpacingBefore导致插入符号位于UITextView

Question

当我在paragraphSpacingBefore中分配NSMutableParagraphStyle属性时，UITextView的插入符号在输入时位于文本上方。我该如何解决这个问题？

func something() -> NSMutableParagraphStyle {

    let paraStyle = NSMutableParagraphStyle()
    paraStyle.paragraphSpacing = quoteParagraphSpacing
    paraStyle.lineSpacing = 10

    paraStyle.paragraphSpacingBefore = 20
    paraStyle.alignment = .left
    return paraStyle

}

此功能就像这样使用。

textView.typingAttributes = [NSAttributedStringKey.paragraphStyle.rawValue: something(), ....]

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