iOS11中导航栏中的大型标题的多行

是否有可能让iOS 11中导航栏的新大标题显示多行？App Store应用程序执行此操作但我在当前文档中找不到任何内容来执行此操作.标准行为只显示带有省略号的一行,如果它太长.

将以下代码添加到viewWillAppear中：

    navigationController?.navigationBar.prefersLargeTitles = true
    self.navigationController?.navigationItem.largeTitleDisplayMode = .automatic

    self.title = "Hello big text, For navigation large style bar"
    navigationController?.navigationBar.largeTitleTextAttributes = [NSAttributedStringKey.foregroundColor: UIColor.black, NSAttributedStringKey.font : UIFont.preferredFont(forTextStyle: .largeTitle)]

    var count = 0
    for item in(self.navigationController?.navigationBar.subviews)! {
        for sub in item.subviews{
            if sub is UILabel{
                if count == 1 {
                    break;
                }
                let titleLab :UILabel = sub as! UILabel
                titleLab.numberOfLines = 0
                titleLab.text = self.title
                titleLab.lineBreakMode = .byWordWrapping
                count = count + 1
            }
        }

    }
    self.navigationController?.navigationBar.layoutSubviews()
    self.navigationController?.navigationBar.layoutIfNeeded()

后退按钮面临的问题将很快更新。