iOS 11導航欄中大標題的多行顯示11

Question

iOS 11中導航欄的新大標題顯示多行是否可能？ App Store應用程序執行此操作，但在當前文檔中找不到任何內容來執行此操作。如果標準行爲太長，則只顯示一行帶省略號的行。

Answer 1

添加以下代碼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() 

面對與後退按鈕將很快更新問題..