ios - 来自 xib 的 addSubview - iOS 8 与 iOS 9

Question

这是我要添加的 viewController( View 在 .Xib 文件中)

class EmptyFeedViewController: UIViewController {
   @IBOutlet weak var view_center: UIView!
   @IBOutlet weak var img_icon: UIImageView!
   @IBOutlet weak var lbl_description: UILabel!

   override func viewDidLoad() {
      super.viewDidLoad()
      view.backgroundColor = UIColor.grayPale()
      lbl_description.textColor = UIColor.grayMeduim()
      lbl_description.text = "feed_empty".localizeFromFeedTable()
   }

   override func didReceiveMemoryWarning() {
      super.didReceiveMemoryWarning()
   }
}

我从另一个 viewController 中这样添加它

let placeholderVC = EmptyFeedViewController()
addChildViewController(placeholderVC)
view_placeholder = placeholderVC.view

在 iOS 9 上它工作正常但在 iOS 8 上“lbl_description”为 nil我应该如何为两个操作系统加载我的 View ？

Answer 1

由于您使用的是 Xibs，为了填充 IBOutlets，您应该使用指定的初始化程序创建 View Controller 的新实例 - initWithNibName:bundle:

let placeholderVC = EmptyFeedViewController(nibName: "EmptyFeedViewController",
                                             bundle: nil)