所有IBOutlets都是零

您好我正在使用以下代码初始化viewController：

var aboutUsViewController = self.storyboard?.instantiateViewControllerWithIdentifier("AboutUsViewController") as AboutUsViewController 

在此之后我转到aboutViewController 。 但是我在aboutViewController上的所有IBOutlets都是nil ！ 为什么？ 我正在使用MMDrawer库以获得侧栏菜单。

  var aboutUsViewController = self.storyboard?.instantiateViewControllerWithIdentifier("AboutUsViewController") as AboutUsViewController var aboutUsNavController = UINavigationController(rootViewController: aboutUsViewController) var appDelegate: AppDelegate = UIApplication.sharedApplication().delegate as AppDelegate appDelegate.centerContainer!.centerViewController = aboutUsNavController appDelegate.centerContainer!.toggleDrawerSide(MMDrawerSide.Left, animated: true, completion: nil) 

在侧栏上，我选择了关于我们的菜单项，在我创建AboutViewController并将其向左移动后…问题是当我初始化我的控制器时，出口是零

我在使用pageViewController时也遇到了这样的问题：

 class ViewController: UIViewController, UIPageViewControllerDataSource, UIPageViewControllerDelegate { let pageTitles = ["Title 1", "Title 2", "Title 3", "Title 4"] var images = ["long3","long4","long1","long2"] var count = 0 var pageViewController : UIPageViewController! override func viewDidLoad() { super.viewDidLoad() reset() // Do any additional setup after loading the view, typically from a nib. } override func didReceiveMemoryWarning() { super.didReceiveMemoryWarning() // Dispose of any resources that can be recreated. } func reset() { /* Getting the page View controller */ pageViewController = self.storyboard?.instantiateViewControllerWithIdentifier("PageViewController") as UIPageViewController self.pageViewController.dataSource = self let pageContentViewController = self.viewControllerAtIndex(0) self.pageViewController.setViewControllers([pageContentViewController!], direction: UIPageViewControllerNavigationDirection.Forward, animated: true, completion: nil) /* We are substracting 30 because we have a start again button whose height is 30*/ self.pageViewController.view.frame = CGRectMake(0, 0, self.view.frame.width, self.view.frame.height - 30) self.addChildViewController(pageViewController) self.view.addSubview(pageViewController.view) self.pageViewController.didMoveToParentViewController(self) } func pageViewController(pageViewController: UIPageViewController, viewControllerAfterViewController viewController: UIViewController) -> UIViewController? { var index = (viewController as PageContentViewController).pageIndex! index++ if (index >= self.images.count){ return nil } return self.viewControllerAtIndex(index) } func pageViewController(pageViewController: UIPageViewController, viewControllerBeforeViewController viewController: UIViewController) -> UIViewController? { var index = (viewController as PageContentViewController).pageIndex! if index UIViewController? { if((self.pageTitles.count == 0) || (index >= self.pageTitles.count)) { return nil } let pageContentViewController = self.storyboard?.instantiateViewControllerWithIdentifier("PageContentViewController") as PageContentViewController pageContentViewController.imageName = self.images[index] pageContentViewController.titleText = self.pageTitles[index] pageContentViewController.pageIndex = index return pageContentViewController } func presentationCountForPageViewController(pageViewController: UIPageViewController) -> Int { return pageTitles.count } func presentationIndexForPageViewController(pageViewController: UIPageViewController) -> Int { return 0 } } class PageContentViewController: UIPageViewController { @IBOutlet var imageViewMain: UIImageView! @IBOutlet var labelMain: UILabel! var pageIndex: Int! var titleText: String! var imageName: String! override func viewDidLoad() { super.viewDidLoad() self.imageViewMain.image = UIImage(named:imageName) self.labelMain.text = self.titleText self.labelMain.alpha = 0.1 UIView.animateWithDuration(1.0, animations:{ ()-> Void in self.labelMain.alpha = 1.0 }) // Do any additional setup after loading the view. } override func didReceiveMemoryWarning() { super.didReceiveMemoryWarning() // Dispose of any resources that can be recreated. } /* // MARK: - Navigation // In a storyboard-based application, you will often want to do a little preparation before navigation override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) { // Get the new view controller using segue.destinationViewController. // Pass the selected object to the new view controller. } */ } 

我有问题，标签和图像sockets是零！ 我使用MMDrawer库时遇到了同样的问题。 同样的情况。 我不是在使用segues！ 我认为因为那些网点是零

Answer 1

我假设您在实例化场景后立即查看出口（如果使用segues并尝试在prepareForSegue使用出口，您也会看到这种行为）。 但是直到你出现/推送到那个场景，视图被加载，并且调用viewDidLoad之后才会连接出口。

最重要的是，在调用viewDidLoad之前不要尝试使用sockets（即在实例化场景后不要立即使用sockets）。 而是将所需数据传递到目标场景（例如String属性），然后目标的viewDidLoad应填充sockets。

例如，您可能在AboutUsViewController有一个属性：

 var message: String! 

当您实例化AboutUsViewController ，您将设置该属性：

 let aboutUsViewController = self.storyboard?.instantiateViewControllerWithIdentifier("AboutUsViewController") as AboutUsViewController // use `as!` in Swift 1.2 aboutUsViewController.message = "some message" presentViewController(aboutUsViewController, animated: true, completion: nil) 

然后AboutUsViewController的viewDidLoad将使用该属性相应地填充sockets：

 override func viewDidLoad() { super.viewDidLoad() label1.text = message } 

但是你永远不会让原始视图控制器尝试设置/调整目标场景的出口。 这是AboutUsViewController的责任。

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只是为了确认，你的网点是否正确连接？ 下面显示了两种确认它们正确连接的方法。

当您在Interface Builder中选择视图控制器，然后查看连接检查器时，您是否看到您的sockets连接在那里？ 在以下快照中， label1已连接，但label2不是：

或者，当您查看代码并查看sockets时，您是否看到左边距中的实心点（意味着sockets已连接）或空点（意味着sockets未连接）？

Answer 2

您可以在演示之前使用此function，这在iOS9及更高版本中可用：

  aboutUsViewController.loadViewIfNeeded() 

Answer 3

我找到了答案。 我没有创建UIViewController，而是创建了UIPageViewController！