[Swift]ViewController中xib控制元件為空
阿新 • • 發佈：2018-10-31
在ViewController的xib中定義了一些控制元件，然後在使用的時候會因為這個控制元件為空而崩潰，報錯為：
解決辦法如下：
1.首先要保證正確初始化了ViewController，使用初始化方法init(nibName nibNameOrNil:String?, bundle nibBundleOrNil:NSBundle?) 初始化檢視控制器（OC中對應 -(
2.在viewDidLoad方法載入之前，這些xib的控制元件是可能為空的，所以在變數的屬性觀察器中使用xib控制元件時要注意。如：
應當在viewDidLoad之後使用這些控制元件。
Swift Error fatal error: unexpectedly found nil while unwrapping an Optional value解決辦法如下：
1.首先要保證正確初始化了ViewController，使用初始化方法init(nibName nibNameOrNil:String?, bundle nibBundleOrNil:NSBundle?) 初始化檢視控制器（OC中對應 -(
|
/* The designated initializer. If you subclass UIViewController, you must call the super implementation of this method, even if you aren't using a NIB. (As a convenience, the default init method will do this for you, and specify nil for both of this methods arguments.) In the specified NIB, the File's Owner proxy should have its class set to your view controller subclass, with the view outlet connected to the main view. If you invoke this method with a nil nib name, then this class' -loadView method will attempt to load a NIB whose name is the same as your view controller's class. If no such NIB in fact exists then you must either call -setView: before -view is invoked, or override the -loadView method to set up your views programatically. */ |
2.在viewDidLoad方法載入之前，這些xib的控制元件是可能為空的，所以在變數的屬性觀察器中使用xib控制元件時要注意。如：
|
varnaviTitle :String?{ naviView.title = naviTitle } } |