AHTabBarController與Swift不兼容

Question

我想在swift項目中使用「AHTabBarController」。

我不知道爲什麼這個代碼不工作：

 var tabBarController = self.window?.rootViewController as AHTabBarController 

     var tab1 = AHTabView() 
     tab1.image = UIImage(named: "") 
     tab1.title = "Tab 1" 

     var tab1_subItem = AHSubitemView(frame: UIScreen.mainScreen().bounds) 
     tab1_subItem.image = UIImage(named: "") 
     tab1_subItem.title = "Tab 1 Title" 
     tab1_subItem.viewControllerIdentifier = "channelsListSB" 

     tab1.addSubitem(tab1_subItem) 


     tabBarController.tabs.addObjectsFromArray([tab1]) 

     self.window?.rootViewController = tabBarController 

Objective-C的代碼是：

AHTabBarController *tabBarController = (AHTabBarController*)self.window.rootViewController; 

/******* PURUS *******/ 
AHTabView *purus = [AHTabView new]; 
[purus setImage:[UIImage imageNamed:@"persondot"]]; 
[purus setTitle:@"Purus"]; 

AHSubitemView *pFirst = [AHSubitemView new]; 
[pFirst setImage:[UIImage imageNamed:@"persondot"]]; 
[pFirst setTitle:@"First"]; 
[pFirst setViewControllerIdentifier:@"PurusFirst"]; 
[purus addSubitem:pFirst]; 

// … 

AHSubitemView *fFirst = [AHSubitemView new]; 
[fFirst setImage:[UIImage imageNamed:@"photos"]]; 
[fFirst setTitle:@"First"]; 
[fFirst setViewControllerIdentifier:@"FringillaFirst"]; 
[fringilla addSubitem:fFirst]; 
//Don't forget to add your AHTabView instances to the AHTabBarController! 
[tabBarController.tabs addObjectsFromArray:@[purus, fringilla, ipsum]]; 

的錯誤是：

fatal error: unexpectedly found nil while unwrapping an Optional value

Answer 1

你不要指定一條線，所以我只是猜測問題在這裏：

tab1.image = UIImage(named: "") 

這是返回nil，但您將它分配給image，這是一個隱式解包可選。您需要指定一個確保返回圖像的實際圖像名稱。或者，你可以有條件地這樣做：

if let image = UIImage(named: "") { 
    tab1.image = image 
} else { 
    // handle failure 
}