檢查函數是否被調用？

Question

我將如何去檢查一個函數是否被調用？我創建了一個功能，看是否水平完成，像這樣：

func levelOneCompleted(){ 

} 

當一個水平打，我叫（）levelOneCompleted功能。

現場然後去另一個場景。在這個場景中，我想檢查函數是否被調用。我想我可以做出某種「如果陳述」。

if levelOneCompleted is called { 
//do this 

else{ 

//do this 
} 

這樣做的最好方法是什麼？

Answer 1

設置一個布爾標誌，true內levelOneCompleted()：

var isLevelOneCompleted = false 

func levelOneCompleted(){ 
    // do things... 
    isLevelOneCompleted = true 
} 

後來......

if isLevelOneCompleted { 
    //do this 
} else { 
    //do this 
} 

Answer 2

斯威夫特3 &的Xcode 8.3.2

有2招做到這一點，這裏是代碼：

// Async operation 
func levelOneCompleted(completion: (_ completed: Bool) -> Void) { 
    // do your function here 
    completion(true) 
} 

// Here is how to use it 
// than u can declare this in viewDidLoad or viewDidAppear, everywhere you name it 
override func viewDidAppear(_ animated: Bool) { 
    super.viewDidAppear(animated) 

    // this is async operation 
    levelOneCompleted { (completed) in 
     if completed { 
      print("levelOneCompleted is complete") 
      // do something if levelOneCompleted is complete 

      DispatchQueue.main.async { 
       // Update your UI 
      } 
     } else { 
      print("levelOneCompleted is not completee") 
      // do something if levelOneCompleted is not complete 

      DispatchQueue.main.async { 
       // Update your UI or show an alert 
      } 
     } 
    } 
} 


// Or u can use this code too, and this is Sync operation 
var isLevelTwoCompleted: Bool = false 
func levelOneCompleted() { 
    // do your function here 
    isLevelTwoCompleted = true 
} 


// to check it u can put this function everywhere you need it 
if isLevelTwoCompleted { 
    //do something if level two is complete 
} else { 
    //do something if level two is not complete 
}