检查函数是否被调用？

Question

我将如何去检查一个函数是否被调用？我创建了一个功能，看是否水平完成，像这样：

func levelOneCompleted(){ 

} 

当一个水平打，我叫（）levelOneCompleted功能。

现场然后去另一个场景。在这个场景中，我想检查函数是否被调用。我想我可以做出某种“如果陈述”。

if levelOneCompleted is called { 
//do this 

else{ 

//do this 
} 

这样做的最好方法是什么？

Answer 1

设置一个布尔标志，true内levelOneCompleted()：

var isLevelOneCompleted = false 

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

后来......

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

Answer 2

斯威夫特3 &的Xcode 8.3.2

有2招做到这一点，这里是代码：

// 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 
}