Synchronization in execution of methods of a class using co-routines.

Questions & Answers
1

I have a Class which has a method “ExecuteSync”.
The code snippet of the class containing the function is as follows:

public class MyTasksClass : Monobehaviour{

    public void ExecuteSync(string actionName){

switch(actionName){
	
	case "action1" :
        	StartCoroutine(ActionOne());
		
	break;
	
	case "action2" :
		StartCoroutine(ActionTwo());
	break;
	
}

}


IEnumerator ActionOne(){
	Debug.Log("Action One Started");
	int a = 0;
	while(a<100){
		yield return null;
	}
	Debug.Log("Action One Ended");
	yield return null;
}

//Please note that these two methods are not related to one another.
IEnumerator ActionTwo(){
	Debug.Log("Action Two Started");
	int a = 500;
	while(a<1000){
		yield return null;
	}
	Debug.Log("Action Two Ended");
	yield return null;
}

}

There is another class UIController from which we can call these methods like as follows:

public class UIController : Monobehaviour{

   public MyTasksClass myTaskClass;

   void Start(){
	myTaskClass = FindObjectOfType<MyTasksClass>();
	
	Debug.Log("Synchronous started");
	myTaskClass.ExecuteSync(action1);
	Debug.Log("Synchronous ended");
   }

 }

The expected output should print in this order:

Synchronous started
Action One Started
Action One Ended
Synchronous ended

But the actual output is as follows:

Synchronous started
Synchronous ended
Action One Started
Action One Ended

Is there any way to make it work in a Synchronous way to print the expected output ? Any help will be appreciated.

2

Well that’s exactly how people would expect Coroutines to work.

Coroutines wont just stop your “Start” method for the frames they need to finish, that’s just not how it works.

I would recommend to just keep all that logic in a separate function that handles what happens “after” the coroutine end, stay out of the “start” method.

 IEnumerator ActionOne(){
     Debug.Log("Action One Started");
     int a = 0;
     while(a<100){
         yield return null;
     }
    CoroutineEnded("Action One Ended");
     yield return null;
 }
 
 //Please note that these two methods are not related to one another.
 IEnumerator ActionTwo(){
     Debug.Log("Action Two Started");
     int a = 500;
     while(a<1000){
         yield return null;
     }
     CoroutineEnded("Action Two Ended");
     yield return null;
 }

public void CoroutineEnded(string msg){
    Debug.Log(msg);
}