Hi! Does anyone know why job2() is not running? Am...

# android

[Tin Tran]

Hi! Does anyone know why job2() is not running? Am I doing something wrong?

class MyViewModel:ViewModel() {
   private val job = SupervisorJob()
   private val scope = CoroutineScope(<http://Dispatcher.IO|Dispatcher.IO> + job)

   fun test() {
       viewModelScope.launch {
           job1()
           job.cancelAndJoin()
           scope.launch {
               job2()
           }
      }
  }
}

[Johannes Doll]

Hey, I’m not 100% sure, it has been a while since I used Coroutines extensively, but:

I’m pretty sure it’s because you cancel the parent job (the one you pass to CoroutineScope) of the job you launch afterwards (the one containing job2()). Does it work if you remove the job.cancelAndJoin() line?

[Tin Tran]

Yes it does. But I want to cancel jobs previously launched by that coroutine scope. What should I do in that case?

[Johannes Doll]

I guess you could either keep a reference to the job directly or cancel the scope and replace it with a new one for your new job.

[Johannes Doll]

Once canceled a scope is no longer active and you can not make it active again (as far as I know)

[Joost Klitsie]

can you try cancelChildren?

[Joost Klitsie]

on the job

[Johannes Doll]

@Joost Klitsie I didn’t know that one, thx
And I guess that should work

[Tin Tran]

cancelChildren works perfect. Thank you Joost and Johannes

[Joost Klitsie]

@Johannes Doll cancelchildren only works for supervisorjob, not the regular job, perhaps that is why 🙂 the power of supervisorjob is that it doesn't cancel if children get cancelled, as well as you can cancel the children