API for creating a parent job backed by a coroutineContext

I want to create a job parent for cancellation purposes. I want the parent job to run in a specific context. Currently, we have to do it this way:

private val jobParent = Job().apply { this + CommonPool }

I think passing that information into the constructor would make for a better and more obvious api.

private val jobParent = Job(CommonPool)

Is something like this possible?

Rest of usage:

launch(parentJob) {  ... }

override fun onCleared() {
        jobParent.cancelChildren()
    }  
}

[DrewCarlson]

val job = Job().apply { this + dispatcher }

The plus operator for CoroutineContext returns a new CombinedContext, it does not modify the Job.

I think this is what you are looking for:

val dispatcher = newSingleThreadContext("MyDispatcher")
val context = Job() + dispatcher
        
launch(context) {
  log(1)
}

Job.kt contains two extension functions for CoroutineContext that allow for cancelling the Job in this new context.

[ZakTaccardi]

the use case for this is creating a parent job for children to automatically have a dispatcher applied. I was under the impression this could be done, but I don’t think it can.

val dispatcher = newSingleThreadContext("MyDispatcher")
val job = Job().apply { this + dispatcher }
        
launch(parent = job) {
  log(1)
}

I thought the coroutine would be dispatched by the dispatcher above, but it’s actually the DefaultDispatcher.