Why is ViewModelScoped coroutine unusable after ViewModel onCleared() method called

Question

I am sharing an ActivityScoped viewModel between multiple Fragments in my current Android application.

The viewModel employs Coroutine Scope viewModelScope.launch{}

My issue is the .launch{} only works until the owning ViewModel onCleared() method is called.

Is this how ViewModel scoped coroutines are supposed to work?

Is there an approach I can use to "Reset" the viewModelScope so that .launch{} works following the onCleared() method being called?

heres my code::

Fragment

RxSearchView.queryTextChangeEvents(search)
        .doOnSubscribe {
            compositeDisposable.add(it)
        }
        .throttleLast(300, TimeUnit.MILLISECONDS)
        .debounce(300, TimeUnit.MILLISECONDS)
        .map { event -> event.queryText().toString() }
        .observeOn(AndroidSchedulers.mainThread())
        .subscribe { charactersResponse ->
            launch {
                viewModel.search(charactersResponse.trim())
            }
        }

. . .

override fun onDetach() {
    super.onDetach()
    viewModel.cancelSearch()
    compositeDisposable.clear()
}

ViewModel

suspend fun search(searchString: String) {
    cancelSearch()

    if (TextUtils.isEmpty(searchString)) {
        return
    }

    job = viewModelScope.launch {
        repository.search(searchString)
    }
}

fun cancelSearch() {
    job?.cancelChildren()
}

. . .

override fun onCleared() {
    super.onCleared()
    repository.onCleared()
 }

What am I doing wrong?

UPDATE

If I amend my launch code to this

job = GlobalScope.launch {
    repository.search(searchString)
}

It solves my issue, however is this the only way to achieve my desired result?

I was under the impression GlobalScope was "Bad"

Answer 1

following a cal to onCleared() my viewModelScoped cororoutine Launch stops executing

That's a feature, not a bug.

Once the ViewModel is cleared, you should not be doing anything in that ViewModel or whatever its LifecycleOwner was. All of that is now defunct and should no longer be used.

however is this the only way to achieve my desired result?

The correct solution is to get rid of the code from the ViewModel. If you are expecting some background work to go past the lifetime of an activity or fragment, then that code does not belong in the activity/fragment or its associated viewmodels. It belongs in something that has a matching lifetime to the work that you are trying to do.