Hi guys! There are scopes, like

ViewModelScope

from

AAC

, which works best for most of simple use cases, but when you want to cancel the job whose lifecycle is very specific, then there is a place for discussion. Suppose an operation should be run starting from

onStart()

call until there is a

onStop()

call. What would you suggest as good practice here to control this operation’s lifecycle? I started by creating custom scope, inside which this operation would run, then i realised, that after cancellation this scope can’t be re-used. Then I thought that creating a new scope every time

onStart()

is called is a bad idea (or not?). So I switched to a nullable variable holding a reference to a

Job

created after

launch { ... }

in

onStart()

, which I cancel in

onStop()

. Seems normal, but what if you want to cancel a lot of different jobs between `onStart()`/()`onStop()` calls? I might want a strange thing to do: having a scope, which, when you cancel it, cancel all its children job, but could be reset to allow new coroutines to run. Perhaps, I do not understand properly which logic stands behind not allowing to re-use cancelled scope. Thanks!

Simplest solution is what you said:

lifecycleScope.launch {}

a bunch of `Job`s in

onStart

and cancel them in

onStop

. To keep track of all jobs at once, just use a class property

private val jobs = mutableListOf<Job>()

and simply add jobs to it:

jobs += lifecycleScope.launch {}

. in

onStop

just

jobs.forEach { it.cancel() }

(which could be a nice extension on

Collection<Job>

)