Anyone else find the naming of `lifecycleScope.lau...

# android

[Orhan Tozan]

Anyone else find the naming of lifecycleScope.launchWhenStarted {} misleading?

lifecycleScope.launch { ... } -> launches the coroutine immediatly, gets canceled when lifecycle is destroyed.
Now I would expect lifecycleScope.launchWhenStarted { ... } to behave the same as the above, except it being different in the timing of the coroutine launching: coroutine gets launched when the lifecycle is started, and gets canceled when lifecycle is destroyed.
But what it actually does, is also suspend the coroutine after it is launched, when the lifecycle is stopped.

Maybe I've misunderstood it, but if not, I think a more fitting name would be something like lifecycleScope.runWhileStarted {...} ? Or maybe perhaps a whole new scope? (lifecycleStartedScope ), It feels like these launchWhen methods try to emulate sub-coroutinescopes that could be replaced by introducing new lifecyclescopes that are different instances of CoroutineScope, an API that exists for handling the lifecycles of coroutines.

Curious to hear your thoughts about this.

[ephemient]

I don't find it as confusing in Lifecycle.whenStarted(...), but I do agree about LifecycleCoroutineScope method naming

[Adam Powell]

I agree with OP, I argued for the described expected behavior and lost 🙂 to this day I still use my own variants that behave closer to that way instead

[Adam Powell]

the pausing dispatcher causes bugs and holds onto memory for much longer than it should, since cancelled coroutines can't resume with their CancellationExceptions until the associated lifecycle becomes started again

[Adam Powell]

the extensions I use instead launch on the described "up" lifecycle event, cancel on the respective "down" event (e.g. start/stop are paired) and re-launch when the associated up event is encountered again

[dave08]

Could you maybe make a gist of them if they're shareable @Adam Powell? It could help a bunch of us 🙂 !

[flosch]

https://github.com/floschu/loco does it that way

[Jan Skrasek]

missing dispatcher also brings problem that we can't use Flow.launchIn.

[Adam Powell]

@dave08 https://gist.github.com/adamp/835197329b2383b6e0752f6629bd09b4

[Orhan Tozan]

Good discussion guys. Side question: In a Fragment , is it better to call the lifescopeScope.launchWhenStarted {} / .addLiveLauncher methods in onCreate or onViewCreated ?