I'm working on an Android app, and in my VM I have an init {} block with 3 separate "inifinite" collect {} calls. viewModelScope.launch { launch { service.flow1().collect { } } launch { service.flow2(NEED an id FROM flow 1).collect { } } launch { service.flow3(NEED an id FROM flow 1).collect { } } } What would be the best way to do something like that?

is your intention something along these lines?

service.flow1().mapLatest { id ->
    coroutineScope {
        service.flow2(id).launchIn(this)
        service.flow3(id).launchIn(this)
    }
}.buffer(0).launchIn(viewModelScope)

which will re-start

flow2

,

flow3

with each

id

from

flow1

. (or else what do you expect to happen before an

id

is available, or after a new value arrives?)

hm. its close. My "issue" is that flow1() will called a bunch, but the id I need will likely never change, but I need that id first so I can call flow2 and flow3, but flow1 still needs to do a bunch of work. I think a really simple (but inefficient solution to my problem would be this.

viewModelScope.launch {
    val initialValue = service.flow1().first().someProperty
    launch { service.flow1().collect { //update UI with changes } }
    launch { service.flow2(initialValue).collect { //update UI with changes} }
    launch { service.flow3(initialValue).collect { //update UI with changes} }
}

you can convert your

flow

into a shared flow after you map it to the

id

, then use that shared flow to drive your

flow2

and

flow3

, something like this

val idFlow = flow1.map { value ->
            // do whatever processing you need with value here
            value.id
        }.distinctUntilChanged()
            .shareIn(viewModelScope, SharingStarted.Eagerly)

        idFlow.flatMapLatest { id ->
            flow2(id)
        }.onEach { value -> 
            // handle value
        }.launchIn(viewModelScope)

        idFlow.flatMapLatest { id ->
            flow3(id)
        }.onEach { value ->
            // handle value
        }.launchIn(viewModelScope)

oh boy. okay. lots of new apis there and kinda going over my head, but im going to try to learn some more of these starting tomorrow. thanks all