I have like `2 flows` and I want to observe their changes with `flatMapLatest`, if either of them em...

# android

[Vivek Sharma]

I have like 2 flows and I want to observe their changes with flatMapLatest, if either of them emit new value, I want to trigger some action, but how can I observe on 2 flows , should I combine them ? how can I do it

[okarm]

Yes, combine.
https://kotlin.github.io/kotlinx.coroutines/kotlinx-coroutines-core/kotlinx.coroutines.flow/combine.html

For 2 flows you can use either of the following forms:

Top level function

combine(f1, f2) { v1, v2 -> TODO() }

Flow.combine extension

f1.combine(f2) { v1, v2 -> TODO() }

[Vivek Sharma]

when I was using flatMapLatest  and inside lambda, I was receiving flow and flatMapLatest  was returning that flow,
but when I use combine, this will emit Flow<Flow<>> , so is there a way to achieve like flatMapLatest

[Vivek Sharma]

val someStateFlow = flow1.combine(flow2) { a, b ->
    recievingFlowFromRepository()
}.stateIn(...)

[Vivek Sharma]

I have code like this ,so this returns Flow<Flow<>> because combine returns by making a flow inside a lambda

[okarm]

Yes

paramFlow1.combine(paramFlow2) { a, b ->
    Pair(a, b)
}.flatMapLatest { (a, b) -> // destructured Pair
    loadWithParameters(a, b) // this returns a Flow
}.stateIn(...)

[Vivek Sharma]

thanks for the quick tip