Flattening Flow: FlatMapLatest or FlattenLatest

What it does

Here when an emission has happened and before it is consumed if another emission happens, The previous emission is canceled and new emission is used

Output

<Emitted> -->0
<Emitted> -->1
collected: ---> Current string no -->0 at the threadDefaultDispatcher-worker-4
<Emitted> -->2
<Emitted> -->3
collected: ---> Current string no -->1 at the threadDefaultDispatcher-worker-4
<Emitted> -->4
collected: ---> Current string no -->2 at the threadDefaultDispatcher-worker-4
collected: ---> Current string no -->3 at the threadDefaultDispatcher-worker-4
collected: ---> Current string no -->4 at the threadDefaultDispatcher-worker-4

Code

class FlattenFlowsDemoVm @Inject constructor(
    @ApplicationContext private val context: Context,
) : ViewModel() {

    private val rootScope = CoroutineScope(context = Dispatchers.IO)

    /**
     * Flow of integers
     */
    fun generateIntegers() = flow {
        repeat(100){
            delay(1000)
            emit(it)
        }
    }


    /**
     * Generate a flow of strings
     */
    fun generateFlowOfStrings(value : Int) = flow {
        val content = "Current string no -->$value at the thread${Thread.currentThread().name}"
        println("<Emitted> -->$value")
        emit(content)
    }



    fun flatMaplatest() = rootScope.launch(CoroutineName("flatMapLatest")){
        generateIntegers()
            .take(5)
            .flatMapLatest {
                generateFlowOfStrings(it)
            }.collect{
                delay(2000)
                println("collected: ---> $it")
            }
    }

}