Android Kotlin Flows

Introduction

This is a page to capture anything important about kotlin flows. This very similar to RxJava

Simple Example

Note this code would not be executed, if there are no subscribers like RxJava

 
  val countDownFlow = flow<Int> {
    val startingValue = 10
    var currentValue = startingValue
    emit(currentValue)
    while (currentValue > 0) {
      delay(1000L)
      currentValue--
      emit(currentValue)
    }
  }

We can log our emits in the ViewModel to debug with

 
    init {
        collectFlow()
    }

    private fun collectFlow() {
        viewModelScope.launch {
            countDownFlow.collect { time ->
                println("Time remaining: $time")
            }
        }
    }

We can use collectLatest which will only output the latest state