JarCastingFlowRedux
Building async. running Kotlin Multiplatform state machine made easy with a DSL and coroutines.
Usage
Full documentation and best bractices can be found here: https://freeletics.github.io/FlowRedux/
sealed class State
object LoadingState : State()
data class ContentState(val items : List<Item>) : State()
data class ErrorState(val error : Throwable) : State()
sealed class Action
object RetryLoadingAction : Action()
class MyStateMachine : FlowReduxStateMachine<State, Action>(LoadingState){
init {
spec {
inState<LoadingState> {
onEnter { stateSnapshot : LoadingState ->
// executes this block whenever we enter LoadingState
try {
val items = loadItems() // suspending function / coroutine to load items
OverrideState( ContentState(items) ) // Transition to ContentState
} catch (t : Throwable) {
OverrideState( ErrorState(t) ) // Transition to ErrorState
}
}
}
inState<ErrorState> {
on<RetryLoadingAction> { action : RetryLoadingAction, stateSnapshot : ErrorState ->
// executes this block whenever ErrorState is current state and RetryLoadingAction is emitted
OverrideState( LoadingState ) // Transition to LoadingState which loads list again
}
}
inState<ContentState> {
collectWhileInState( flowOf(1,2,3) ) { value : Int, stateSnapshot : ContentState ->
// observes the given flow as long as state is ContentState.
// Once state is changed to another state the flow will automatically
// stop emitting.
MutateState<ContentState, State> {
copy( items = this.items + Item("New item $value"))
}
}
}
}
}
}
val statemachine = MyStateMachine()
launch { // Launch a coroutine
statemachine.state.collect { state ->
// do something with new state like update UI
renderUI(state)
}
}
// emit an Action
launch { // Launch a coroutine
statemachine.dispatch(Action)
}
In an Android Application you could use it with AndroidX ViewModel like that:
class MyViewModel @Inject constructor(private val stateMachine : StateMachine) : ViewModel() {
val state = MutableLiveData<State>()
init {
viewModelScope.launch { // automatically canceled once ViewModel lifecycle reached destroyed.
stateMachine.state.collect { newState ->
state.value = newState
}
}
}
fun dispatch(action : Action) {
viewModelScope.launch {
stateMachine.dispatch(action)
}
}
}
Dependencies
There are two artifacts that you can include as dependency::
flowredux: this is the core library. Usually you dont want to use the core library directly but rather use thedsl.dslwhich provides a convenient DSL on top of the core library. Usually this is what you want.
Multiplatform
implementation 'com.freeletics.flowredux:flowredux:0.5.0'
implementation 'com.freeletics.flowredux:dsl:0.5.0'
JVM only
implementation 'com.freeletics.flowredux:flowredux-jvm:0.5.0'
implementation 'com.freeletics.flowredux:dsl-jvm:0.5.0'
Native binaries
implementation 'com.freeletics.flowredux:flowredux-iosx64:0.5.0'
implementation 'com.freeletics.flowredux:flowredux-iosarm64:0.5.0'
implementation 'com.freeletics.flowredux:flowredux-iosarm32:0.5.0'
implementation 'com.freeletics.flowredux:flowredux-watchosx86:0.5.0'
implementation 'com.freeletics.flowredux:flowredux-watchosarm64:0.5.0'
implementation 'com.freeletics.flowredux:flowredux-watchosarm32:0.5.0'
implementation 'com.freeletics.flowredux:flowredux-tvosx64:0.5.0'
implementation 'com.freeletics.flowredux:flowredux-tvosxarm64:0.5.0'
implementation 'com.freeletics.flowredux:dsl-iosx64:0.5.0'
implementation 'com.freeletics.flowredux:dsl-iosarm64:0.5.0'
implementation 'com.freeletics.flowredux:dsl-iosarm32:0.5.0'
implementation 'com.freeletics.flowredux:dsl-watchosx86:0.5.0'
implementation 'com.freeletics.flowredux:dsl-watchosarm64:0.5.0'
implementation 'com.freeletics.flowredux:dsl-watchosarm32:0.5.0'
implementation 'com.freeletics.flowredux:dsl-tvosx64:0.5.0'
implementation 'com.freeletics.flowredux:dsl-tvosxarm64:0.5.0'
JavaScript
No javascript version release yet but its on our TODO list.
Snapshot
Latest snapshot (directly published from master branch from Travis CI):
allprojects {
repositories {
// Your repositories.
// ...
// Add url to snapshot repository
maven {
url "https://oss.sonatype.org/content/repositories/snapshots/"
}
}
}
Then just use -SNAPSHOTsuffix as version like
implementation 'com.freeletics.flowredux:dsl:0.5.1-SNAPSHOT'
