Coroutines artifact

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• TOC

This page contains information about kstatemachine-coroutines artifact functionality. Which contains the library APIs for working in Kotlin Coroutines environment.

This artifact depends on Kotlin Coroutines library

You can find common information about multithreading library usage and coroutines on multithreading page

Artifact separation

KStateMachine has first class support of coroutines. Even if you don’t use Kotlin Coroutines and kstatemachine-coroutines artifact all library callbacks are suspendable functions. So the functionality of this module should not be treated as “wrappers” or “extensions”. This is just a core functionality which is separated from original kstatemachine artifact to fallow language architecture regarding coroutines support.

Contains additional functions to work with KStateMachine depending on Kotlin Coroutines library

State machine creation

The artifact contains createStateMachine() / createStateMachineBlocking() methods, which were described in Create state machine block

Flow notifications

Coroutines users often use Flow to get some changes from a source. The library provides StateMachine extension methods which represents notification APIs (listeners) in a form of Flow:

• stateMachineNotificationFlow() returns a SharedFlow of all machine notifications:

 machine.stateMachineNotificationFlow().collect {
    when (it) {
        is Started -> println("Started ${it.machine}")
        is TransitionTriggered -> println("TransitionTriggered ${it.transitionParams.event}")
        is TransitionComplete -> println("TransitionComplete ${it.transitionParams.event}")
        is StateEntry -> println("StateEntry ${it.state}")
        is StateExit -> println("StateExit ${it.state}")
        is StateFinished -> println("StateFinished ${it.state}")
        is Stopped -> println("Stopped ${it.machine}")
        is Destroyed -> println("Destroyed ${it.machine}")
    }
}

• activeStatesFlow() returns a StateFlow of active machine states:

machine.activeStatesFlow().collect { activeStates ->
    println("The set of active states: $activeStates")
}

Event processing

processEventByLaunch() and processEventByAsync() functions are described in event processing block. You can use them to process events in asynchronous way.