Compose Multiplatform Lifecycle Tracker

A library to track the lifecycle of the application in Compose Multiplatform.

Setup

To use this library, you need some setup in your project.

Android

This library uses the androidx.lifecycle:lifecycle-runtime-ktx library to track the lifecycle of the page. You need to add the following dependency to your build.gradle.kts file.

val androidMain by getting {
   dependencies {
      implementation ("androidx.lifecycle:lifecycle-runtime-ktx:2.7.0")
   }
}

Then, you need to add the AndroidLifecycleEventObserver to your Activity or Fragment to track the lifecycle of the page and provide the LifecycleTracker to the App using CompositionLocalProvider.

class MainActivity : AppCompatActivity() {
    private val lifecycleTracker = LifecycleTracker()
    private val observer = AndroidLifecycleEventObserver(lifecycleTracker)

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        lifecycle.addObserver(observer)

        setContent {
            CompositionLocalProvider(LocalLifecycleTracker provides lifecycleTracker) {
                MainView()
            }
        }
    }

    override fun onDestroy() {
        super.onDestroy()
        lifecycle.removeObserver(observer)
    }
}

iOS

For iOS, you need to set the 'LifecycleComposeUIVCDelegate' as the delegate of the UIComposeViewController to track the lifecycle of the page and provide the LifecycleTracker to the App using CompositionLocalProvider.

fun MainViewController(): UIViewController {
    val lifecycleTracker = LifecycleTracker()
    return ComposeUIViewController({
        delegate = LifecycleComposeUIVCDelegate(lifecycleTracker)
    }) {
        CompositionLocalProvider(LocalLifecycleTracker provides lifecycleTracker) {
            App()
        }
    }
}

Usage

The usage is quite simple, you just need to create a 'LifecycleListener' and add it to the LifecycleTracker.

@Composable
private fun LifecycleTest() {
    val lifecycleTracker = LocalLifecycleTracker.current
    DisposableEffect(Unit) {
        val listener =
            object : LifecycleObserver {
                override fun onEvent(event: LifecycleEvent) {
                    println("Lifecycle: onEvent: $event")
                }
            }
        lifecycleTracker.addObserver(listener)
        onDispose {
            lifecycleTracker.removeObserver(listener)
        }
    }
}

Download

This library is available on Maven Central. You can add it to your project by adding the following dependency to your build.gradle.kts file.

repositories {
    mavenCentral()
}

kotlin {
    sourceSets {
        commonMain {
            dependencies {
              api("io.github.kevinnzou:compose-multiplatform-lifecycle-tracker:1.0.0")
            }
        }
    }
}