Demonstration of recomposition not occurring if the initial window list was empty

README.md

Relevant StackOverflow post

Main.kt

import androidx.compose.foundation.layout.*
import androidx.compose.material.*
import androidx.compose.runtime.*
import androidx.compose.ui.*
import androidx.compose.ui.window.*
import kotlinx.coroutines.*

data class SystemProfile(
    var name: String
)

private class MyWindowState(
    val title: String,
    val systemProfile: SystemProfile,
    private val close: (MyWindowState) -> Unit
) {
    fun close() = close(this)
}

private class MyApplicationState {
    val windows = mutableStateListOf<MyWindowState>()

    fun newWindow(systemProfile: SystemProfile) {
        windows.add(
            MyWindowState(
                title = "Blah title",
                systemProfile = systemProfile,
                close = windows::remove
            )
        )
    }
}

@Composable
fun SpxViewer(systemProfile: SystemProfile) {
    MaterialTheme {
        Surface(modifier = Modifier.fillMaxSize()) {
            Text("Details would go here.")
            Text("systemProfile = $systemProfile")
        }
    }
}

fun main() = application {
    val applicationState = remember { MyApplicationState() }

    LaunchedEffect(Unit) {
        // Simulate reading from file
        delay(2000)

        val systemProfile = SystemProfile(name = "Blah")
        applicationState.newWindow(systemProfile)
    }

    // After the first call, we never get here again, because adding a window
    // to the list doesn't trigger recomposition.
    for (window in applicationState.windows) {
        key(window) {
            Window(onCloseRequest = window::close, title = window.title) {
                SpxViewer(window.systemProfile)
            }
        }
    }
}