I need something to run each time the window gains...

# compose

[Mark]

I need something to run each time the window gains focus but I notice that the first time the screen is shown WindowInfo.isWindowFocused remains false. Only when switching away from the app and returning, does this property become true. I also noticed someone else reported this a few years ago: https://issuetracker.google.com/issues/186226793 (Android)

[Mark]

My workaround

@Composable
fun WindowFocusObserver(onWindowFocusChanged: (isWindowFocused: Boolean) -> Unit) {
    val isWindowFocused = LocalWindowInfo.current.isWindowFocused
    var isFirstTime by remember {
        mutableStateOf(true)
    }
    val callback = rememberUpdatedState(onWindowFocusChanged)
    LaunchedEffect(isWindowFocused || isFirstTime) {
        // note: cannot change isFirstTime in snapshotFlow so change here instead
        val overrideValue = isFirstTime
        isFirstTime = false
        snapshotFlow { isWindowFocused || overrideValue }.collect { callback.value(it) }
    }
}