ListenAnimationDemo.kt

Column {
    var flag by remember { mutableStateOf(false) }
    val transition = updateTransition(targetState = flag, label = "My Animation")
    // Method #1
    LaunchedEffect(transition.currentState == transition.targetState) {
        if (transition.currentState == transition.targetState) {
            println("Animation finished (1)")
        }
    }
    // Method #2
    LaunchedEffect(Unit){
        snapshotFlow { transition.currentState == transition.targetState }
            .filter { it }
            .collect {
                println("Animation finished: (2)")
            }
    }
    transition.AnimatedVisibility(
        visible = { it },
        enter = fadeIn(animationSpec = tween(3000)),
        exit = fadeOut(animationSpec = tween(3000)),
    ) {
        Box(
            modifier = Modifier
                .size(100.dp)
                .background(Color.Red),
            contentAlignment = Alignment.Center
        ) {
            Text(text = "I am content")
        }
    }
    Button(onClick = { flag = !flag }) {
        Text(text = "Toggle")
    }
}