mutableStateOf holding the value after the recomposition without remember API in Jetpack Compose

Question

Any time a state is updated a recomposition takes place.

but here, I haven't used the remember API, but after the recomposition also it's holding the value, is the mutableStateOf() will remember the value without remember API?

@Composable
fun MyChildUI() {

    var count by mutableStateOf(1)

    Button(onClick = {
        count++
        println(count)
    }) {
        Text(text = "$count")
    }
}

Answer 1

In this particular example when you click the button, only lines 42-47 will be recomposed. You can verify this by adding a log statement in line 41.

When the whole MyChildUI composable recomposes, the value of the count will be reset to 1.

So, you should use remember to avoid issues.

Answer 2

This is because of scoped recomposition. Any Composable that is not inline and returns Unit is a scope. Compose only triggers recomposition in nearest scope. In your example it's Button's scope. You can check out this question which is very similar

Why does mutableStateOf without remember work sometimes?