Android Jetpack Compose TextField 在输入新字符时不更新

我从开发人员站点跟踪了this document个. 我希望显示来自用户输入的OutlinedTextField中的文本，并使其在配置更改后仍然有效.

使用下面的代码，当用户从键盘输入文本时，OutlinedTextField不会更新文本.

HelloContent(name = city.name, onNameChange = { city.name = it})//Doesn't work

但是，下面这行代码可以正常工作:

HelloContent(name = temp, onNameChange = { temp = it})//Work

下面是我用来实现的代码:

@Composable
fun HelloScreen() {
    var city by rememberSaveable(stateSaver = CitySaver) {
        mutableStateOf(City("Hanoi","VietNam"))
    }
    var temp by rememberSaveable {
        mutableStateOf("")
    }
    Column {
        HelloContent(name = city.name, onNameChange = { city.name = it})//Doesn't work
        HelloContent(name = temp, onNameChange = { temp = it})//Work
    }
}
@Composable
    fun HelloContent(name: String, onNameChange: (String) -> Unit) {
        Column(modifier = Modifier.padding(16.dp)) {
            Text(
                text = "Hello, $name",
                modifier = Modifier.padding(bottom = 8.dp),
                style = MaterialTheme.typography.h5
            )
            OutlinedTextField(
                value = name,
                onValueChange = onNameChange,
                label = { Text("Name") }
            )
        }
    }
data class City(var name: String, val country: String)
val CitySaver = run {
    val nameKey = "Name"
    val countryKey = "Country"
    mapSaver(save = {mapOf(nameKey to it.name,countryKey to it.country)},
        restore = {City(it[nameKey] as String,it[countryKey] as String)})
}

你能帮我把第一个代码块修复好吗？

HelloContent(name = city.name, onNameChange = { city.name = it})//Doesn't work