ViewModel

class MainViewModel(private val dataStore: DataStore<Preferences>) : ViewModel() {

    private val _name = MutableLiveData<String>()
    val name: LiveData<String>
        get() = _name

    fun fetch() {
            viewModelScope.launch {
                dataStore.data
                    .catch { _name.postValue(it.message) }
                    .map {
                        _name.postValue(it[NAME_KEY])
                        ...
                    }
                    .first()
            }
            
    fun saveName(name: String) {
        viewModelScope.launch {
            dataStore.edit { it[NAME_KEY] = name }
            _name.postValue(name)
        }
    }

}