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Hey I am working in Android Kotlin. I am learning this <https://developer.android.com/kotlin/flow/stateflow-and-sharedflow#stateflow|LatestNewsUiState> sealed class example from Android doc. I made my own `sealed class` example. But I am confused little bit, how can I achieved this. Is I am doing right for my scenario or not?

*DataState.kt*
```sealed class DataState {
    data class DataFetch(val data: List&lt;Xyz&gt;?) : DataState()
    object EmptyOnFetch : DataState()
    object ErrorOnFetch : DataState()
}```
*viewmodel.kt*
```var dataMutableStateFlow = MutableStateFlow&lt;DataState&gt;(DataState.EmptyOnFetch)

fun fetchData() {
        viewModelScope.launch {
            val result = repository.getData()
            result.handleResult(
                onSuccess = { response -&gt;
                    if (response?.items.isNullOrEmpty()) {
                        dataMutableStateFlow.value = DataState.EmptyOnFetch
                    } else {
                        dataMutableStateFlow.value = DataState.DataFetch(response?.items)
                    }
                },
                onError = {
                    dataMutableStateFlow.value = DataState.ErrorOnFetch
                }
            )
        }
}

fun fetchMoreData() {
        viewModelScope.launch {
            val result = repository.getData()
            result.handleResult(
                onSuccess = { response -&gt;
                    if (response?.items.isNullOrEmpty()) {
                        dataMutableStateFlow.value = DataState.EmptyOnFetch
                    } else {
                        dataMutableStateFlow.value = DataState.DataFetch(response?.items)
                    }
                },
                onError = {
                    dataMutableStateFlow.value = DataState.ErrorOnFetch
                }
            )
        }
}```
*Activity.kt*
```lifecycleScope.launchWhenStarted {
            viewModel.dataMutableStateFlow.collectLatest { state -&gt;
                when (state) {
                    is DataState.DataFetch -&gt; {
                       binding.group.visibility = View.VISIBLE
                    }
                    DataState.EmptyOnFetch,
                    DataState.ErrorOnFetch -&gt; {
                        binding.group.visibility = View.GONE
                    }
                }
            }
        }
}```

I have some points which I want to achieve in the standard ways.
*1.* When your first initial api call `fetchData()` if data is not *null* or *empty* then we need to *show* view. If data is *empty* or *null* then we need to *hide* the view. But if api *fail* then we need to show an *error message*.
*2.* When view is *visible* and view is showing some data. Then we call another api `fetchMoreData()` and data is *empty* or *null* then I don't want to hide view as per code is written above. And If api *fails* then we show *error message*.
Thanks in advance