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I'm using Hilt, Compose, compose-navigation and I can't get a ViewModel to inject an object that I provide UNLESS I provide it via hiltViewModel. Is that purposeful? Code in thread.

Basically I originally had this

I have

```@Composable
fun HomeScreen(
    navController: NavController,
    screenTitle: String,
    viewModel: HomeScreenViewModel = viewModel()
) {
...
}```
and

```@HiltViewModel
class HomeScreenViewModel
@Inject
constructor(
    private val doSomething: Boolean,
) : ViewModel() {
...
}```
and I thought this would work.

It does *not.* 
```error: viewModel has no zero argument constructor```

BUT if I change it to this

```@Composable
fun HomeScreen(
    navController: NavController,
    screenTitle: String,
    viewModel: HomeScreenViewModel
) {
...
}```
and then in the NavHost I do this

```composable(Screen.Home.route) {
    HomeScreen(
        navController = navController,
        screenTitle = Screen.Home.title,
        viewModel = hiltViewModel()) &lt;------ Add this
}```
then everything works.

the function is viewModel? isnt it hiltViewModel or viewModels? viewModel without the last S is Koin one I think 

According to the docs here: <https://developer.android.com/jetpack/compose/libraries#viewmodel>

I should be able to do this

```class ExampleViewModel : ViewModel() { /*...*/ }

@Composable
fun MyExample(
    viewModel: ExampleViewModel = viewModel()
) {
    // use viewModel here
}```


AFAIK `viewModel`  is the default Jetpack ViewModel which simply initializes a ViewModel using default store and provider. In that case, no external dependency should be required by the ViewModel because ViewModelProvider doesn't know how to provide it. ViewModel has to have a _zero argument constructor_, meaning that no dependencies.

Now, you have a `HiltViewModel` which certainly knows how to provide those dependencies using Hilt. However, you have to use `hiltViewModel` function to initialize a Hilt specific ViewModel

Ah. So I need to use hiltViewModel(), but not necessarily in NavHost? I can just bake that into the composable itself?

Let me try.

Okay. That worked. <@U010V66NVRC> thanks for rubber ducking with me.

I think my main point of confusion was the "bad" error message. "viewModel has no zero argument constructor" led me down the wrong path.