I m getting a `ViewModel has no zero argument constructor` e

Question

I m getting a `ViewModel has no zero argument constructor` error when trying to construct a hilt view model in a compose function Anyone else experiencing this I m not using the jetpack navigation component just trying to inject a view model scoped to LocalViewModelStoreOwner current I get this error when trying to inject even a simple class with no sub dependencies My view model is provided like this `viewModel MyViewModel = viewModel ` and I m using the HiltViewModel annotation on my view model My activity and application all support hilt injection properly I m using the androidx lifecycle lifecycle viewmodel compose dependency for creating my view model Let me know if you need more information Edit this also only happens when trying to create the view model with any injected dependencies If the view model has no dependencies it works fine The `hiltViewModel ` is only supposed to be used with the navigation component which I am not using I am using an alternate navigation library this one <https github com olshevski compose navigation reimagined> but from my understanding it sets the LocalViewModelStoreOwner properly and that s what the `viewModel ` function uses I m assuming it s something to do with the view model factory

Colton Idle · Answer

Are you on 2 5 0 alpha of navigation If so go back down to 2 4 1 and you should be good

Nathaniel Rowe · Answer

I m not using the navigation component

Colton Idle · Answer

Sorry There was a recently opened bug in dagger that looked identical and it had to do with navigation On mobile but maybe you can find it

Aleksandar Aleksiev · Answer

I don t thin `viewModel` is using in this case `HiltViewModelFactory` As mentioned in the docs it will only work for Activity or Fragment annotated with ` AndroidEntryPoint` <https dagger dev api latest dagger hilt android lifecycle HiltViewModel html|https dagger dev api latest dagger hilt android lifecycle HiltViewModel html>

Nathaniel Rowe · Answer

My understanding was that the `viewModel ` method automatically used the hilt view model factory Is this not always the case My application only has a single activity and no fragments and is annotated as an android entry point

Aleksandar Aleksiev · Answer

Unfortunately no If you have a look at the `hiltViewModel ` you will see that it creates an instance of `HiltViewModelFactory` and pass it to the `viewModel ` If there s no factory provided the `viewModel ` uses the default factory of the `ViewModelStoreOwner` which in this case is `SavedStateViewModelFactory`

Nathaniel Rowe · Answer

Interesting thanks for the input The android docs claim otherwise see here <https developer android com jetpack compose libraries hilt> I guess I ll create a method to use the proper view model factory

Aleksandar Aleksiev · Answer

I had the same issue and just remembered that I only fixed it after adding dependency to `hilt navigation compose`

Aleksandar Aleksiev · Answer

And just checked yes `viewModel` creates an instance of a ` HiltViewModel` but after removing that dependency I got the same error that an instance of the model cannot be created

Nathaniel Rowe · Answer

So in my situation do you believe the fix is to supply the hilt view model factory to the view model function directly or to add the hilt navigation compose dependency I think I did add that dependency but it still didn t work

Aleksandar Aleksiev · Answer

Probably adding that dependency will jot work for you but I would try to use hilt view model factory as factory provider for the `viewModel`

Nathaniel Rowe · Answer

Okay thanks a bunch

Colton Idle · Answer

I had this issue after I iupgraded nav Downgraded nav Now I upgraded a bunch of other deps because i was getting a dupe class issue when running tests and now I get the issue stated in this thread I already have the hilt nav compose dep Anyone find a solution

Nathaniel Rowe · Answer

Are you using navigation component or a different navigation library

Nathaniel Rowe · Answer

I can speak a bit on the solution I found and why it works The specific error was because the view model was not being constructed using the hilt view model factory I was using `viewModel ` to create my view model and I wasn t in the scope of an activity or fragment for which `viewModel ` can automatically use the hilt view model factory and make everything work By scope here I basically mean what the LocalViewModelStoreOwner composition local is currently set to The navigation component sets this composition local to be the current destination s NavBackStackEntry an object which implements the ViewModelStoreOwner interface This breaks the ability of `viewModel ` to create a hilt view model As such you use the hilt nav compose dependency to get the `hiltViewModel ` function which specifically detects when your LocalViewModelStoreOwner is a NavBackStackEntry and uses the hilt view model factory in this case Because it specifically checks for NavBackStackEntry a navigation component object it didn t work for my use case which does not use navigation component My solution was to hack together a custom `hiltViewModel ` function which does work with the navigation library I m using My solution wasn t perfect as I need access to some internal types of the library I used but I opened a github discussion about adding hilt support so hopefully that will change in the future I can share the code I used too if you need which would only be the case if you are not using jetpack navigation component btw If you are using the navigation component my guess is that you either forgot to add the android entry point or hilt android app annotations to your activity application class that you aren t using `hiltViewModel ` to create your view model or the hilt nav compose version is incompatible with the navigation component version you are using Otherwise kinda sounds like a bug with the library to me but it s hard to say I do know the navigation component is a convoluted mess internally I have combed through the source code quite a bit That being said creating a custom `hiltViewModel ` method probably would work as a temporary solution if you really can t figure out what is wrong But in my experience of using the navigation component using `hiltViewModel ` when all else is set up correctly should work unless something broke in a new version recently

Colton Idle · Answer

Thanks I downgraded at 2 5 0 alpha to 2 4 0 and im back in business