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Unexpected NullPointerException When Accessing ViewModel in Fragment with Hilt Dependency Injection

👀 Views: 22 đŸ’Ŧ Answers: 1 📅 Created: 2025-06-14
android hilt viewmodel kotlin

I've encountered a strange issue with Can someone help me understand I'm experiencing a `NullPointerException` when trying to access my `ViewModel` within a `Fragment` that is injected via Hilt... Here's the relevant code snippet for my `Fragment`: ```kotlin @AndroidEntryPoint class MyFragment : Fragment() { private val myViewModel: MyViewModel by viewModels() override fun onViewCreated(view: View, savedInstanceState: Bundle?) { super.onViewCreated(view, savedInstanceState) myViewModel.someLiveData.observe(viewLifecycleOwner) { data -> // Update UI with data } } } ``` This `ViewModel` is defined as follows: ```kotlin @HiltViewModel class MyViewModel @Inject constructor(private val repository: MyRepository) : ViewModel() { val someLiveData: LiveData<String> = repository.getData() } ``` I have confirmed that my `MyRepository` is also set up with Hilt, as shown below: ```kotlin @Module @InstallIn(SingletonComponent::class) object RepositoryModule { @Provides fun provideRepository(): MyRepository { return MyRepository() } } ``` However, I'm getting a `NullPointerException` on the line where I observe `someLiveData`. The stack trace points to the line in the `Fragment`, indicating that `myViewModel` is null. I've ensured that `@AndroidEntryPoint` is applied to the `Fragment`. I've tried rebuilding the project and invalidating caches, but the issue persists. Is there something I might be missing in the Hilt setup, or could this be a timing issue with how dependencies are injected? Any suggestions would be greatly appreciated! Thanks, I really appreciate it! I'm working with Kotlin in a Docker container on CentOS. I'd love to hear your thoughts on this.