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Strange behavior with ViewModel and LiveData when navigating between fragments in Android 14

๐Ÿ‘€ Views: 47 ๐Ÿ’ฌ Answers: 1 ๐Ÿ“… Created: 2025-06-06
android viewmodel livedata navigation-component kotlin

I've looked through the documentation and I'm still confused about I'm experiencing an scenario where my `ViewModel` seems to lose its state when navigating back to a fragment that uses `LiveData`... I'm using Android 14 and the Navigation Component to manage my fragments. The `ViewModel` is scoped to the activity, and the `LiveData` updates correctly when I'm in the fragment, but once I navigate away and return, it appears to reset and doesn't reflect the latest data. Here's a simple example of my code: ```kotlin class MyFragment : Fragment() { private lateinit var viewModel: MyViewModel override fun onCreateView( inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle? ): View? { viewModel = ViewModelProvider(requireActivity()).get(MyViewModel::class.java) viewModel.data.observe(viewLifecycleOwner, Observer { data -> // Update UI with data }) return inflater.inflate(R.layout.fragment_my, container, false) } } ``` And hereโ€™s the `ViewModel`: ```kotlin class MyViewModel : ViewModel() { private val _data = MutableLiveData<String>() val data: LiveData<String> get() = _data fun updateData(newData: String) { _data.value = newData } } ``` Whatโ€™s strange is that when I navigate away and back, the `LiveData` seems to revert to its initial state. Iโ€™ve tried using `setHasStableIds(true)` on my adapter and ensuring that the `ViewModel` is properly scoped, but nothing seems to work. I also verified that the data in the `ViewModel` is indeed being updated before navigating away. Iโ€™m not seeing any specific behavior messages in the logcat, just the behavior itself. Has anyone encountered a similar scenario or have any suggestions on how I might resolve this? For context: I'm using Kotlin on Linux. Is there a better approach?