👀 Views: 40 💬 Answers: 1 📅 Created: 2025-07-18

android livedata viewmodel jetpack kotlin

Hey everyone, I'm running into an issue that's driving me crazy... I'm facing an issue with `LiveData` in my Android app, specifically when trying to observe the same `LiveData` object from multiple fragments. I'm using Android Jetpack's ViewModel architecture and have implemented a shared ViewModel across these fragments. The problem arises when one fragment updates the LiveData, but the other fragment does not always reflect this change immediately. I have implemented the following: ```kotlin class SharedViewModel : ViewModel() { private val _data = MutableLiveData<String>() val data: LiveData<String> get() = _data fun updateData(newData: String) { _data.value = newData } } ``` In my fragments, I'm observing the LiveData like this: ```kotlin class FirstFragment : Fragment() { private lateinit var viewModel: SharedViewModel override fun onCreateView( inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle? ): View? { viewModel = ViewModelProvider(requireActivity()).get(SharedViewModel::class.java) viewModel.data.observe(viewLifecycleOwner, { data -> // Update UI with new data Log.d("FirstFragment", "Data updated: $data") }) return inflater.inflate(R.layout.fragment_first, container, false) } } class SecondFragment : Fragment() { private lateinit var viewModel: SharedViewModel override fun onCreateView( inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle? ): View? { viewModel = ViewModelProvider(requireActivity()).get(SharedViewModel::class.java) viewModel.data.observe(viewLifecycleOwner, { data -> // Update UI with new data Log.d("SecondFragment", "Data updated: $data") }) return inflater.inflate(R.layout.fragment_second, container, false) } } ``` When I call `viewModel.updateData("Hello World")` from `FirstFragment`, I see the log in `FirstFragment` as expected, but the log in `SecondFragment` sometimes doesn't get called until I perform a specific action (like rotating the device or navigating back and forth). I've ensured that both fragments are active in the same activity, and I'm using the latest stable version of AndroidX libraries (2.4.1). I've also checked that I'm using `viewLifecycleOwner` correctly to avoid memory leaks. Still, the behavior is inconsistent. What might be causing this issue with the LiveData updates, and how can I ensure that both fragments reflect the latest data reliably?