advanced patterns with ViewModel Scope and Lifecycle Owner in a Nested Fragment Scenario
I'm stuck on something that should probably be simple... I'm deploying to production and Quick question that's been bugging me - I'm sure I'm missing something obvious here, but I'm working with an unexpected behavior when trying to observe LiveData from a ViewModel in a nested Fragment setup..... I'm using AndroidX libraries with ViewModel and LiveData for state management. The scenario arises when I have a nested Fragment that should observe changes from a ViewModel scoped to the parent Fragment. Despite using the correct LifecycleOwner, the observer seems to be receiving no updates, leading to a situation where my UI does not reflect the underlying data changes. I've tried to set up my ViewModel like this in the parent Fragment: ```kotlin class ParentFragment : Fragment() { private val viewModel: MyViewModel by viewModels() override fun onViewCreated(view: View, savedInstanceState: Bundle?) { super.onViewCreated(view, savedInstanceState) viewModel.myLiveData.observe(viewLifecycleOwner) { data -> // Handle the data update } // Adding nested fragment childFragmentManager.beginTransaction() .replace(R.id.fragment_container, NestedFragment()) .commit() } } ``` In the nested Fragment, I'm trying to observe the same LiveData like this: ```kotlin class NestedFragment : Fragment() { private val parentViewModel: MyViewModel by activityViewModels() override fun onViewCreated(view: View, savedInstanceState: Bundle?) { super.onViewCreated(view, savedInstanceState) parentViewModel.myLiveData.observe(viewLifecycleOwner) { data -> // This block is never called } } } ``` I confirmed that the LiveData is being updated in the ParentFragment, but it seems the NestedFragment is not observing the updates at all. I've ensured that I'm using the correct LifecycleOwner and that the LiveData is not empty. I also tried switching to `viewModels()` instead of `activityViewModels()`, but that leads to a different behavior where it need to find the ViewModel. Is there something I'm missing regarding scope or lifecycle in this nested Fragment setup? The expected behavior is that the NestedFragment should listen to changes made in the ParentFragment's ViewModel. Any insights would be appreciated! My development environment is Linux. What's the best practice here? How would you solve this? I recently upgraded to Kotlin 3.11. Is there a simpler solution I'm overlooking? My team is using Kotlin for this microservice. Thanks for any help you can provide!