: Can't access the Fragment View's LifecycleOwner when getView() is null i.e., before onCreateView() or after onDestroyView()

Question

I am using live data in my application for all the network calls and response handling.

In one of the scenarios, my recycler view is loading some data in its view holder's onBind and the response is updating the UI. In order to do so, I have to provide a lifecycleOwner to the observer.

As recycler view doesn't have any lifecycle owner of its own, I am using the parent fragment for that by using parentFragment.viewlifecycleOwner but somehow it is giving an error.

How can a view Holder have its instance when the parent fragment is not having its instance?

viewModel.responseState.observe(parentFragment.viewLifecycleOwner, Observer {
    updateUI(it)
})

Fatal Exception: java.lang.IllegalStateException: Can't access the Fragment View's LifecycleOwner when getView() is null i.e., before onCreateView() or after onDestroyView()

The problem was that my ViewHolder was fetching some data from the server and after the response was received the actual data for the holder was created, which again had some observers which were attached using the parent fragment's lifecycle owner. But if I navigated away from the fragment while my viewholder was fetching the data, the parent fragment view was destroyed, and when the viewholder got the response and tried attaching the observer with the parent fragment's lifecycle owner, it throws the above-mentioned error as there was no view left with the parent fragment. — Utkarsh Singh, Nov 21 '19 at 11:05

score 15 · Answer 1 · edited May 06 '22 at 12:15

This can be fixed, by triggering the logic which is raising the error, from around end of onCreateView(...) callback (not onCreate(...) nor onAttach(...)).

In getViewLifecycleOwner() documentation, I don't think, I can explain better:

The first method where it is safe to access the view lifecycle is onCreateView(LayoutInflater, ViewGroup, Bundle) under the condition that you must return a non-null view (an IllegalStateException will be thrown if you access the view lifecycle but don't return a non-null view).

The view lifecycle remains valid through the call to onDestroyView(), after which getView() will return null, the view lifecycle will be destroyed, and this method will throw an IllegalStateException. Consider using getViewLifecycleOwnerLiveData() or FragmentTransaction.runOnCommit(Runnable) to receive a callback for when the Fragment's view lifecycle is available.

public LifecycleOwner getViewLifecycleOwner() {
    if (mViewLifecycleOwner == null) {
        throw new IllegalStateException("Can't access the Fragment View's LifecycleOwner when "
                + "getView() is null i.e., before onCreateView() or after onDestroyView()");
    }
    return mViewLifecycleOwner;
}

score 9 · Answer 2 · answered Mar 10 '21 at 15:31

9

i faced the same problem and i could fix it with the code bellow , just check if the view is null or not

     if ( view != null)
       viewModel.responseState.observe(parentFragment.viewLifecycleOwner, Observer {
       updateUI(it) })

answered Mar 10 '21 at 15:31

Abdev

301
2
7

score 4 · Answer 3 · answered Jun 08 '21 at 08:53

4

The solution for me was writing code inside onViewCreated insted of writing in onCreateView.... and my problem fixed.

answered Jun 08 '21 at 08:53

Alireza Haji gholamreza

158
5

3

I am using it in my onViewCreated method and still give error in some devices. – Rohit Jakhar Mar 15 '22 at 04:35
This worked for me when I was trying to add a callback on a onBackPressedDispatcher – Leonardo Sibela Mar 13 '23 at 15:33

acarrell · Answer 4 · 2021-11-15T17:48:24.960

1

The problem is that the observer is still active on the parent's viewLifecycleOwner even after the view is destroyed (when you navigate to the next fragment). The most reliable way to fix this is to clear out the observers.

override fun onDestroyView()
    viewModel.responseState.removeObservers(parentFragment.viewLifecycleOwner)
    super.onDestroyView()
}

edited Nov 15 '21 at 17:48

answered Nov 11 '21 at 15:59

acarrell

11
2

Please provide some explanation for your solution. – kiner_shah Nov 14 '21 at 11:30
it cause crash in my app :( – Vanya Rachel Jun 14 '22 at 04:19

score 0 · Answer 5 · answered Dec 24 '19 at 18:31

The solution for me was simplified. I am using separate observers - one for the network which is using Lifecycleowner from the main activity (or just from any activity) and one for the fragment view (model view view model).

score 0 · Answer 6 · answered Sep 11 '21 at 03:53

 myModel.getOfflineData().observeForever(new Observer<List<indiaStateModel>>() {
                @Override
                public void onChanged(List<indiaStateModel> indiaStateModels) {
                    adapter = new stateAdapter(indiaStateModels);
                    recyclerView.setAdapter(adapter);
                }
            });

// use this forever observer when your are getting that error // mainly this error comes when you try to change your phone theme to dark to light or light to dark

score 0 · Answer 7 · answered Sep 14 '21 at 03:50

0

Best To Use FLow() instead of LiveData()

Convert LiveData() to Flow()

Before

viewModel.responseState.observe(parentFragment.viewLifecycleOwner, Observer {
    updateUI(it)
})

AFTER

lifecycleScope.launch {

viewModel.responseState.asFlow().collectLatest{
 
updateUI(it)

l̥

}

}

answered Sep 14 '21 at 03:50

Anuj Kumar Rai

51
1
4

If you have a new question, please ask it by clicking the [Ask Question](https://stackoverflow.com/questions/ask) button. Include a link to this question if it helps provide context. - [From Review](/review/late-answers/29817703) – Rishabh Deep Singh Sep 14 '21 at 08:34

score 0 · Answer 8 · answered Nov 11 '21 at 14:30

0

In my case I was setting observer inside view runnable:

view.post(() ->{
    ...
    viewModel.getDate().observe();
})

answered Nov 11 '21 at 14:30

Te Global

3
3

score 0 · Answer 9 · answered Sep 12 '22 at 15:52

I used as suggested by android studio viewLifecycleOwnerLiveData. so for your case will be something like

    parentFragment.viewLifecycleOwnerLiveData.value?.let { nonNullViewLifecycleOwner -> 
       viewModel.responseState.observe(nonNullViewLifecycleOwner, Observer   {
          updateUI(it)
       })
    }

Hope it helps!

Viroth · Answer 10 · 2022-12-01T04:37:24.057

0

observe view model live data in onViewCreated function. Or you can do this check this out

edited Dec 01 '22 at 04:37

answered Dec 01 '22 at 03:15

Viroth

429
5
14

score 0 · Answer 11 · answered Mar 22 '23 at 22:53

0

I resolved this by making sure I was clearing all my subscriptions inside the onDestroyView() of my Fragment than in the onDestroy(). This totally fixed it ! My code was trying to access the view after the onDestroyView() was called.

answered Mar 22 '23 at 22:53

Roehit Kadam

101
1
11

score -2 · Answer 12 · answered Dec 14 '19 at 20:12

-2

The solution, as your comment, is to ensure the fragment's view is not null. This happened to me with a Fragment inside a ViewPager.

answered Dec 14 '19 at 20:12

Emmanuel Guerra

1,372
1
12
20

aneez ayyappan · Answer 13 · 2023-04-20T07:11:04.817

-3

override fun onDestroyView()
    viewModel.responseState.removeObservers(parentFragment.viewLifecycleOwner)
    super.onDestroyView()
}

Check if there view is Destroy then Lifecycle Owner cant perform of updating UI so it is getting crash

so stop the action if on View has Destroy

edited Apr 20 '23 at 07:11

answered Mar 30 '23 at 05:45

aneez ayyappan

1
2

1

Please don't post only code as answer, but also provide an explanation what your code does and how it solves the problem of the question. Answers with an explanation are usually more helpful and of better quality, and are more likely to attract upvotes. – Mark Rotteveel Apr 01 '23 at 09:02

: Can't access the Fragment View's LifecycleOwner when getView() is null i.e., before onCreateView() or after onDestroyView()

13 Answers13