Exception when creating a ViewModel for a View in a Fragment - IllegalStateException: Internal error: OnRecreation should be registered only on componentsthat implement ViewModelStoreOwner [181577191]

Fixed

Bug

Status Update

No update yet.

Description

tf...@gmail.com

created issue #1

Mar 2, 2021 12:15PM

Component used: lifecycle-viewmodel-ktx

Version used: 2.3.0

Devices/Android versions reproduced on: Pixel 4 running Android 10

Sample project to trigger the issue: https://github.com/tfcporciuncula/view-tree-owner-bug

You can repro the issue by cloning that repo, running it, and then rotating the screen causing a config change.

This is the code I'm using to create a ViewModel in a View (as you can see here):

private val viewModel by lazy {
  val factory = object : AbstractSavedStateViewModelFactory(findViewTreeSavedStateRegistryOwner()!!, null) {
    override fun <T : ViewModel?> create(key: String, modelClass: Class<T>, handle: SavedStateHandle): T {
      return MyViewModel() as T
    }
  }
  ViewModelProvider(findViewTreeViewModelStoreOwner()!!, factory).get(MyViewModel::class.java)
}

Everything works fine, but the app crashes on orientation change with the following stacktrace:

Process: com.tfcporciuncula.viewtreeownerbug, PID: 3467
    java.lang.IllegalStateException: Internal error: OnRecreation should be registered only on componentsthat implement ViewModelStoreOwner
        at androidx.lifecycle.SavedStateHandleController$OnRecreation.onRecreated(SavedStateHandleController.java:80)
        at androidx.savedstate.Recreator.reflectiveNew(Recreator.java:92)
        at androidx.savedstate.Recreator.onStateChanged(Recreator.java:64)
        at androidx.lifecycle.LifecycleRegistry$ObserverWithState.dispatchEvent(LifecycleRegistry.java:354)
        at androidx.lifecycle.LifecycleRegistry.forwardPass(LifecycleRegistry.java:265)
        at androidx.lifecycle.LifecycleRegistry.sync(LifecycleRegistry.java:307)
        at androidx.lifecycle.LifecycleRegistry.moveToState(LifecycleRegistry.java:148)
        at androidx.lifecycle.LifecycleRegistry.handleLifecycleEvent(LifecycleRegistry.java:134)
        at androidx.fragment.app.FragmentViewLifecycleOwner.handleLifecycleEvent(FragmentViewLifecycleOwner.java:62)
        at androidx.fragment.app.Fragment.restoreViewState(Fragment.java:650)
        at androidx.fragment.app.Fragment.restoreViewState(Fragment.java:2997)
        at androidx.fragment.app.Fragment.performActivityCreated(Fragment.java:2988)
        at androidx.fragment.app.FragmentStateManager.activityCreated(FragmentStateManager.java:577)
        at androidx.fragment.app.FragmentStateManager.moveToExpectedState(FragmentStateManager.java:285)
        at androidx.fragment.app.FragmentStore.moveToExpectedState(FragmentStore.java:112)
        at androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1636)
        at androidx.fragment.app.FragmentManager.dispatchStateChange(FragmentManager.java:3112)
        at androidx.fragment.app.FragmentManager.dispatchActivityCreated(FragmentManager.java:3056)
        at androidx.fragment.app.FragmentController.dispatchActivityCreated(FragmentController.java:251)
        at androidx.fragment.app.FragmentActivity.onStart(FragmentActivity.java:473)
        at androidx.appcompat.app.AppCompatActivity.onStart(AppCompatActivity.java:210)
        at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1425)
        at android.app.Activity.performStart(Activity.java:7825)
        at android.app.ActivityThread.handleStartActivity(ActivityThread.java:3294)
        at android.app.servertransaction.TransactionExecutor.performLifecycleSequence(TransactionExecutor.java:221)
        at android.app.servertransaction.TransactionExecutor.cycleToPath(TransactionExecutor.java:201)
        at android.app.servertransaction.TransactionExecutor.executeLifecycleState(TransactionExecutor.java:173)
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:97)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2016)
        at android.os.Handler.dispatchMessage(Handler.java:107)
        at android.os.Looper.loop(Looper.java:214)
        at android.app.ActivityThread.main(ActivityThread.java:7356)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930)

The crash has a pretty clear cause which is this:

if (!(owner instanceof ViewModelStoreOwner)) {
    throw new IllegalStateException(
            "Internal error: OnRecreation should be registered only on components"
                    + "that implement ViewModelStoreOwner");
}

So it seems there's this implicit requirement of having the SavedStateRegistryOwner also be a ViewModelStoreOwner, and that's not the case for the view when it's in a fragment: its SavedStateRegistryOwner is a FragmentViewLifecycleOwner, which is only a SavedStateRegistryOwner and not a ViewModelStoreOwner.

It feels like findViewTreeSavedStateRegistryOwner() should return the fragment itself (like findViewTreeSavedStateRegistryOwner()) instead of the FragmentViewLifecycleOwner, so this would work. Or am I doing something wrong here?

If the view is in an activity everything works fine -- findViewTreeSavedStateRegistryOwner() returns the activity in this case, which is also a ViewModelStoreOwner so everything is good.

Comments

il...@google.com <il...@google.com> #2Mar 2, 2021 05:18PM

Reassigned to il...@google.com.

Hi Ed, Thank you so much for these suggestions. I've been reviewing them and merging them in. Hopefully it should be live. I've included a thank you note too in the article.

ap...@google.com <ap...@google.com> #3Mar 2, 2021 08:30PM

Great! Thanks a lot, I'll look for the live updates soon!

il...@google.com <il...@google.com> #4Mar 2, 2021 08:38PM

Marked as fixed.

This has been fixed internally and we're looking to include it in the Fragment 1.3.1 release.

tf...@gmail.com <tf...@gmail.com> #5Mar 24, 2021 09:54PM

Are there any plans to include this in any of the next releases? I just checked 1.3.2 and it doesn't seem to be there.

il...@google.com <il...@google.com> #6Mar 24, 2021 10:53PM

Sorry, looks like this slipped through the cracks. I'll actually add this to the next release's hotlist.

b9...@gmail.com <b9...@gmail.com> #7Apr 22, 2021 03:27PM

I upgrade 1.3.3 from 1.3.2 and can't create ViewModel in compose via androidx.lifecycle.viewmodel.compose.viewModel<T>() anymore.

il...@google.com <il...@google.com> #8Apr 22, 2021 03:28PM

Re #7 - please file a new bug with a sample project that reproduces your issue.

b9...@gmail.com <b9...@gmail.com> #9Apr 22, 2021 05:28PM

Re #8 I could point out the code directly. I don't know how to describe the issue.

    public ViewModelProvider(@NonNull ViewModelStoreOwner owner) {
        this(owner.getViewModelStore(), owner instanceof HasDefaultViewModelProviderFactory
                ? ((HasDefaultViewModelProviderFactory) owner).getDefaultViewModelProviderFactory()
                : NewInstanceFactory.getInstance());
    }

ViewModel compose extension use this constructor by default. Because FragmentViewLifecycleOwner didn't implement HasDefaultViewModelProviderFactory, so that NewInstanceFactory will be used to create ViewModel. Which means DI framework like Hilt will failed.

il...@google.com <il...@google.com> #10Apr 22, 2021 05:31PM

Re #9 - please file a new bug so we can track that work.

b9...@gmail.com <b9...@gmail.com> #11Apr 22, 2021 06:02PM

Re #10, here it is