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.

Project: platform/frameworks/support
Branch: androidx-main

commit 57ca221882695bd6a52549f4d9ea3b812e6fe87c
Author: Simon Schiller <simonschiller@users.noreply.github.com>
Date: Mon Mar 22 16:09:30 2021

[GH] [FragmentStrictMode] Detect <fragment> tag usage

## Proposed Changes

- Detect `<fragment>` tag usage inside XML layouts

## Testing

Test: See `FragmentStrictModeTest#detectFragmentTagUsage`

## Issues Fixed

Fixes: 153738235

This is an imported pull request from

https://github.com/androidx/androidx/pull/141.

Resolves #141
Github-Pr-Head-Sha: 4ea052596e4341b9f11bcf335e2bc38045a91f19
GitOrigin-RevId: 62e7487aa4874eef6bb556490e193717cf937251
Change-Id: Iae48578e85e4e4897f806d7ade2e2a660adf9479

M fragment/fragment/api/public_plus_experimental_current.txt
M fragment/fragment/api/restricted_current.txt
M fragment/fragment/src/androidTest/java/androidx/fragment/app/strictmode/FragmentStrictModeTest.kt
M fragment/fragment/src/main/java/androidx/fragment/app/FragmentLayoutInflaterFactory.java
M fragment/fragment/src/main/java/androidx/fragment/app/strictmode/FragmentStrictMode.java
A fragment/fragment/src/main/java/androidx/fragment/app/strictmode/FragmentTagUsageViolation.java

https://android-review.googlesource.com/1649748

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

Project: platform/frameworks/support
Branch: androidx-main

commit d938453e52702fb48836cbf08b751c6354a734dc
Author: Ian Lake <ilake@google.com>
Date: Tue Mar 02 10:57:20 2021

Let FragmentViewLifecycleOwner implement ViewModelStoreOwner

SavedStateViewModelFactory makes some assumptions that
the SavedStateRegistryOwner is also a ViewModelStoreOwner.
This is almost always the case, except when using the
ViewTree APIs in Fragments. This change makes it so
that the internal FragmentViewLifecycleOwner that is
tied to the Fragment's View Lifecycle implements
ViewModelStoreOwner as well (delegating to the Fragment's
ViewModelStore).

Relnote: "Using `SavedStateViewModelFactory` now works
when used with the `SavedStateRegistryOwner` returned by
using `findViewTreeSavedStateRegistryOwner()` from a
Fragment's View."
Test: updated tests pass
BUG: 181577191

Change-Id: I21acf18f70ab6dcc60f5946d5b0d878e12bc76df

M fragment/fragment/src/androidTest/java/androidx/fragment/app/FragmentViewLifecycleTest.kt
M fragment/fragment/src/main/java/androidx/fragment/app/Fragment.java
M fragment/fragment/src/main/java/androidx/fragment/app/FragmentViewLifecycleOwner.java

https://android-review.googlesource.com/1612805

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