Fixed
Status Update
Comments
il...@google.com <il...@google.com>
ap...@google.com <ap...@google.com> #2
Yigit, do you have time to fix it?
reemission of the same liveData is racy
reemission of the same liveData is racy
il...@google.com <il...@google.com> #4
Thanks for the detailed analysis. This may not be an issue anymore since we've started using Main.immediate there but I' not sure; I'll try to create a test case.
ap...@google.com <ap...@google.com> #5
just emitting same live data reproduces the issue.
@Test
fun raceTest() {
val subLiveData = MutableLiveData(1)
val subject = liveData(testScope.coroutineContext) {
emitSource(subLiveData)
emitSource(subLiveData) //crashes
}
subject.addObserver().apply {
testScope.advanceUntilIdle()
}
}
@Test
fun raceTest() {
val subLiveData = MutableLiveData(1)
val subject = liveData(testScope.coroutineContext) {
emitSource(subLiveData)
emitSource(subLiveData) //crashes
}
subject.addObserver().apply {
testScope.advanceUntilIdle()
}
}
ap...@google.com <ap...@google.com> #6
With 2.2.0-alpha04 (that use Main.immediate), the issue seems to be still there (I tested it by calling emitSource() twice, like your test case)
ap...@google.com <ap...@google.com> #7
yea sorry immediate does not fix it.
I actually have a WIP fix for it:
https://android-review.googlesource.com/c/platform/frameworks/support/+/1112186
if your case is the one i found (emitting same LiveData multiple times, as shown in #5) you can work around it by adding a dummy transformation.
val subLiveData = MutableLiveData(1)
val subject = liveData(testScope.coroutineContext) {
emitSource(subLiveData.map {it })
emitSource(subLiveData.map {it} )
}
I actually have a WIP fix for it:
if your case is the one i found (emitting same LiveData multiple times, as shown in #5) you can work around it by adding a dummy transformation.
val subLiveData = MutableLiveData(1)
val subject = liveData(testScope.coroutineContext) {
emitSource(subLiveData.map {it })
emitSource(subLiveData.map {it} )
}
ap...@google.com <ap...@google.com> #8
Project: platform/frameworks/support
Branch: androidx-master-dev
commit af12e75e6b4110f48e44ca121466943909de8f06
Author: Yigit Boyar <yboyar@google.com>
Date: Tue Sep 03 12:58:11 2019
Fix coroutine livedata race condition
This CL fixes a bug in liveData builder where emitting same
LiveData source twice would make it crash because the second
emission registry could possibly happen before first one is
removed as source.
We fix it by using a suspending dispose function. It does feel
a bit hacky but we cannot make DisposableHandle.dispose async
and we do not want to block there. This does not mean that there
is a problem if developer disposes it manually since our emit
functions take care of making sure it disposes (and there is
no other way to add source to the underlying MediatorLiveData)
Bug: 140249349
Test: BuildLiveDataTest#raceTest_*
Change-Id: I0b464c242a583da4669af195cf2504e2adc4de40
M lifecycle/lifecycle-livedata-ktx/api/2.2.0-alpha05.txt
M lifecycle/lifecycle-livedata-ktx/api/current.txt
M lifecycle/lifecycle-livedata-ktx/api/public_plus_experimental_2.2.0-alpha05.txt
M lifecycle/lifecycle-livedata-ktx/api/public_plus_experimental_current.txt
M lifecycle/lifecycle-livedata-ktx/api/restricted_2.2.0-alpha05.txt
M lifecycle/lifecycle-livedata-ktx/api/restricted_current.txt
M lifecycle/lifecycle-livedata-ktx/src/main/java/androidx/lifecycle/CoroutineLiveData.kt
M lifecycle/lifecycle-livedata-ktx/src/test/java/androidx/lifecycle/BuildLiveDataTest.kt
https://android-review.googlesource.com/1112186
https://goto.google.com/android-sha1/af12e75e6b4110f48e44ca121466943909de8f06
Branch: androidx-master-dev
commit af12e75e6b4110f48e44ca121466943909de8f06
Author: Yigit Boyar <yboyar@google.com>
Date: Tue Sep 03 12:58:11 2019
Fix coroutine livedata race condition
This CL fixes a bug in liveData builder where emitting same
LiveData source twice would make it crash because the second
emission registry could possibly happen before first one is
removed as source.
We fix it by using a suspending dispose function. It does feel
a bit hacky but we cannot make DisposableHandle.dispose async
and we do not want to block there. This does not mean that there
is a problem if developer disposes it manually since our emit
functions take care of making sure it disposes (and there is
no other way to add source to the underlying MediatorLiveData)
Bug: 140249349
Test: BuildLiveDataTest#raceTest_*
Change-Id: I0b464c242a583da4669af195cf2504e2adc4de40
M lifecycle/lifecycle-livedata-ktx/api/2.2.0-alpha05.txt
M lifecycle/lifecycle-livedata-ktx/api/current.txt
M lifecycle/lifecycle-livedata-ktx/api/public_plus_experimental_2.2.0-alpha05.txt
M lifecycle/lifecycle-livedata-ktx/api/public_plus_experimental_current.txt
M lifecycle/lifecycle-livedata-ktx/api/restricted_2.2.0-alpha05.txt
M lifecycle/lifecycle-livedata-ktx/api/restricted_current.txt
M lifecycle/lifecycle-livedata-ktx/src/main/java/androidx/lifecycle/CoroutineLiveData.kt
M lifecycle/lifecycle-livedata-ktx/src/test/java/androidx/lifecycle/BuildLiveDataTest.kt
il...@google.com <il...@google.com> #9
As part of this change:
- the SavedStateViewModelFactory(Fragment) and SavedStateViewModelFactory(FragmentActivity) constructors have been removed (as viewmodel-savedstate no longer depends on Fragments)
- When you use the ViewModelProvider(ViewModelStoreOwner) constructor or ViewModelProviders.of() with an Activity / Fragment / Navigation Graph ViewModelStoreOwner, you'll be using the correct SavedStateViewModelFactory - no custom factory is needed
- When you use the Kotlin property delegates such as 'by viewModels()', 'by activityViewModels()' or 'by navGraphViewModels()', you'll be using the correct SavedStateViewModelFactory - again, no custom factory needed
This will be part of:
- androidx.lifecycle viewmodel 2.2.0-alpha03
- androidx.lifecycle viewmodel-savedstate 1.0.0-alpha03
- androidx.activity 1.1.0-alpha02
- androidx.fragment 1.2.0-alpha02
- androidx.navigation 2.2.0-alpha01
- the SavedStateViewModelFactory(Fragment) and SavedStateViewModelFactory(FragmentActivity) constructors have been removed (as viewmodel-savedstate no longer depends on Fragments)
- When you use the ViewModelProvider(ViewModelStoreOwner) constructor or ViewModelProviders.of() with an Activity / Fragment / Navigation Graph ViewModelStoreOwner, you'll be using the correct SavedStateViewModelFactory - no custom factory is needed
- When you use the Kotlin property delegates such as 'by viewModels()', 'by activityViewModels()' or 'by navGraphViewModels()', you'll be using the correct SavedStateViewModelFactory - again, no custom factory needed
This will be part of:
- androidx.lifecycle viewmodel 2.2.0-alpha03
- androidx.lifecycle viewmodel-savedstate 1.0.0-alpha03
- androidx.activity 1.1.0-alpha02
- androidx.fragment 1.2.0-alpha02
- androidx.navigation 2.2.0-alpha01
da...@gmail.com <da...@gmail.com> #10
It seems like this change causes an exception such as:
Fatal Exception: java.lang.IllegalArgumentException
SavedStateProvider with the given key is already registered
Using the latest fragment/architecture component dependencies.
I am using "by activityViewModels" to get my viewModel, and "requireActivity().viewModelStore.clear()" to destroy it. Then, when getting the viewmodel is called again, it crashes because of the mentioned exception.
Fatal Exception: java.lang.IllegalArgumentException
SavedStateProvider with the given key is already registered
Using the latest fragment/architecture component dependencies.
I am using "by activityViewModels" to get my viewModel, and "requireActivity().viewModelStore.clear()" to destroy it. Then, when getting the viewmodel is called again, it crashes because of the mentioned exception.
il...@google.com <il...@google.com> #11
Re #10 - please file a new bug with a sample project that reproduces your issue.
Description
Version used: 2.2.0-alpha01
Most components, such as ComponentActivity and Fragment, seem to use AndroidViewModelFactory as the default factory. It would be great if the default could be updated to be a SavedStateVMFactory as it offers strictly more functionality.