App Crash once replace Fragment for scoped ViewModel

Question

Bug

I was found an issue when I try to open fragment and then replace with the same fragment. In our prod application, it's a popular case.

java.lang.IllegalStateException: Definition without any InstanceContext - [type:Scope,scope:'com.abc.view.fragment.BrowseTaskFragment', primary_type:'com.abc.viewModel.BrowseTaskVM']
        at org.koin.core.definition.BeanDefinition.resolveInstance(BeanDefinition.kt:72)
        at org.koin.core.scope.Scope.resolveInstance(Scope.kt:141)
        at org.koin.core.scope.Scope.get(Scope.kt:131)
        at com.abc.view.fragment.BrowseTaskFragment$$special$$inlined$inject$1.invoke(Scope.kt:274)
        at kotlin.SynchronizedLazyImpl.getValue(LazyJVM.kt:74)
        at com.abc.view.fragment.BrowseTaskFragment.getMViewModel(Unknown Source:25)
        at com.abc.view.fragment.BrowseTaskFragment.getMViewModel(BrowseTaskFragment.kt:37)
        at com.abc.base.BaseFragment.performViewModelBinding(BaseFragment.kt:55)
        at com.abc.base.BaseFragment.onViewCreated(BaseFragment.kt:31)
        at androidx.fragment.app.FragmentManagerImpl.moveToState(FragmentManager.java:1471)
        at androidx.fragment.app.FragmentManagerImpl.moveFragmentToExpectedState(FragmentManager.java:1784)
        at androidx.fragment.app.FragmentManagerImpl.moveToState(FragmentManager.java:1852)
        at androidx.fragment.app.BackStackRecord.executeOps(BackStackRecord.java:802)
        at androidx.fragment.app.FragmentManagerImpl.executeOps(FragmentManager.java:2625)
        at androidx.fragment.app.FragmentManagerImpl.executeOpsTogether(FragmentManager.java:2411)
        at androidx.fragment.app.FragmentManagerImpl.removeRedundantOperationsAndExecute(FragmentManager.java:2366)
        at androidx.fragment.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:2273)
        at androidx.fragment.app.FragmentManagerImpl$1.run(FragmentManager.java:733)
        at android.os.Handler.handleCallback(Handler.java:873)
        at android.os.Handler.dispatchMessage(Handler.java:99)
        at android.os.Looper.loop(Looper.java:201)
        at android.app.ActivityThread.main(ActivityThread.java:6810)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:873)

Steps to reproduce the behavior:

• I have BottomNavigationView once I tap on existing fragment which is visible, getting above crash.

Koin version: 2.0.1

Module

val viewModelModule = module {
     scope(named<BrowseTaskFragment>()) {
        scoped { BrowseTaskVM() }
      }
    }

Application class

startKoin {
            androidContext(this@AbcApplication)
            modules(listOf(appModule, stateModule, apiModule, viewModelModule))
        }

Answer 1

You can do this by create scope. First in your module class create scope by named koin method

val viewModelModule = module {
 scope(named<BrowseTaskFragment>()) {
   scoped { BrowseTaskVM() }
  }
}

Second in your fragment

private val viewModelScope = getKoin().getOrCreateScope("Scope1",named<BrowseTaskFragment>())
private val browseTaskVM: BrowseTaskVM= viewModelScope.get()

Last in an onDestoy method close your scope.

 override fun onDestroy() {
    super.onDestroy()
    viewModelScope.close()
}