[SOLVED?] `sample-mvi` crashes on Start about mosby

[drbear95]

What is the status of this case?

[ValeriusGC]

Here is the change i made to fix this problem:
MviBasePresenter.java

        Subject<I> intentRelay = ReplaySubject.create();
        //Subject<I> intentRelay = UnicastSubject.create();

this was inserted on 513d1e9 ("use unicast subject", 2018-04-08)

[sockeqwe]

Sorry for the long delay. I'm quite busy at the moment, I will take a look at this at the end of July.
As far as I can tell is that all automated tests (testing Mosby internals) are passing. Hence (without having investigated into this bug) I have the feeling that this is a Sample App issue.

[p8499]

When I upgrade mosby library from 3.1.0 to 3.1.1 I faced with this problem too.

[p8499]

Maybe UnicastSubject conflicts with the navigation feature,
stateObservable.share().map{...}.addTo(compositeDisposable)
thus makes it subscribed by two observables.

[drbear95]

Im facing this problem in my app, i tried with ReplaySubject but it doesn't work.

[sockeqwe]

What exactly is the issue that you face in your app? Simon <[email protected]> schrieb am Do., 30. Mai 2019, 12:34:

…

Im facing this problem in my app, i tried with ReplaySubject but it doesn't work. — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#314?email_source=notifications&email_token=AAEOPLSY7KK4YJEL66G4CWTPX6UUPA5CNFSM4FB6S7PKYY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGODWR7VPY#issuecomment-497285823>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAEOPLUG3OADVNMS3BVWNGLPX6UUPANCNFSM4FB6S7PA> .

[drbear95]

Here is my stack trace

 java.lang.IllegalStateException: ViewState observable must not reach error state - onError()
        at com.hannesdorfmann.mosby3.mvi.DisposableViewStateObserver.onError(DisposableViewStateObserver.java:22)
        at io.reactivex.internal.operators.observable.ObservableObserveOn$ObserveOnObserver.checkTerminated(ObservableObserveOn.java:281)
        at io.reactivex.internal.operators.observable.ObservableObserveOn$ObserveOnObserver.drainNormal(ObservableObserveOn.java:172)
        at io.reactivex.internal.operators.observable.ObservableObserveOn$ObserveOnObserver.run(ObservableObserveOn.java:255)
        at io.reactivex.android.schedulers.HandlerScheduler$ScheduledRunnable.run(HandlerScheduler.java:119)
        at android.os.Handler.handleCallback(Handler.java:739)
        at android.os.Handler.dispatchMessage(Handler.java:95)
        at android.os.Looper.loop(Looper.java:135)
        at android.app.ActivityThread.main(ActivityThread.java:5221)
        at java.lang.reflect.Method.invoke(Native Method)
        at java.lang.reflect.Method.invoke(Method.java:372)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
     Caused by: java.lang.IllegalStateException: Only a single observer allowed.
        at io.reactivex.subjects.UnicastSubject.subscribeActual(UnicastSubject.java:311)
        at io.reactivex.Observable.subscribe(Observable.java:12090)
        at io.reactivex.internal.operators.observable.ObservableDoOnEach.subscribeActual(ObservableDoOnEach.java:42)
        at io.reactivex.Observable.subscribe(Observable.java:12090)
        at io.reactivex.internal.operators.observable.ObservableSwitchMap.subscribeActual(ObservableSwitchMap.java:51)
        at io.reactivex.Observable.subscribe(Observable.java:12090)
        at io.reactivex.internal.operators.observable.ObservableMap.subscribeActual(ObservableMap.java:32)
        at io.reactivex.Observable.subscribe(Observable.java:12090)
        at io.reactivex.internal.operators.observable.ObservableFlatMap$MergeObserver.subscribeInner(ObservableFlatMap.java:165)
        at io.reactivex.internal.operators.observable.ObservableFlatMap$MergeObserver.onNext(ObservableFlatMap.java:139)
        at io.reactivex.internal.operators.observable.ObservableFromArray$FromArrayDisposable.run(ObservableFromArray.java:108)
        at io.reactivex.internal.operators.observable.ObservableFromArray.subscribeActual(ObservableFromArray.java:37)
        at io.reactivex.Observable.subscribe(Observable.java:12090)
        at io.reactivex.internal.operators.observable.ObservableFlatMap.subscribeActual(ObservableFlatMap.java:55)
        at io.reactivex.Observable.subscribe(Observable.java:12090)
        at io.reactivex.internal.operators.observable.ObservableFlatMap$MergeObserver.subscribeInner(ObservableFlatMap.java:165)
        at io.reactivex.internal.operators.observable.ObservableFlatMap$MergeObserver.onNext(ObservableFlatMap.java:139)
        at io.reactivex.internal.operators.observable.ObservableFromArray$FromArrayDisposable.run(ObservableFromArray.java:108)
        at io.reactivex.internal.operators.observable.ObservableFromArray.subscribeActual(ObservableFromArray.java:37)
        at io.reactivex.Observable.subscribe(Observable.java:12090)
        at io.reactivex.internal.operators.observable.ObservableFlatMap.subscribeActual(ObservableFlatMap.java:55)
        at io.reactivex.Observable.subscribe(Observable.java:12090)
        at io.reactivex.internal.operators.observable.ObservableDoOnEach.subscribeActual(ObservableDoOnEach.java:42)
        at io.reactivex.Observable.subscribe(Observable.java:12090)
        at io.reactivex.internal.operators.observable.ObservableScanSeed.subscribeActual(ObservableScanSeed.java:47)
        at io.reactivex.Observable.subscribe(Observable.java:12090)
        at io.reactivex.internal.operators.observable.ObservableDoOnEach.subscribeActual(ObservableDoOnEach.java:42)
        at io.reactivex.Observable.subscribe(Observable.java:12090)
        at io.reactivex.internal.operators.observable.ObservableDistinctUntilChanged.subscribeActual(ObservableDistinctUntilChanged.java:35)
        at io.reactivex.Observable.subscribe(Observable.java:12090)

And here is my base presenter class

abstract class BasePresenter<TView : BaseView<TViewState>, TViewState: ViewState>(viewState: TViewState)
    : MviBasePresenter<TView, TViewState>(viewState) {

    protected val initialState: TViewState = viewState
    private var viewStateSnapshot: TViewState = viewState

    protected val lastViewState: TViewState
        get() = viewStateSnapshot

    override fun attachView(view: TView) {
        super.attachView(view)

        view.render(viewStateSnapshot)
    }


    override fun subscribeViewState(viewStateObservable: Observable<TViewState>, consumer: ViewStateConsumer<TView, TViewState>) {
        val viewStateStream = if(BuildConfig.DEBUG){
            viewStateObservable
        } else {
            viewStateObservable.map { it as ViewState }
                    .onErrorReturn {
                        FailureViewState()
                    }.filter { it !is FailureViewState }
                    .map { it as TViewState }
        }

        super.subscribeViewState(viewStateStream) { view, viewState ->
            this.viewStateSnapshot = viewState
            consumer.accept(view, viewState)
        }
    }

    private class FailureViewState: ViewState()
}

After changing Unicast to Relay (as ValeriusGC suggest) state is not beeing updated anymore.

[sockeqwe]

Oh ... i see, thanks for reporting! I have to think about it. It seems I have to write something custom to handle this cases ... Simon <[email protected]> schrieb am Sa., 1. Juni 2019, 16:28:

…

Here is my stack trace java.lang.IllegalStateException: ViewState observable must not reach error state - onError() at com.hannesdorfmann.mosby3.mvi.DisposableViewStateObserver.onError(DisposableViewStateObserver.java:22) at io.reactivex.internal.operators.observable.ObservableObserveOn$ObserveOnObserver.checkTerminated(ObservableObserveOn.java:281) at io.reactivex.internal.operators.observable.ObservableObserveOn$ObserveOnObserver.drainNormal(ObservableObserveOn.java:172) at io.reactivex.internal.operators.observable.ObservableObserveOn$ObserveOnObserver.run(ObservableObserveOn.java:255) at io.reactivex.android.schedulers.HandlerScheduler$ScheduledRunnable.run(HandlerScheduler.java:119) at android.os.Handler.handleCallback(Handler.java:739) at android.os.Handler.dispatchMessage(Handler.java:95) at android.os.Looper.loop(Looper.java:135) at android.app.ActivityThread.main(ActivityThread.java:5221) at java.lang.reflect.Method.invoke(Native Method) at java.lang.reflect.Method.invoke(Method.java:372) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694) Caused by: java.lang.IllegalStateException: Only a single observer allowed. at io.reactivex.subjects.UnicastSubject.subscribeActual(UnicastSubject.java:311) at io.reactivex.Observable.subscribe(Observable.java:12090) at io.reactivex.internal.operators.observable.ObservableDoOnEach.subscribeActual(ObservableDoOnEach.java:42) at io.reactivex.Observable.subscribe(Observable.java:12090) at io.reactivex.internal.operators.observable.ObservableSwitchMap.subscribeActual(ObservableSwitchMap.java:51) at io.reactivex.Observable.subscribe(Observable.java:12090) at io.reactivex.internal.operators.observable.ObservableMap.subscribeActual(ObservableMap.java:32) at io.reactivex.Observable.subscribe(Observable.java:12090) at io.reactivex.internal.operators.observable.ObservableFlatMap$MergeObserver.subscribeInner(ObservableFlatMap.java:165) at io.reactivex.internal.operators.observable.ObservableFlatMap$MergeObserver.onNext(ObservableFlatMap.java:139) at io.reactivex.internal.operators.observable.ObservableFromArray$FromArrayDisposable.run(ObservableFromArray.java:108) at io.reactivex.internal.operators.observable.ObservableFromArray.subscribeActual(ObservableFromArray.java:37) at io.reactivex.Observable.subscribe(Observable.java:12090) at io.reactivex.internal.operators.observable.ObservableFlatMap.subscribeActual(ObservableFlatMap.java:55) at io.reactivex.Observable.subscribe(Observable.java:12090) at io.reactivex.internal.operators.observable.ObservableFlatMap$MergeObserver.subscribeInner(ObservableFlatMap.java:165) at io.reactivex.internal.operators.observable.ObservableFlatMap$MergeObserver.onNext(ObservableFlatMap.java:139) at io.reactivex.internal.operators.observable.ObservableFromArray$FromArrayDisposable.run(ObservableFromArray.java:108) at io.reactivex.internal.operators.observable.ObservableFromArray.subscribeActual(ObservableFromArray.java:37) at io.reactivex.Observable.subscribe(Observable.java:12090) at io.reactivex.internal.operators.observable.ObservableFlatMap.subscribeActual(ObservableFlatMap.java:55) at io.reactivex.Observable.subscribe(Observable.java:12090) at io.reactivex.internal.operators.observable.ObservableDoOnEach.subscribeActual(ObservableDoOnEach.java:42) at io.reactivex.Observable.subscribe(Observable.java:12090) at io.reactivex.internal.operators.observable.ObservableScanSeed.subscribeActual(ObservableScanSeed.java:47) at io.reactivex.Observable.subscribe(Observable.java:12090) at io.reactivex.internal.operators.observable.ObservableDoOnEach.subscribeActual(ObservableDoOnEach.java:42) at io.reactivex.Observable.subscribe(Observable.java:12090) at io.reactivex.internal.operators.observable.ObservableDistinctUntilChanged.subscribeActual(ObservableDistinctUntilChanged.java:35) at io.reactivex.Observable.subscribe(Observable.java:12090) And here is my base presenter class abstract class BasePresenter<TView : BaseView<TViewState>, TViewState: ViewState>(viewState: TViewState) : MviBasePresenter<TView, TViewState>(viewState) { protected val initialState: TViewState = viewState private var viewStateSnapshot: TViewState = viewState protected val lastViewState: TViewState get() = viewStateSnapshot override fun attachView(view: TView) { super.attachView(view) view.render(viewStateSnapshot) } override fun subscribeViewState(viewStateObservable: Observable<TViewState>, consumer: ViewStateConsumer<TView, TViewState>) { val viewStateStream = if(BuildConfig.DEBUG){ viewStateObservable } else { viewStateObservable.map { it as ViewState } .onErrorReturn { FailureViewState() }.filter { it !is FailureViewState } .map { it as TViewState } } super.subscribeViewState(viewStateStream) { view, viewState -> this.viewStateSnapshot = viewState consumer.accept(view, viewState) } } private class FailureViewState: ViewState() } After changing Unicast to Relay (as ValeriusGC suggest) state is not beeing updated anymore. — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#314?email_source=notifications&email_token=AAEOPLXML25TJBALTEUBZOTPYKBQDA5CNFSM4FB6S7PKYY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGODWXBVXQ#issuecomment-497949406>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAEOPLQRLI7ZGXQBMQRAS5DPYKBQDANCNFSM4FB6S7PA> .

[drbear95]

When can I expect a fix? It is critical for my app because i cannot update to AndroidX

[sockeqwe]

Not before next week Simon <[email protected]> schrieb am Mo., 3. Juni 2019, 10:16:

…

When can I expect a fix? It is critical for my app because i cannot update to AndroidX — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#314?email_source=notifications&email_token=AAEOPLTHAXDGMS6KLKBVEVTPYTHPNA5CNFSM4FB6S7PKYY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGODWYU2KA#issuecomment-498158888>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAEOPLVTVQDUL7NOZYE4L7DPYTHPNANCNFSM4FB6S7PA> .

[michalmatusiak]

@sockeqwe any news? when it will be fixed?

[sockeqwe]

No update yet sorry. Do you have custom subscription management somewhere in your presenter? Michal <[email protected]> schrieb am Mo., 15. Juli 2019, 14:18:

…

@sockeqwe <https://github.com/sockeqwe> any news? when it will be fixed? — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#314?email_source=notifications&email_token=AAEOPLSQJU3KLNH4DP76MOLP7RTKDA5CNFSM4FB6S7PKYY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGODZ5QLFA#issuecomment-511378836>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAEOPLTSP6ZS46IGJQC5NFTP7RTKDANCNFSM4FB6S7PA> .

[SunMaungOo]

@sockeqwe any update on the fix? I also got the same problem using AndroidX with version 3.1.1

[sockeqwe]

need to dedicate 1-2 weeks for it, not sure when I will have time for it Sun Maung Oo <[email protected]> schrieb am Mi., 18. Sep. 2019, 01:03:

…

@sockeqwe <https://github.com/sockeqwe> any update on the fix? I also got the same problem using AndroidX with version 3.1.1 — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#314?email_source=notifications&email_token=AAEOPLXUHAGLEC77BPG3NJDQKFO2ZA5CNFSM4FB6S7PKYY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOD66E55Y#issuecomment-532434679>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAEOPLSSRHTES5TIXGJRZCTQKFO2ZANCNFSM4FB6S7PA> .

[SunMaungOo]

@sockeqwe Just for your information , the solution provided by ValeriusGC which is changing it to ReplaySubject fix the problem. I don't know what effect it will have on other components but it fix the problem described.

[paul-wag]

Wish this had a solution.....