Unable to initialize NavBackStackEntry - IllegalStateException: Method addObserver must be called on the main thread [171125856]

Fixed

Bug

Status Update

No update yet.

Description

[Deleted User]

created issue #1

Oct 19, 2020 08:57AM

Component used: Navigation

Version used: 2.2.0, 2.3.0, 2.3.1

Devices/Android versions reproduced on: 10.0, 9.0 - probably not related

Description:

I've updated two dependencies in my project:

androidx.fragment:fragment 1.3.0-alpha06 -> 1.3.0-beta01
androidx.activity.activity 1.1.0 -> 1.2.0-beta01

and now I see that NavController::navigate needs to be called from the main thread. Otherwise NavBackStackEntry throws IllegalStateException when trying to register lifecycle observer.

Stacktrace:

Caused by: java.lang.IllegalStateException: Method addObserver must be called on the main thread
    at androidx.lifecycle.LifecycleRegistry.enforceMainThreadIfNeeded(LifecycleRegistry.java:317)
    at androidx.lifecycle.LifecycleRegistry.addObserver(LifecycleRegistry.java:172)
    at androidx.savedstate.SavedStateRegistryController.performRestore(SavedStateRegistryController.java:61)
    at androidx.navigation.NavBackStackEntry.<init>(NavBackStackEntry.java:84)
    at androidx.navigation.NavBackStackEntry.<init>(NavBackStackEntry.java:69)
    at androidx.navigation.NavController.navigate(NavController.java:970)
    at androidx.navigation.NavController.navigate(NavController.java:867)

There were no changes in documentation so I assume that this behavior is unintended.

Comments

il...@google.com <il...@google.com> #2Oct 19, 2020 08:10PM

After creating the issue I've noticed that I mixed up a few terms, sorry about that. JobService should be JobScheduler. When referring to jobs in the description, those are classes extending Worker.

[Deleted User] <[Deleted User]> #3Oct 20, 2020 07:19AM

We have a large set of users seeing this same issue... I can confirm that it seems to only effect users using Android OS 4.4 - 5.1. We are also using WorkManager 2.0.0

ap...@google.com <ap...@google.com> #4Apr 6, 2021 10:13PM

Project: platform/frameworks/support
Branch: androidx-master-dev

commit 098c163581a360c32baa6e4c215227f0efd10889
Author: Rahul Ravikumar <rahulrav@google.com>
Date: Mon Mar 25 14:05:34 2019

Reset WorkConstraintsTracker when cleaning up in DelayMetCommandHandler.

* DelayMetCommandHandler would previously not cleanup correctly and WorkConstraintsTracker
would trigger callbacks without going through the SystemAlarmDispatcher lifecycle
of processing a command.

Fixes:

b/129226383

Test: Added a unit test.
Change-Id: Id2aaf0cce7c4a1a4526a25a211f3fe0551dbe557

M work/workmanager/src/androidTest/java/androidx/work/impl/background/systemalarm/SystemAlarmDispatcherTest.java
M work/workmanager/src/main/java/androidx/work/impl/background/systemalarm/DelayMetCommandHandler.java

https://android-review.googlesource.com/933140

https://goto.google.com/android-sha1/098c163581a360c32baa6e4c215227f0efd10889

il...@google.com <il...@google.com> #5Apr 6, 2021 10:17PM

Marked as fixed, reassigned to il...@google.com.

Great to see such a quick fix. Do you have any estimate when a new version that includes this change will be released?

ap...@google.com <ap...@google.com> #6Apr 12, 2021 11:58PM

It should be available in the next 2.x.x version.

Issue 171125856