IllegalStateException: WorkManager is already initialized

Question

Having these dependencies:

dependencies {
    implementation "androidx.work:work-runtime:2.0.1"
    androidTestImplementation "androidx.work:work-testing:2.0.1"
}

When running this code for the second time:

Configuration config = new Configuration.Builder().build();
WorkManager.initialize(getApplicationContext(), config);

this.workManager = WorkManager.getInstance();

I get this error message:

java.lang.IllegalStateException: WorkManager is already initialized.
Did you try to initialize it manually without disabling WorkManagerInitializer?
See WorkManager#initialize(Context, Configuration) or the class level Javadoc for more information.

and it also throws a segmentation fault on the native side:

A/libc: Fatal signal 11 (SIGSEGV), code 1 (SEGV_MAPERR),
fault addr 0x878 in tid 10892 (ova.workmanager),
pid 10892 (ova.workmanager)

This would be the documentation for WorkManager#initialize(Context, Configuration).

---

The intent is to prevent the crash during manual initialization (in order to change the log level). How to disable the WorkManagerInitializer? If possible, I do not want to use the static keyword.

Answer 1

This is how to substitute provider androidx.work.impl.WorkManagerInitializer:

<application>
    ...

    <!-- disable default provider -->
    <provider
        android:name="androidx.work.impl.WorkManagerInitializer"
        android:authorities="${applicationId}.workmanager-init"
        android:exported="false"
        android:enabled="false"/>

    <!-- register custom provider -->
    <provider
        android:name=".CustomWorkManagerInitializer"
        android:authorities="${applicationId}.WorkManagerInit"/>

</application>

Source: Custom Work Manager initialization (in Kotlin).

---

Unless registering another provider, this gives a:

java.lang.IllegalStateException: WorkManager is not initialized properly. The most
likely cause is that you disabled WorkManagerInitializer in your manifest but forgot
to call WorkManager#initialize in your Application#onCreate or a ContentProvider.

And the ContentProvider registered in the src/debug/Manifest.xml:

public class WorkManagerInit extends ContentProvider {

    @Override
    public boolean onCreate() {
        if(getContext() != null) {
            Configuration config = new Configuration.Builder().build();
            WorkManager.initialize(getContext().getApplicationContext(), config);
        }
        return true;
    }
    ...
}

Answer 2

Since WorkManager 2.6, App Startup is used internally within WorkManager. To provide a custom initializer you need to remove the androidx.startup node.

If you don't use App Startup in your app, you can remove it completely.

<provider
    android:name="androidx.startup.InitializationProvider"
    android:authorities="${applicationId}.androidx-startup"
    tools:node="remove">
</provider>

Otherwise, remove only the WorkManagerInitializer node.

<provider
    android:name="androidx.startup.InitializationProvider"
    android:authorities="${applicationId}.androidx-startup"
    android:exported="false"
    tools:node="merge">

    <!-- If you are using androidx.startup to initialize other components -->
    <meta-data
        android:name="androidx.work.WorkManagerInitializer"
        android:value="androidx.startup"
        tools:node="remove" />
</provider>

While using a version of WorkManager older than 2.6, remove workmanager-init instead:

<provider
    android:name="androidx.work.impl.WorkManagerInitializer"
    android:authorities="${applicationId}.workmanager-init"
    tools:node="remove" />