java.util.ConcurrentModificationException in activity onCreate

Question

In a recent release where I added MoPub via Admob ad mediation I am seeing a bunch of ConcurrentModificationException in crash logs. It all seems to be native code and I am on the latest version of all ad related and google/android related libraries. Anyone run in to this before?

java.lang.RuntimeException:    at android.app.ActivityThread.performLaunchActivity (ActivityThread.java:3121)   at android.app.ActivityThread.handleLaunchActivity (ActivityThread.java:3264)   at android.app.servertransaction.LaunchActivityItem.execute (LaunchActivityItem.java:78)   at android.app.servertransaction.TransactionExecutor.executeCallbacks (TransactionExecutor.java:108)   at android.app.servertransaction.TransactionExecutor.execute (TransactionExecutor.java:68)   at android.app.ActivityThread$H.handleMessage (ActivityThread.java:1955)   at android.os.Handler.dispatchMessage (Handler.java:106)   at android.os.Looper.loop (Looper.java:214)   at android.app.ActivityThread.main (ActivityThread.java:7078)   at java.lang.reflect.Method.invoke (Native Method)   at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run (RuntimeInit.java:494)   at com.android.internal.os.ZygoteInit.main (ZygoteInit.java:964) Caused by: java.util.ConcurrentModificationException:    at androidx.c.g.put (SimpleArrayMap.java:482)   at com.google.android.gms.measurement.internal.hs.a   at com.google.android.gms.measurement.internal.hi.onActivityCreated   at android.app.Application.dispatchActivityCreated (Application.java:245)   at android.app.Activity.onCreate (Activity.java:1108)   at androidx.core.app.e.onCreate (ComponentActivity.java:81)   at androidx.activity.b.onCreate (ComponentActivity.java:149)   at androidx.fragment.app.c.onCreate (FragmentActivity.java:313)   at androidx.appcompat.app.e.onCreate (AppCompatActivity.java:106)   at com.teamtol.livedota.BaseActivity.onCreate (BaseActivity.java:21)   at com.teamtol.livedota.RecentGameActivity.onCreate (RecentGameActivity.java:70)   at android.app.Activity.performCreate (Activity.java:7327)   at android.app.Activity.performCreate (Activity.java:7318)   at android.app.Instrumentation.callActivityOnCreate (Instrumentation.java:1275)   at android.app.ActivityThread.performLaunchActivity (ActivityThread.java:3101) 

This is what the code looks like up to line 21 of BaseActivity:

protected void onCreate(Bundle savedInstanceState) {         supportRequestWindowFeature(Window.FEATURE_ACTION_BAR_OVERLAY);         super.onCreate(savedInstanceState); 

This is what the code looks like up to line 70 of RecentGameActivity

public class RecentGameActivity extends BaseActivity implements AdapterView.OnItemSelectedListener {     @Override     protected void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState); 

Answer 1

In our case, we are only seeing the crash with

com.google.firebase:firebase-analytics:17.2.2  

reverting to 17.2.1 has fixed the problem

This happens too if you are using firebase-core:17.2.2, because firebase-analytics is the same library rebranded. Take into account that as per official docs, current usage of firebase-core is deprecated -> https://firebase.google.com/support/release-notes/android#latest_sdk_versions

Answer 2

Revert your Firebase Core library to:

implementation 'com.google.firebase:firebase-core:17.1.0' 

I've seen this crash on both v17.2.1 and v17.2.2, but since reverting to 17.1.0 all has been fine.

I've reported the bug here: https://firebase.google.com/support/troubleshooter/report/bugs

Update

Thanks @Sébastien, reverting to v17.2.0 should also work:

implementation 'com.google.firebase:firebase-core:17.2.0'