Firebase Essentials - Android Edition was published on July 17, 2017. The current revision is 1.0. The revision of your copy of the book can be found in the copyright page at the start of the book.

Authentication Crashes when Signing Out of an Account

The FirebaseAuth app and other examples that use authentication may crash when signing out of an account with the following output in the Logcat panel:

FATAL EXCEPTION: main
java.lang.IncompatibleClassChangeError: 
Superclass com.google.android.gms.internal.zzbax of 
com.google.android.gms.internal.zzarm is an interface (declaration of 
'com.google.android.gms.internal.zzarm'

If you encounter this problem, edit the build.grade (Module: app) file located in the Project tool window under app -> Gradle Scripts and add the following line to the dependences section:

compile "com.google.android.gms:play-services-auth:11.0.4"

If you have encountered an issue with the book not listed above please contact us as at [email protected] and we will work to resolve the issue for you as quickly as possible.