Firebase Authui: Noclassdeffounderror: Failed Resolution Of: Lcom/google/android/gms/internal/zzbgl

My App crashes whenever I call this code: if (FirebaseAuth.getInstance().getCurrentUser() == null) { startActivityForResult( AuthUI.getInstance()

Solution 1:

Change this:

compile'com.firebaseui:firebase-ui-auth:3.3.0'

into this:

compile'com.firebaseui:firebase-ui-auth:4.0.0'

from the docs:

As of version 4.0.0, FirebaseUI has the following dependency versions:

Library Version
firebase-auth   16.0.1
play-services-auth  15.0.1
firebase-database   16.0.1
firebase-firestore  17.0.1
firebase-storage    16.0.1

more info here:

https://github.com/firebase/FirebaseUI-Android#dependencies

Solution 2:

I had same issue, after trying lots of things, this fixed this issue for me:

I modified my build.gradle on allProjects{} and added the following

allprojects {
  repositories {
    google()
    jcenter()
   //start here
    configurations.all {
        resolutionStrategy.eachDependency { DependencyResolveDetails details ->
            def requested = details.requested
            if (requested.group == 'com.google.android.gms') {
                details.useVersion '12.0.1'
            }
            if (requested.group == 'com.google.firebase') {
                details.useVersion '12.0.1'
            }
        }
    }
    //end
  }
}

source here