我这里有个错误:
com.google.firebase.auth.FirebaseUser.getEmail()‘:试图在com.flipflop.flipflop_gmap.Utility.FirebaseMethods$1.onComplete(FirebaseMethods.java:63) at com.google.android.gms.tasks.zzj.run(未知源)的android.os.Handler.handleCallback( android.app.ActivityThread.main(ActivityT