Signed apk crashes with facebook login

Question

My Signed apk crashes first time on facebook login with this error:

AndroidRuntime: FATAL Exception: main
com.facebook.aq: com.facebook.c.f got an unexpected method signature: public abstract com.facebook.c.c com.facebook.c.c.a(java.lang.Class)

However, it works fine with 2nd attempt login. I am using Facebook-android-sdk-3.6.0. I've checked here too - Android Facebook application crashes when using a hash key other than the debug hash key, but didn't find any solution.
Do anyone faced the same issue, please help me in sorting out the above problem.

Answer 1

I guess you're using proguard. Facebook SDK sources are open. No need to obfuscate them. We added this rule to our proguard.cfg file: -keep class com.facebook.** { *; }