how to solve Unable to find explicit activity in firebase AuthUi?

Issue

While working with firebase UI I am getting Unable to find explicit activity class com.firebase.ui.auth.KickoffActivity

 protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    FirebaseApp.initializeApp(this);
    setContentView(R.layout.activity_main);
    FirebaseApp.initializeApp(this);
    mAuth=FirebaseAuth.getInstance();
    mAuthListner=new FirebaseAuth.AuthStateListener() {
        @Override
        public void onAuthStateChanged(@NonNull FirebaseAuth firebaseAuth) {
            FirebaseUser user=firebaseAuth.getCurrentUser();
            if(user!=null){
                Toast.makeText(getApplicationContext(),"Sign in success",Toast.LENGTH_SHORT).show();

            }
            else {
                startActivityForResult(AuthUI.getInstance()
                        .createSignInIntentBuilder()
                        .setIsSmartLockEnabled(false)
                        .setProviders(AuthUI.EMAIL_PROVIDER,AuthUI.GOOGLE_PROVIDER).build(),
                        RC_SIGN_IN);
            }
        }
    };
}

Full error message

android.content.ActivityNotFoundException: Unable to find explicit activity class {com.example.flamanco.trackme/com.firebase.ui.auth.KickoffActivity}; have you declared this activity in your AndroidManifest.xml? at android.app.Instrumentation.checkStartActivityResult

Added dependencies on app/.gradle file

dependencies {
    compile fileTree(include: ['*.jar'], dir: 'libs')
    testCompile 'junit:junit:4.12'
    compile 'com.android.support:appcompat-v7:24.2.1'
    compile 'com.google.firebase:firebase-core:10.0.1'
    compile 'com.google.firebase:firebase-auth:10.0.1'
    compile 'com.firebaseui:firebase-ui-auth:1.1.1'
}

apply plugin: 'com.google.gms.google-services'

also added plugin in build gradle

classpath 'com.google.gms:google-services:3.0.0'

Finally I did added SHA1 fingerprint in my firebase console project.

Do I need to add auth.kickOff activity in manifest file

Solution

Finally I have completely reinstall android studio to latest version, updated everything including

• Google play service
• firebase libraries
• gradle version
• google repositoris

And I started new project from begining and worked with no error. there are many activities that are added automatically on adding AUTHUI dependencies. these activity includes kickoffactivity,recoverpasswordactivity,registerEmailActivity,etc I can verify if by going to path

/project/module/build/intermediates/manifests/full/debug/And‌​roidManifest.xml.

previously i don't have kickoffactivity in this manifest file, I don't know the reason,but now i have it.I don't think adding it manually on app's manifest file will work.

Answered By - Kharak