How to make a user sign out in Firebase?

Question

I am making a simple authentication app in Android using Firebase authentication. Till now I am successful in signing the user in, however the issue is that the user remains

Answer 1

if you are using firebaseAuthUI then recommended method is

public void onClick(View v) {
if (v.getId() == R.id.sign_out) {
    AuthUI.getInstance()
        .signOut(this)
        .addOnCompleteListener(new OnCompleteListener() {
            public void onComplete(@NonNull Task task) {
                // user is now signed out
                startActivity(new Intent(MyActivity.this, SignInActivity.class));
                finish();
            }
        });
    }
}

according to firebaseAuthUI github Guide.