EditText username, fullname, email, password, password2;
Button register;
TextView txt_login;

private static final int RC_SIGN_IN = 9001;
private GoogleApiClient mGoogleApiClient;
FirebaseAuth auth, mAuth;

DatabaseReference reference, reference2;
ProgressDialog pd;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_register);



    username = findViewById(R.id.username);
    email = findViewById(R.id.email);
    fullname = findViewById(R.id.fullname);
    password = findViewById(R.id.password);
    password2 = findViewById(R.id.password2);
    register = findViewById(R.id.register);
    txt_login = findViewById(R.id.txt_login);

    auth = FirebaseAuth.getInstance();
    mAuth = FirebaseAuth.getInstance();

    txt_login.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            startActivity(new Intent(RegisterActivity.this, LoginActivity.class));
        }
    });

    register.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            pd = new ProgressDialog(RegisterActivity.this);
            pd.setMessage("Please wait...");
            pd.show();

            String str_username = username.getText().toString();
            String str_fullname = fullname.getText().toString();
            String str_email = email.getText().toString();
            String str_password = password.getText().toString();
            String str_password2 = password2.getText().toString();

            if (TextUtils.isEmpty(str_username) || TextUtils.isEmpty(str_fullname) || TextUtils.isEmpty(str_email) || TextUtils.isEmpty(str_password) || TextUtils.isEmpty(str_password2)){
                pd.dismiss();
                Toast.makeText(RegisterActivity.this, "All fields are required!", Toast.LENGTH_SHORT).show();
            } else if(str_password.length() < 6){
                pd.dismiss();
                Toast.makeText(RegisterActivity.this, "Password must have 6 characters!", Toast.LENGTH_SHORT).show();
            }else if(!str_password.equals(str_password2)){
                pd.dismiss();
                Toast.makeText(RegisterActivity.this, "Passwords does not match", Toast.LENGTH_SHORT).show();
            } else {
                register(str_username, str_fullname, str_email, str_password);
            }
        }
    });

//google login

    GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
            .requestIdToken(getString(R.string.default_web_client_id))
            .requestEmail()
            .build();

    mGoogleApiClient = new GoogleApiClient.Builder(this)
            .enableAutoManage(this, this)
            .addApi(Auth.GOOGLE_SIGN_IN_API, gso)
            .build();

    SignInButton button = (SignInButton) findViewById(R.id.GoogleLogin);
    button.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Intent signInIntent = Auth.GoogleSignInApi.getSignInIntent(mGoogleApiClient);
            startActivityForResult(signInIntent, RC_SIGN_IN);
        }
    });

@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);

    // Result returned from launching the Intent from GoogleSignInApi.getSignInIntent(...);
    if (requestCode == RC_SIGN_IN) {
        GoogleSignInResult result = Auth.GoogleSignInApi.getSignInResultFromIntent(data);
        if (result.isSuccess()) {
            // Google Sign In was successful, authenticate with Firebase
            GoogleSignInAccount account = result.getSignInAccount();
            firebaseAuthWithGoogle(account);
        } else {
            // Google Sign In failed, update UI appropriately
            // ...
        }
    }
}



private void firebaseAuthWithGoogle (GoogleSignInAccount acct){
    AuthCredential credential = GoogleAuthProvider.getCredential(acct.getIdToken(), null);
    mAuth.signInWithCredential(credential)
            .addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
                @Override
                public void onComplete(@NonNull Task<AuthResult> task) {
                    if (task.isSuccessful()) {
                        FirebaseUser firebaseUser = mAuth.getCurrentUser();
                        String userID = firebaseUser.getUid();

                        reference = FirebaseDatabase.getInstance().getReference().child("Users").child(userID);
                        HashMap<String, Object> map = new HashMap<>();
                        map.put("id", userID);
                        map.put("username", username);
                        map.put("fullname", fullname);
                        map.put("imageurl", "https://firebasestorage.googleapis.com/v0/b/instagramtest-fcbef.appspot.com/o/placeholder.png?alt=media&token=b09b809d-a5f8-499b-9563-5252262e9a49");
                        map.put("bio", "");
                        reference.setValue(map).addOnCompleteListener(new OnCompleteListener<Void>() {
                            @Override
                            public void onComplete(@NonNull Task<Void> task) {
                                if (task.isSuccessful()){
                                    pd.dismiss();
                                    Intent intent = new Intent(RegisterActivity.this, MainActivity.class);
                                    intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK | Intent.FLAG_ACTIVITY_NEW_TASK);
                                    startActivity(intent);
                                }
                            }
                        });
                    } else {
                        // If sign in fails, display a message to the user.
                        //Log.w(TAG, "signInWithCredential:failure", task.getException());
                        // Toast.makeText(GoogleSignInActivity.this, "Authentication failed.",
                        //          Toast.LENGTH_SHORT).show();
                        //  updateUI(null);
                    }

                    // ...
                }
            });
}


@Override
public void onConnectionFailed (@NonNull ConnectionResult connectionResult){

}

java.lang.NoSuchMethodError: No virtual method zzbqo()Z in class Lcom/google/firebase/FirebaseApp; or its super classes (declaration of 'com.google.firebase.FirebaseApp' appears in /data/app/com.devkang.instagramtest-0yUpiRLjYo6Yjvmds4v0zA==/split_lib_dependencies_apk.apk)