signUp

package com.example.tiketsaya;

import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.LinearLayout;
import android.widget.Toast;

import com.google.firebase.database.DataSnapshot;
import com.google.firebase.database.DatabaseError;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;
import com.google.firebase.database.ValueEventListener;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;

public class RegisterOneActivity extends AppCompatActivity {

    LinearLayout btnBack;
    Button btnContinue;
    EditText username,password,email_address;
    DatabaseReference reference;

    String USERNAME_KEY = "usernamekey";
    String username_key = "";

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

        username = findViewById(R.id.username);
        password = findViewById(R.id.password);
        email_address = findViewById(R.id.email_address);

        btnBack = findViewById(R.id.btnBack);
        btnBack.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                onBackPressed();
            }
        });

        btnContinue = findViewById(R.id.btnContinue);
        btnContinue.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                //save to local
                SharedPreferences sharedPreferences = getSharedPreferences(USERNAME_KEY, MODE_PRIVATE);
                SharedPreferences.Editor editor = sharedPreferences.edit();
                editor.putString(username_key, username.getText().toString());
                editor.apply();
                //Toast.makeText(getApplicationContext(), "Username: " + username.getText().toString(), Toast.LENGTH_SHORT).show();

                //save to db
                reference = FirebaseDatabase.getInstance().getReference().child(username.getText().toString());
                reference.addListenerForSingleValueEvent(new ValueEventListener() {
                    @Override
                    public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
                        dataSnapshot.getRef().child("username").setValue(username.getText().toString());
                        dataSnapshot.getRef().child("password").setValue(password.getText().toString());
                        dataSnapshot.getRef().child("email_address").setValue(email_address.getText().toString());
                        dataSnapshot.getRef().child("user_balance").setValue(800);
                    }

                    @Override
                    public void onCancelled(@NonNull DatabaseError databaseError) {

                    }
                });

                Intent nextRegist = new Intent(RegisterOneActivity.this, RegisterTwoActivity.class);
                startActivity(nextRegist);
            }
        });
    }
}