SQLite Database Problems

 Main Activity Code

package com.apdim3.sqlite;

import android.database.Cursor;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

import androidx.appcompat.app.AppCompatActivity;

import com.apdim3.sqlite.simple.SimpleDbHelper;
import com.google.android.material.bottomsheet.BottomSheetDialog;
import com.google.android.material.floatingactionbutton.FloatingActionButton;

public class MainActivity extends AppCompatActivity {

    TextView tvDisplay;
    SimpleDbHelper dbHelper;
    FloatingActionButton addNewData;

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

        dbHelper = new SimpleDbHelper(MainActivity.this);
        tvDisplay = findViewById(R.id.tvDisplay);
        addNewData = findViewById(R.id.addNewData);

        addNewData.setOnClickListener(v -> { showDialog(); });


        showAllData();
    }

    private void showDialog(){
        View view = LayoutInflater.from(this).inflate(R.layout.data_insert_dialog, null);
        BottomSheetDialog dialog = new BottomSheetDialog(this);
        dialog.setContentView(view);

        EditText edName, edEmail;
        Button btnInsert;

        edName = view.findViewById(R.id.edName);
        edEmail = view.findViewById(R.id.edEmail);
        btnInsert = view.findViewById(R.id.btnInsert);

        btnInsert.setOnClickListener(v -> {
            String name = edName.getText().toString();
            String email = edEmail.getText().toString();

            dbHelper.insertData(name, email);

            dialog.dismiss();
            Toast.makeText(this, "Data has been Inserted", Toast.LENGTH_SHORT).show();
            showAllData();
        });

        dialog.show();
    }

    private void showAllData(){
        Cursor cursor = dbHelper.getAllData();
        tvDisplay.setText("Total Data: " + cursor.getCount());

        while (cursor.moveToNext()){
            int id = cursor.getInt(0);
            String name = cursor.getString(1);
            String email = cursor.getString(2);

            tvDisplay.append("\nID: " + id);
            tvDisplay.append("\nName: " + name);
            tvDisplay.append("\nEmail: " + email + "\n");
        }
    }
}

Database Helper code

package com.apdim3.sqlite.simple;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;

import androidx.annotation.Nullable;

public class SimpleDbHelper extends SQLiteOpenHelper {
    public static final String DB_NAME = "my_database";
    public static final int DB_VERSION = 1;


    public SimpleDbHelper(@Nullable Context context) {
        super(context, DB_NAME, null, DB_VERSION);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL("CREATE TABLE my_table (id INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT, email TEXT)");
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        db.execSQL("DROP TABLE IF EXISTS my_table");

    }

    public void insertData(String name, String email){
        SQLiteDatabase db = this.getWritableDatabase();
        ContentValues conVal = new ContentValues();
        conVal.put("name", name);
        conVal.put("email", email);
        db.insert("my_table", null, conVal);
    }

    public Cursor getAllData(){
        SQLiteDatabase db = this.getReadableDatabase();
        Cursor cursor = db.rawQuery("SELECT * FROM my_table", null);
        return cursor;
    }
}