עבודה עם SQLite

public class CustomerModel {
    private int id;
    private String name;
    private int age;
    private boolean isActive;

    public CustomerModel(int id, String name, int age, boolean isActive) {
        this.id = id;
        this.name = name;
        this.age = age;
        this.isActive = isActive;
    }

    public CustomerModel() { }

    public int getId() { return id; }
    public String getName() { return name; }
    public int getAge() { return age; }
    public boolean isActive() { return isActive; }

    public void setId(int id) { this.id = id; }
    public void setName(String name) { this.name = name; }
    public void setAge(int age) { this.age = age; }
    public void setActive(boolean active) { isActive = active; }

    @Override
    public String toString() {
        return "CustomerModel{" +
               "id=" + id +
               ", name='" + name + '\'' +
               ", age=" + age +
               ", isActive=" + isActive +
               '}';
    }
}

public class MainActivity extends AppCompatActivity {

    Button add, viewAll;
    EditText customerName, age;
    Switch swActive;
    ListView customersList;

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

        add = findViewById(R.id.add);
        viewAll = findViewById(R.id.viewAll);
        age = findViewById(R.id.age);
        customerName = findViewById(R.id.customerName);
        swActive = findViewById(R.id.swActive);
        customersList = findViewById(R.id.customersList);

        add.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                CustomerModel customerModel1;
                try {
                    customerModel1 = new CustomerModel(-1,
                        customerName.getText().toString(),
                        Integer.parseInt(age.getText().toString()),
                        swActive.isChecked());
                    Toast.makeText(MainActivity.this, customerModel1.getName(), Toast.LENGTH_SHORT).show();
                } catch (Exception e) {
                    Toast.makeText(MainActivity.this, "invalid age insered", Toast.LENGTH_SHORT).show();
                }
            }
        });

        viewAll.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Toast.makeText(MainActivity.this, "View ALL CLICKED", Toast.LENGTH_SHORT).show();
            }
        });
    }
}

public class DataBaseHelper extends SQLiteOpenHelper {

    private static final String DATABASENAME = "customers.db";
    private static final String TABLE_RECORD = "tblresult";
    private static final int DATABASEVERSION = 1;

    private static final String COLUMN_ID = "_id";
    private static final String COLUMN_NAME = "name";
    private static final String COLUMN_AGE = "age";
    private static final String COLUMN_ACTIVE = "isActive";

    private static final String CREATE_TABLE_USER = "CREATE TABLE IF NOT EXISTS " +
            TABLE_RECORD + "(" +
            COLUMN_ID + " INTEGER PRIMARY KEY AUTOINCREMENT," +
            COLUMN_NAME + " TEXT," +
            COLUMN_AGE + " INT," +
            COLUMN_ACTIVE + " BOOL) ";

    private static final String[] allColumns = {COLUMN_ID, COLUMN_NAME, COLUMN_AGE, COLUMN_ACTIVE};

    public DataBaseHelper(@Nullable Context context) {
        super(context, "customers.db", null, 1);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL(CREATE_TABLE_USER);
    }

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

DataBaseHelper dataBaseHelper = new DataBaseHelper(MainActivity.this);

add.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        CustomerModel customerModel1;
        try {
            customerModel1 = new CustomerModel(-1,
                customerName.getText().toString(),
                Integer.parseInt(age.getText().toString()),
                swActive.isChecked());
        } catch (Exception e) {
            customerModel1 = new CustomerModel(-1, "error", 0, false);
        }

        DataBaseHelper dataBaseHelper = new DataBaseHelper(MainActivity.this);
        boolean success = dataBaseHelper.addOne(customerModel1);
        Toast.makeText(MainActivity.this, "Success is: " + success, Toast.LENGTH_SHORT).show();
    }
});

import android.database.sqlite.SQLiteOpenHelper;

public boolean addOne(CustomerModel customerModel) {
    SQLiteDatabase db = this.getWritableDatabase();
    ContentValues cv = new ContentValues();

    cv.put(COLUMN_NAME, customerModel.getName());
    cv.put(COLUMN_AGE, customerModel.getAge());
    cv.put(COLUMN_ACTIVE, customerModel.isActive());

    long insert = db.insert(TABLE_RECORD, null, cv);
    return insert != -1;
}

public List<CustomerModel> getEveryone() {
    List<CustomerModel> returnList = new ArrayList<>();
    String queryString = "SELECT * FROM " + TABLE_RECORD;
    SQLiteDatabase db = this.getReadableDatabase();
    Cursor cursor = db.rawQuery(queryString, null);

    if (cursor.moveToFirst()) {
        do {
            int id = cursor.getInt(0);
            String name = cursor.getString(1);
            int age = cursor.getInt(2);
            boolean active = cursor.getInt(3) == 1;
            CustomerModel newCustomer = new CustomerModel(id, name, age, active);
            returnList.add(newCustomer);
        } while (cursor.moveToNext());
    }

    cursor.close();
    db.close();
    return returnList;
}

viewAll.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        DataBaseHelper dataBaseHelper = new DataBaseHelper(MainActivity.this);
        List<CustomerModel> everyone = dataBaseHelper.getEveryone();

        ArrayAdapter customerArrayAdapter = new ArrayAdapter<>(
            MainActivity.this,
            android.R.layout.simple_list_item_1,
            everyone);

        customersList.setAdapter(customerArrayAdapter);
    }
});