数据没有插入android中的Sqlite数据库

// 创建数据库和表
public class DBHelper extends SQLiteOpenHelper {
    private static final String DATABASE_NAME = "mydatabase.db";
    private static final int DATABASE_VERSION = 1;
    private static final String TABLE_NAME = "mytable";
    private static final String COLUMN_ID = "id";
    private static final String COLUMN_NAME = "name";

    public DBHelper(Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        String createTableQuery = "CREATE TABLE " + TABLE_NAME + " (" +
                COLUMN_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " +
                COLUMN_NAME + " TEXT)";
        db.execSQL(createTableQuery);
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        // 处理数据库升级逻辑
    }
}

// 插入数据
public class MainActivity extends AppCompatActivity {
    private DBHelper dbHelper;

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

        dbHelper = new DBHelper(this);
        SQLiteDatabase db = dbHelper.getWritableDatabase();

        ContentValues values = new ContentValues();
        values.put(DBHelper.COLUMN_NAME, "John Doe");

        long newRowId = db.insert(DBHelper.TABLE_NAME, null, values);

        if (newRowId != -1) {
            Toast.makeText(this, "Data inserted successfully", Toast.LENGTH_SHORT).show();
        } else {
            Toast.makeText(this, "Failed to insert data", Toast.LENGTH_SHORT).show();
        }

        db.close();
    }
}