SQLite with Android Studio?

Question

I'm having problems creating sqlite database. I have searched some options but that didn't work out for me. Here is my code

MainActivity.java

public class MainActivity extends AppCompatActivity
{

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

        SQLiteDatabase db = new MyDBHelper(this).getWritableDatabase();
      }
    }

Database Helper

public class MyDBHelper extends SQLiteOpenHelper
    {
    public static final String DATABASE_NAME = "Student.db";
    public static final String TABLE_NAME = "student_table";
    public static final String COL_1 = "ID";
    public static final String COL_2 = "NAME";
    public static final String COL_3 = "SURNAME";
    public static final String COL_4 = "MARKS";

    public MyDBHelper(Context context)
    {
        super(context, DATABASE_NAME, null, 1);
        SQLiteDatabase db = getWritableDatabase();
    }

    @Override
    public void onCreate(SQLiteDatabase db)
    {
        db.execSQL("create table " + TABLE_NAME + " (ID INTEGER PRIMARY KEY 
        AUTOINCREMENT,NAME TEXT,SURNAME TEXT,MARKS INTEGER)");
    }

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

}

Thanks.

Answer 1

Your code is working fine but you need to insert data to your table then you can see the database.

MyDBHelper.java

public class MyDBHelper extends SQLiteOpenHelper
{
    public static final String DATABASE_NAME = "student";
    public static final String TABLE_NAME = "student_table";
    public static final String COL_1 = "ID";
    public static final String COL_2 = "NAME";
    public static final String COL_3 = "SURNAME";
    public static final String COL_4 = "MARKS";

    public MyDBHelper(Context context)
    {
        super(context, DATABASE_NAME, null, 1);
    }

    @Override
    public void onCreate(SQLiteDatabase db)
    {
        String query = "CREATE TABLE " + TABLE_NAME +
            "(" +
            COL_1 + " INTEGER PRIMARY KEY," +
            COL_2 + " TEXT," +
            COL_3 + " TEXT," +
            COL_4 + " TEXT" +
            ")";
        Log.e("query", query);
        db.execSQL(query);
    }

    public void addValue()
    {
        SQLiteDatabase db = this.getWritableDatabase();

        ContentValues values = new ContentValues();

        Random random = new Random();
        int randomValue = random.nextInt();

        values.put(COL_1, randomValue);
        //values.put(COL_1, 1001);
        values.put(COL_2, "Mitesh");
        values.put(COL_3, "Machhoya");
        values.put(COL_4, "80");

        // Inserting Row
        db.insert(TABLE_NAME, null, values);
        db.close(); // Closing database connection
    }

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

}

MainActivity.java

public class MainActivity extends AppCompatActivity
{
    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        MyDBHelper db = new MyDBHelper(this);
        db.addValue();
    }
}