Multiple Table SQLite DB Adapter(s) in Android?

Question

I was reading the Android SQLite NotePad tutorial that referenced creating a DB Adapter class to create and access a DB table. When dealing with a multi-table SQLite Databa

Answer 1

Had the same problem, tried many solutions, finnaly i made an abstract method wich constructs the database structure and has extended class for the table classes.

This is my Database constructor class and is Abstract:

public abstract class dbAdapter {
    public static String DATABASE_NAME = "";
    public static final int DATABASE_VERSION = 1;
    public static final String DATABASE_TABLE1 = "ContactName";
    public static final String DATABASE_TABLE2 = "PhoneNumber";

    public static DbHelper ourHelper;
    public static Context ourContext;
    public static SQLiteDatabase ourDatabase;

    boolean ourConstructorBool = false;
    boolean ourDB = false;

    public static final String ContactNameTable = "CREATE TABLE "+DATABASE_TABLE1+" (" +
        ContactNameAdapter.KEY_ROWID+" INTEGER PRIMARY KEY AUTOINCREMENT, " +
        ContactNameAdapter.KEY_NAME+" TEXT, " +
        ContactNameAdapter.KEY_BIRTH_DATE+" TEXT);";

    public static final String PhoneNumberTable = "CREATE TABLE "+DATABASE_TABLE2+" (" + 
        PhoneNumberAdapter.KEY_NUMBER+" TEXT , " +
        PhoneNumberAdapter.KEY_DESCRIPTION+" TEXT, " +
        PhoneNumberAdapter.KEY_CONTACTID+" TEXT, " +
        "FOREIGN KEY(" + PhoneNumberAdapter.KEY_CONTACTID +") REFERENCES " +
        (ContactNameAdapter.DATABASE_TABLE)+"("+ContactNameAdapter.KEY_ROWID+") ON DELETE CASCADE"+
    ");";

    static class DbHelper extends SQLiteOpenHelper{
        public DbHelper(Context context) {
            super(context, DATABASE_NAME, null, DATABASE_VERSION);
        }
        @Override
        public void onCreate(SQLiteDatabase db) {
            db.execSQL(ContactNameTable);
            db.execSQL(PhoneNumberTable);
        }

        @Override
        public void onUpgrade(SQLiteDatabase db, int arg1, int arg2) {
            db.execSQL("DROP TABLE IF EXISTS " + ContactNameAdapter.DATABASE_TABLE);
            db.execSQL("DROP TABLE IF EXISTS " + PhoneNumberAdapter.DATABASE_TABLE);
            onCreate(db);
        }
    }

    public dbAdapter(Activity a){   
        if(!ourConstructorBool == true){
            ourContext = a;
            DATABASE_NAME = a.getString(Asaf.com.contactsEX.R.string.DB_NAME);
            ourConstructorBool = true;
        }
    }

    public dbAdapter open() throws SQLException{
        if(!ourDB == true){
            ourHelper = new DbHelper(ourContext);
            ourDB = true;
        }
        ourDatabase = ourHelper.getWritableDatabase();
        return this;
    }

    public void close(){
        if(ourDatabase.isOpen())
            ourHelper.close();
    }
}

And this is one of my table classes, the rest of the classes are implemented the same, just add as much as you like:

public class PhoneNumberAdapter extends dbAdapter{

    public static final String KEY_NUMBER = "PhoneNumber";
    public static final String KEY_DESCRIPTION = "Description";
    public static final String KEY_CONTACTID = "ContactName_id";

    public static final String DATABASE_TABLE = "PhoneNumber";

    public PhoneNumberAdapter(Activity a){
        super(a);
    }

    public long createEntry(String number, String description,long id){
        // TODO Auto-generated method stub
        ContentValues cv = new ContentValues();
        cv.put(KEY_NUMBER, number);
        cv.put(KEY_DESCRIPTION, description);
        cv.put(KEY_CONTACTID, id);
        return ourDatabase.insert(DATABASE_TABLE, null,cv);
    }
}

Hope I helped.