Get the field value with a Cursor

Michaël picture Michaël · May 24, 2009 · Viewed 92.9k times · Source

I'm creating an application and I have problems with Cursor. I have an SQLiteDatabase that returns me a Cursor when I try to fetch the values with this function:

public Cursor fetchOption(long rowId) throws SQLException {

    Cursor mCursor = mDb.query(true, DATABASE_TABLE, new String[] {KEY_ROWID,
        KEY_TITLE, KEY_BODY}, KEY_ROWID + "=" + rowId, null,
        null, null, null, null);
    if (mCursor != null) {
        mCursor.moveToFirst();
    }
    return mCursor;

}

I don't know how to obtain the value of the field in the Cursor. If I do that like so:

String a = mOptionDb.fetchOption(0).getColumnName(0).toString();
String b = mOptionDb.fetchOption(0).getColumnName(1).toString();
String c = mOptionDb.fetchOption(0).getColumnName(2).toString();

I only obtain the name of the columns (_id, title, body) but not the values. Any suggestions on how to achieve this?

Answer

Mariano Kamp picture Mariano Kamp · May 24, 2009

I think you can forget about checking for null.

Instead check if there is data and then access the columns using the cursor:

Cursor cursor = fetchOption(0);

if (cursor.moveToFirst()) // data?
   System.out.println(cursor.getString(cursor.getColumnIndex("title")); 

cursor.close(); // that's important too, otherwise you're gonna leak cursors

It might also make sense to read an Android tutorial. The notepad tutorial seems to fit the bill: http://developer.android.com/guide/tutorials/notepad/index.html