persistChanges method is not working when table order is DESC

[vinit2209]

when i set private final String sort_order = "DESC "; // ASC or DESC

Below method is not working properly. item numbers are not getting saved correctly.

public void persistChanges() {
Cursor c = getCursor();
c.moveToPosition(-1);
while (c.moveToNext()) {
int listPos = getListPosition(c.getPosition());
if (listPos == REMOVED) {
mDbHelper
.deleteItemRecord(c.getInt(c.getColumnIndex("_id")));
} else if (listPos != c.getPosition()) {
mDbHelper.updateItemPosition(
c.getInt(c.getColumnIndex("_id")), listPos);
}
}
}

plz correct me if i am wrong

thnks
vinit