Android开发中谁用过SimpleCursorTreeAdapter？求指教啊！我是实在GOOGLE不到才来这问的

哪位大神用过呢？
要重写getChildrenCursor()怎么也写不对。。。


@Override
protected Cursor getChildrenCursor(Cursor groupCursor) {
mGroupIdColumnIndex = groupCursor.getColumnIndexOrThrow(RecordStorage.KEY_ID);
String groupId = groupCursor.getLong(mGroupIdColumnIndex) + "";

return rLocalUtils.getChildCursorByID(groupId);
}



public Cursor getChildCursorByID(String id) {
db = mSQLHelper.getReadableDatabase();
String selection = KEY_ID + " =? AND " + KEY_DELETED + " =? AND " + KEY_HIDDEN + " =? ";
String[] selectionArgs = { id, "0", "0" };
Cursor cursor;
cursor = db.query(RECORDS_TABLE_NAME, new String[] {KEY_DATE, KEY_TAGS, KEY_NOTE}, selection, selectionArgs,
null, null, KEY_DATE + " DESC");
return cursor;
}