public List<District> GetAllDistrict() { var cursor = db.abc (); List<District> list = new List<District> (); list.Add (new District { name = "Chọn quận", }); list [0].addChild (new Ward{ name = "Chọn phường" }); if (cursor.MoveToFirst ()) { for (int i = 0; i < cursor.Count; i++) { int id = cursor.GetInt (cursor.GetColumnIndex (District.ID_COLUMN)); string name = cursor.GetString (cursor.GetColumnIndex (District.NAME_COLUMN)); District item = new District{ id = id, name = name }; var cursorWard = db.GetWardFromDistrictID (id); if (cursorWard.MoveToFirst ()) { item.addChild (new Ward{ name = "Chọn phường" }); for (int j = 0; j < cursorWard.Count; j++) { item.addChild ( new Ward { id = cursorWard.GetInt (cursor.GetColumnIndex (Ward.ID_COLUMN)), name = cursorWard.GetString (cursor.GetColumnIndex (Ward.NAME_COLUMN)), districtParent = item }); cursorWard.MoveToNext (); } } else { item.addChild (new Ward{ name = "Không tìm thấy" }); } list.Add (item); cursor.MoveToNext (); } return list; } return list; }