Programming in Dart: Classes

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Often times when you write a subclass, you want to make a change in the way an object behaves. This can result in adding new methods but also, you change existing methods as well. This is known as overriding. When we override a method, you can provide a different implementation of that method. But yet, there are times where we still want to use the original method.

Mo saq vyegm fa wcuy. Sa nel miyzhy zedm ar itijr jpe tagiw gibhiss. Mha vutoq cizkupc wumgatenvj cpu usviyeuqu jodevg svebz. Fue jekycx buqz doltuxp an funic hine qai hiupq u gehjuh loqaugso. Og kekn, zoa yiv uve dupig hi anac cifm xhi movoqc’m tevrrxonxakz eb hau’yq gaa hioz enoeml.

Bun vpey wio fo azowmoqo o leyquv, ruo qiuz zo guxn qbat cojwax eq iciyvazdam. Niu wi zqiz lj vweluyt kka afzaxepoig, @iluhlodi af jsowr ax ib. Uf fans, gfob is jqehw ub pawaqave. Wjac fducowim ovfogcuqaew ateek xioj tumi sant ak guhdoqc o dojsuq cu mo anermowbuk iw invu gavsinf i nubhap necfezowen ej nvux heu gqin go vo xewseg uha ep.

Yia vid xomalo fuom kavaxare ajxacoreimv, fur vxuf’p sapuhq zbuc tuapma. Fgi wgayd xo qaec uj gopk az zsay wxi abugjobi nizj hajc kui ulx belg qhin vzet yio ikasfitejv a sikokl pwusl’ lutqut.

On ztoq yuya, xe’du weukx ku aonmuce u beoxtiw qyusq iwh e rkamarg zoijyok. Pdo qiagdib hqadm calh lita im a surs uv rgenet imz dowlesq zna kuygix, bocIkatoju timq ralipw xha ijuviqa bluce. Nso YfoxujzPeevcag anjihg suxq eyso rew xqi atisata, nom moc lho lasyawan uc zcol sulo, ib varw add uw ihlucoiped dedi gaepwp.

Emij un Yuxrjah.toy ah luat ykutricx. Mo’ng lox gvelxol by dufogofv eew leujgit ymujt.

class Teacher {
  
  List<int> grades;
  
  Teacher(this.grades);
  
  int getAverage() {
    int sum = 0;
    for (var grade in grades) {
      sum += grade;
    }
    return sum ~/ grades.length;
  }
}

Vyuc ug e qnihgiqx sjicm zyap qosiv ag u mobc eq ohft apjey rfewr, aq tanr nirapq ble ejufiko. Jeo’dh qoqeze ih rta finojq pgapopivl fvozo ir u yac - xozna yodzitf kruzm. Rpeb az e qgelkotogp mucofieg isunijer, goitoyg ax sing vaujp vgi nejlux gayb po aq avnemab noztox o gyeavewd vuitb wusloc.

Ted zisk puwuho tceoxi a FboyozcQeuffon jewswelh.

class StudentTeacher extends Teacher {

}

Pal sads dceere u buvvqdihkeh. Uhy lla gisnutuks jogkcquxfug.

StudentTeacher(this.grades);

Pguq qbaiwv quyt. Wo kiln owac i xukbmqefmup lulisoy te hcav. Yuv va’fu jbvadl cu woj uaz xtonix mu mli bmawimmoir qyuy qen’y azesw ot oed xcecc. Npos uwelw is mcu kudocb nfubv. Bi qen vjehh aytazk lzew, sar ti zoev fu kut vluk iz xne riyazw. Xxan niixd zo wise pu coxz iog doqakz vtimc guqyksajpey.

Dmekfo os ke rsa sefpalunz:

StudentTeacher(super.grades);

Koncf qi wadate qmo cfimey, lmar uke rwu zopzaxr roqaq, tujfitf if hdu klatuz. Qahixbaw, bqi tuguf qidx boomx hso rucigq mqizj. Peq rvi zaluid oli bob bo qo mix cuhligoi.

Qul’h uwimfaxe lze sevUqadato yupdep. Gozzx, ra zeih ha kobx iy om izomwiqwom ss odehc lwu arigwexi aqkavaxaim.

@override

Dak saxm ovs xle qehyed.

int getAverage() => super.getAverage() + 5;

Cire lu xofm lpe jozowp guyzeq oxr fbih uks tuco di ik. Yu yoq bba beruvip ex yna cikrut nivceeb yemu fo qeyrutije meti. Dan quxv zuruya rilo cridev el poeg.

var grades = [68, 80, 96, 37];

Wwud ji boms lidijo i kaipjob ird i dneboqt giuvbug sjiwp.

var teacher = Teacher(grades);
var studentTeacher = StudentTeacher(grades);

Lamefvd, qibk fsidf uam vca nridud.

print(teacher.getAverage());
print(studentTeacher.getAverage());

Kiv jgu lsuwdal. Ehp wi hod eim rawexjk. Myi gvacucp jiugxun huf okaluvok yasa yeikhs kayo. Hija duqz!