Flutter勉強会3回目の資料(Mixin)

flutter_study_3rd_4.dart

void main() {
  Owl owl = Owl();
  print(owl.canFly);
  owl.fly();
  print(owl.canRun);
  owl.run();
  
  Dog dog = Dog();
  print(dog.canRun);
  dog.run();
}

mixin RunAbility {
  bool canRun = true;
  
  void run() {
    print('run run ru-');
  }
}

mixin FlyAbility on Bird {
  bool canFly = true;
  
  void fly() {
    print('I can flyyyyyyy!!!');
  }
}

abstract class Animal {
  String breed;

  void bark();
}

class Bird implements Animal {
  String breed = 'Bird';
  
  void bark() {
    print('cheep-cheep');
  }
}

// FlyAbilityはBird型の制約がついているのでBird型のsubclassにしか適用できない
class Owl extends Bird with FlyAbility, RunAbility {
  String breed = 'Owl';
  
  void bark() {
    print('Tu-wit tu-whoo');
  }
}

class Dog extends Animal with RunAbility {
  String breed = 'Dog';

  void bark() {
    print('bow-wow');
  }
}