الدرس 47: شرح مفهوم الـ Mixin في لغة دارت (Mixin in Dart)

mixin Mixin1{
  // code 
}

mixin Mixin2{
  // code
}

class ClassName with Mixin1, Mixin2{
  // code 
}

mixin Mixin1 on Class1{
  // code
}

mixin ElectricVariant {
  void electricVariant() {
    print('This is an electric variant');
  }
}

mixin PetrolVariant {
  void petrolVariant() {
    print('This is a petrol variant');
  }
}

// كلمة with تستخدم لتطبيق الـ mixin على الكلاس
class Car with ElectricVariant, PetrolVariant {
  // هنا يمكن الوصول إلى الدوال electricVariant() و petrolVariant()  
}

void main() {
  var car = Car();
  car.electricVariant(); 
  car.petrolVariant();
}

This is an electric variant
This is a petrol variant

mixin CanFly {
  void fly() {
    print('I can fly');
  }
}

mixin CanWalk {
  void walk() {
    print('I can walk');
  } 
}

class Bird with CanFly, CanWalk {

}

class Human with CanWalk {

}

void main() {
  var bird = Bird();
  bird.fly();
  bird.walk();

  var human = Human();
  human.walk(); 
}

I can fly
I can walk
I can walk

abstract class Animal {
  // الخصائص
  String name;
  double speed;

  // الـ constructor
  Animal(this.name, this.speed);

  // الدالة المجردة
  void run(); 
}

// mixin CanRun تستخدم فقط مع كلاسات تورث Animal
mixin CanRun on Animal {
  // تنفيذ الدالة المجردة 
  @override
  void run() => print('$name is Running at speed $speed');
}

class Dog extends Animal with CanRun {
  // constructor
  Dog(String name, double speed) : super(name, speed); 
}

void main() {
  var dog = Dog('My Dog', 25);
  dog.run();
}

My Dog is Running at speed 25.0