策略模式（strategy）

#include <iostream>
using namespace std;

//设计思想：我们父类和子类就是一个扩展的关系？是不是合适
//里氏代换原则：子类对象就应该能完全替代父类的行为
//对于继承这样设计，特别小心，我们：组合大于继承
//把quack和fly抽象成为一个对象，那么这个问题就了解决方案


//////////////////////////
//完成了将“动作”抽象成“对象”
class QuackBehavior {
public:
    virtual void quack() = 0;
protected:
    QuackBehavior(){} 
};
class FlyBehavior {
public:
    virtual void fly() = 0;
protected:
    FlyBehavior(){}
};

class FlyWithRocket :public FlyBehavior {
    void fly() {
        cout << "做着火箭飞" << endl;
    }
};

class FlyWithWings :public FlyBehavior {
    void fly() {
        cout << "我有翅膀可以自己飞" << endl;
    }
};

class FlyWithNoWay :public FlyBehavior {
    void fly() {
        cout << "我根本就会飞" << endl;
    }
};

class ZhiZhiQuack :public QuackBehavior {
public:    void quack() {
    cout << "吱吱" << endl;
    }
};

class PersonQuack :public QuackBehavior {
public:
    void quack() {
        cout << "我是唐唐姥姥" << endl;
    }
};

class WigeonQuack :public QuackBehavior {
public:
    void quack() {
        cout << "丑小鸭变天鹅" << endl;
    }
};

/////////////////////////////////////
//Duck has a Quack 
//     has a Fly
class Duck {

public:
    
    virtual void Display() = 0;
    void setFlyBehavior(FlyBehavior* fb) {
        m_pFly = fb;
    }
    void setQuackBehavior(QuackBehavior* qb) {
        m_pQuack = qb;
    }

    virtual void perfomrFly() {
        m_pFly->fly();

        //if (is 唐老鸭） {唐老鸭的飞行
        //if (is 小黄鸭）{小黄鸭的飞行.....
    }

    virtual void performQuack() {
        m_pQuack->quack();
    }
protected:
    QuackBehavior *m_pQuack;
    FlyBehavior *m_pFly;
private:
};
//DonaladDuck is Duck
class DonaladDuck :public Duck {
public:
    DonaladDuck() {
        m_pFly = new FlyWithRocket;//某一个FlyBehavior的实例
        m_pQuack = new PersonQuack();
    }
    void Display() {
        perfomrFly();
        performQuack();
    }
    
};
//第一个困境：子类似乎不太那么像父类。。。
class RuberDuck : public Duck {
public:
    RuberDuck() {
        m_pFly = new FlyWithNoWay();
        m_pQuack = new ZhiZhiQuack();
    }
    void Display() {
        perfomrFly();
        performQuack();
    }
};

class WigeonDuck : public Duck {
public:
    WigeonDuck() {
        m_pFly = new FlyWithWings;
        m_pQuack = new WigeonQuack;
    }
    void Display() {
        perfomrFly();
        performQuack();
    }
    
};

int main() {
    DonaladDuck *pDonlad = new DonaladDuck;
    pDonlad->Display();
    system("pause");
    return 0;
}
//
class XiaoFeiXia :public Duck {
    //
    //m_pFly = new FlyWithHotPollun()
};