初学设计模式之观察者模式

观察者模式代码例子

//观察者模式
#include<iostream>
#include<list>
using namespace std;

class MasterListener
{
public:
    virtual void OnChange()
    {
    };

};

class Student1:MasterListener
{
public:
     void OnChange()
    {
        cout<<"同学A不看小说了"<<endl;
    };
};


class Student2:MasterListener
{
public:
     void OnChange()
    {
        cout<<"同学B不玩手机了"<<endl;
    };
};


class Master
{
protected:
    list<MasterListener*>m_list;
    //MasterListener* m_MasterListenerPtr;
public:
    void setListener(MasterListener* m_MasterListenerPtr)
    {
        m_list.push_back(m_MasterListenerPtr);
        //m_MasterListenerPtr=m_MasterListener;
    };
    void Notify()
    {
        for(list<MasterListener*>::iterator iter=m_list.begin();iter!=m_list.end();iter++)
        {
            (*iter)->OnChange();
        };
    };
};

int main()
{
    Student1 *m_student1=new Student1;
    Student2 *m_student2=new Student2;
    Master m_master;
    m_master.setListener(m_student1);
    m_master.setListener(m_student2);

    cout<<"老师来了"<<endl;
    m_master.Notify();

    getchar();
    return 0;
};