c++观察者模式收集

观察者模式

//
// Created by caozw on 17-9-27.
//
#ifndef _OBSERVER_H_
#define _OBSERVER_H_
#include <string>
#include <list>
#include <algorithm>
#include <string>
#include <iostream>

//观察者
class Observer
{
public:
    Observer() {}
    virtual ~Observer() {}
    virtual void Update() {}
};

//通知者
class CISubject
{
public:
    CISubject() {}
    virtual ~CISubject() {}
    void Attach(Observer *observer) { m_observers.push_back(observer); }     //添加观察者
    void Remove(Observer *observer) { m_observers.remove(observer); }        //移除观察者
    void Notify() //通知观察者
    {
        std::list<Observer*>::iterator iter = m_observers.begin();
        for(; iter != m_observers.end(); iter++)
            (*iter)->Update();
    }
    virtual void SetStatus(std::string s) { m_status = s; } //设置状态
    virtual std::string GetStatus() { return m_status; }    //获得状态
private:
    std::list<Observer* > m_observers; //观察者链表
protected:
    std::string m_status; //状态
};

//具体通知者
class Blog优快云 : public CISubject
{
private:
    std::string m_name; //博主名称
public:
    Blog优快云(std::string name): m_name(name) {}
    ~Blog优快云() {}
    void SetStatus(std::string s) { m_status = "优快云通知 : " + m_name + s; } //具体设置状态信息
    std::string GetStatus() { return m_status; }
};

//具体观察者
class ObserverBlog : public Observer
{
private:
    std::string m_name;  //观察者名称
    CISubject *m_blog;   //观察的博客，当然以链表形式更好，就可以观察多个博客
public:
    ObserverBlog(std::string name, CISubject *blog): m_name(name), m_blog(blog) {}
    ~ObserverBlog() {}
    void Update()  //获得更新状态
    {
        std::string status = m_blog->GetStatus();
        std::cout<<m_name<<"-------"<<status<< std::endl;
    }
};

#endif

实际使用例子：

#include <iostream>
#include "observer.h"

using namespace std;


int main()
{
    CISubject *blog = new Blog优快云("wuzhekai1985");
    Observer *observer1 = new ObserverBlog("tutupig", blog);
    blog->Attach(observer1);
    blog->SetStatus("发表设计模式C++实现（15）——观察者模式");
    blog->Notify();


    delete blog;
    delete observer1;
    return 0;
}