observer.cpp

来自「23中设计模式大家都应该知道吧」· C++ 代码 · 共 80 行

//Observer.cpp
#include "Observer.h" 
#include "Subject.h"

#include <iostream> 
#include <string> 
using namespace std;

Observer::Observer() 
{ 
	_st = '\0';
}

Observer::~Observer() 
{
}

ConcreteObserverA::ConcreteObserverA(Subject* sub) 
{
	_sub = sub;
    _sub->Attach(this); 
}

ConcreteObserverA::~ConcreteObserverA() 
{
	_sub->Detach(this);
    if (_sub != 0) 
	{ 
		delete _sub; 
	} 
}

Subject* ConcreteObserverA::GetSubject() 
{ 
	return _sub; 
}

void ConcreteObserverA::PrintInfo() 
{ 
	cout<<"ConcreteObserverA observer.... "<<_sub->GetState()<<endl; 
}

void ConcreteObserverA::Update(Subject* sub) 
{ 
	_st = sub->GetState();
	PrintInfo(); 
}

ConcreteObserverB::ConcreteObserverB(Subject* sub) 
{ 
	_sub = sub;
    _sub->Attach(this); 
}

ConcreteObserverB::~ConcreteObserverB() 
{ 
	_sub->Detach(this);
    if (_sub != 0) 
	{ 
		delete _sub; 
	} 
}

Subject* ConcreteObserverB::GetSubject() 
{
	return _sub; 
}

void ConcreteObserverB::PrintInfo() 
{ 
	cout<<"ConcreteObserverB observer.... "<<_sub->GetState()<<endl; 
}

void ConcreteObserverB::Update(Subject* sub) 
{ 
	_st = sub->GetState();
    PrintInfo(); 
}