#include "stdafx.h"
#include <boost/shared_ptr.hpp>
#include <boost/make_shared.hpp>
#include <string>
#include <iostream>
#include <boost/format.hpp>
#include <boost/enable_shared_from_this.hpp>
using namespace boost;
class Context;
class State
{
public:
virtual void Operation(shared_ptr<Context>) = 0;
virtual void ChangeState(shared_ptr<Context>,shared_ptr<State>) = 0;
virtual void OperationAndChangeState(shared_ptr<Context>) = 0;
};
class Context : public enable_shared_from_this<Context>
{
public:
Context(){}
virtual ~Context(){}
void setState(shared_ptr<State> state)
{
_m_ptrState = state;
}
shared_ptr<State> getState()
{
return _m_ptrState;
}
//某种状态对应的操作
void Operation1()
{
std::cout << "Operation1 Finished." << std::endl;
}
void Operation2()
{
std::cout << "Operation2 Finished." << std::endl;
}
void Operation3()
{
std::cout << "Operation3 Finished." << std::endl;
}
void OperationState()
{
_m_ptrState->OperationAndChangeState(shared_from_this());
}
protected:
shared_ptr<State> _m_ptrState;
friend class State;
};
class StateC : public State
{
public:
virtual void Operation(shared_ptr<Context> context)
{
context->Operation3();
}
virtual void ChangeState(shared_ptr<Context> context,shared_ptr<State> state)
{
context->setState(state);
}
virtual void OperationAndChangeState(shared_ptr<Context> context)
{
context->Operation3();
auto state = make_shared<StateC>();
ChangeState(context,state);
}
};
class StateB : public State
{
public:
virtual void Operation(shared_ptr<Context> context)
{
context->Operation2();
}
virtual void ChangeState(shared_ptr<Context> context,shared_ptr<State> state)
{
context->setState(state);
}
virtual void OperationAndChangeState(shared_ptr<Context> context)
{
context->Operation2();
auto state = make_shared<StateC>();
ChangeState(context,state);
}
};
//StateA
class StateA : public State
{
public:
virtual void Operation(shared_ptr<Context> context)
{
context->Operation1();
}
virtual void ChangeState(shared_ptr<Context> context,shared_ptr<State> state)
{
context->setState(state);
}
virtual void OperationAndChangeState(shared_ptr<Context> context)
{
context->Operation1();
auto state = make_shared<StateB>();
ChangeState(context,state);
}
};
void testStateMode()
{
shared_ptr<Context> context = make_shared<Context>();
auto stateA = make_shared<StateA>();
auto stateB = make_shared<StateB>();
auto stateC = make_shared<StateC>();
context->setState(stateA);
context->OperationState();
context->OperationState();
context->OperationState();
}