brief introduction

Bridge: separate the abstract from its implementation so that they can all change independently.

Effect

To solve the problem of more and more complex classes and inflexible extension when there are many possible changes.

Application scenario

If there are more than one dimension changes in the design, we can use the bridge mode. If only one dimension is changing, then we can use inheritance to solve the problem successfully.

The code is as follows:

#include <iostream>
#include <string>
#include <memory>

///////////////////////////////////////
//Software base class
class software
{
public:
    software(void){}
    virtual ~software(void){}

public:
    virtual void opt(void) = 0;
};
//Mobile phone base class
class mobilephone
{
public:
    mobilephone(void){}
    virtual ~mobilephone(void){}

public:
    virtual void opt() = 0;
};
class mobilephone_sw
{
public:
    mobilephone_sw(std::shared_ptr<software> sw)
		: m_software(sw)
	{
			
	}
    virtual ~mobilephone_sw(void){}

public:
    virtual void opt() = 0;
	std::shared_ptr<software> m_software;
};
///////////////////////////////////////
//IPhone
class iphone : public mobilephone_sw
{
public:
    iphone(std::shared_ptr<software> sw) : mobilephone_sw(sw){}
    virtual ~iphone(void){}

public:
    void opt(void)
	{
		std::cout << "opt : this is iphone" << std::endl;
		m_software->opt();
	}
};
//HUAWEI mobile phone
class huawei : public mobilephone_sw
{
public:
    huawei(std::shared_ptr<software> sw): mobilephone_sw(sw){}
    virtual ~huawei(void){}

public:
    void opt(void)
	{
		std::cout << "opt : this is huawei" << std::endl;
		m_software->opt();
	}

};
///////////////////////////////////////
//Software: glory of the king
class wangzhe : public software
{
public:
    wangzhe(void){}
    virtual ~wangzhe(void){}

public:
    virtual void opt(void)
	{
		std::cout << "opt : Glory of Kings!" << std::endl;
	}
};
//Software: Taobao
class taobao : public software
{
public:
    taobao(void){}
    virtual ~taobao(void){}

public:
    virtual void opt(void)
	{
		std::cout << "opt : TaoBao!" << std::endl;
	}
};
///////////////////////////////////////
int main()
{
	std::cout << "start-up .." << std::endl;
	std::shared_ptr<wangzhe> p_wz = std::make_shared<wangzhe>();
	std::shared_ptr<taobao>  p_tb = std::make_shared<taobao>();
	
	std::shared_ptr<iphone> p_ip = std::make_shared<iphone>(p_wz);
	std::shared_ptr<huawei> p_hw = std::make_shared<huawei>(p_tb);
	
    p_ip->opt();
    p_hw->opt();
	
	std::cout << "done .." << std::endl;
    return 0;
}

Operation result: