shiboken绑定C++供python使用

C++类函数封装给python调用，大致分为三个部分，第一部分是把我们的C++类函数等封装成一个dll,即动态库。第二部分是生成一个绑定代码，就是用shiboken2根据我们需要封装暴露的文件，生成pythonC++代码。然后第三部分，就是根据第一和第二部分生成的库和代码，进一步封装成py库。然后python文件直接可以调用该库。具体代码如下，源码用的是python的官方源码。主要讲解每个部分的使用。

源码：
------------------icecream.cpp------------------------------------
#include "icecream.h"

Icecream::Icecream(const std::string &flavor) : m_flavor(flavor) {}

Icecream::~Icecream() {}

const std::string Icecream::getFlavor()
{
    return m_flavor;
}

Icecream *Icecream::clone()
{
    return new Icecream(*this);
}
-------------------------------------------icecream.h------------------------------------------------------

#ifndef ICECREAM_H
#define ICECREAM_H

#include <string>

#include "macros.h"

class BINDINGS_API Icecream
{
public:
    Icecream(const std::string &flavor);
    virtual Icecream *clone();
    virtual ~Icecream();
    virtual const std::string getFlavor();

private:
    std::string m_flavor;
};

#endif // ICECREAM_H
--------------------------------------------truck.cpp------------------------------------------------------

#include <iostream>
#include <random>

#include "truck.h"

Truck::Truck(bool leaveOnDestruction) : m_leaveOnDestruction(leaveOnDestruction) {}

Truck::Truck(const Truck &other)
{
    for (size_t i = 0; i < other.m_flavors.size(); ++i) {
        addIcecreamFlavor(other.m_flavors[i]->clone());
    }
}

Truck &Truck::operator=(const Truck &other)
{
    if (this != &other) {
        clearFlavors();
        for (size_t i = 0; i < other.m_flavors.size(); ++i) {
            addIcecreamFlavor(other.m_flavors[i]->clone());
        }
    }
    return *this;
}

Truck::~Truck()
{
    if (m_leaveOnDestruction)
        leave();
    clearFlavors();
}

void Truck::addIcecreamFlavor(Icecream *icecream)
{
    m_flavors.push_back(icecream);
}

void Truck::printAvailableFlavors() const
{
    std::cout << "It sells the following flavors: \n";
    for (size_t i = 0; i < m_flavors.size(); ++ i) {
        std::cout << "  * "  << m_flavors[i]->getFlavor() << '\n';
    }
    std::cout << '\n';
}

void Truck::arrive() const
{
    std::cout << m_arrivalMessage;
}

void Truck::leave() const
{
    std::cout << "The truck left the neighborhood.\n";
}

void Truck::setLeaveOnDestruction(bool value)
{
    m_leaveOnDestruction = value;
}

void Truck::setArrivalMessage(const std::string &message)
{
    m_arrivalMessage = message;
}

bool Truck::deliver() const
{
    std::random_device rd;
    std::mt19937 mt(rd());
    std::uniform_int_distribution<int> dist(1, 2);

    std::cout << "The truck started delivering icecream to all the kids in the neighborhood.\n";
    bool result = false;

    if (dist(mt) == 2)
        result = true;

    return result;
}

void Truck::clearFlavors()
{
    for (size_t i = 0; i < m_flavors.size(); ++i) {
        delete m_flavors[i];
    }
    m_flavors.clear();
}

----------------------------------------------truck.h----------------------------------------------------
#ifndef TRUCK_H
#define TRUCK_H

#include <vector>

#include "icecream.h"
#include "macros.h"

class BINDINGS_API Truck {
public:
    Truck(bool leaveOnDestruction = false);
    Truck(const Truck &other);
    Truck& operator=(const Truck &other);
    ~Truck();

    void addIcecreamFlavor(Icecream *icecream);
    void printAvailableFlavors() const;

    bool deliver() const;
    void arrive() const;
    void leave() const;

    void setLeaveOnDestruction(bool value);
    void setArrivalMessage(const std::string &message);

private:
    void clearFlavors();

    bool m_leaveOnDestruction = false;
    std::string m_arrivalMessage = "A new icecream truck has arrived!\n";
    std::vector<Icecream *> m_flavors;
};

#endif // TRUCK_H
------------------------------------------bindings.h-----------------------------------------------------

#ifndef BINDINGS_H
#define BINDINGS_H

#include "icecream.h"
#include "truck.h"

#endif // BINDINGS_H
------------------------------------------------macros.h------------------------------------------------

#ifndef MACROS_H
#define MACROS_H

#if defined _WIN32 || defined __CYGWIN__
    // Export symbols when creating .dll and .lib, and import them when using .lib.
    #if BINDINGS_BUILD
        #define BINDINGS_API __declspec(dllexport)
    #else
        #define BINDINGS_API __declspec(dllimport)
    #endif
    // Disable warnings about exporting STL types being a bad idea. Don't use this in production
    // code.
    #pragma warning( disable : 4251 )
#else
    #define BINDINGS_API
#endif

#endif // MACROS_H
------------------------------------------bindings.xml------------------------------------------------
<?xml version="1.0"?&g