与前面两个工厂不同的是，抽象工厂提供的产品不是同一个类型的东西，而是一系列配套的不同产品。例如一个网站可能会有Light theme和Dark theme，对应不同的皮肤skin，按钮button，搜索栏searchbar。如何在装配时防止出现Light的skin和button但是搭配上了Dark的searchbar，即是抽象工厂要解决的问题

我们定义一个最终产品类叫做page，page里包括了skin,button,searchbar。然后给出Light和Dark分别对这三个组件的实现，设计一个抽象工厂类，实现LightFactory和DarkFactory来装配page并返回指针

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#include <iostream>

class button {
public:
    virtual void info() = 0;
    virtual ~button(){};
};

class skin {
public:
    virtual void info() = 0;
    virtual ~skin(){};
};

class searchbar {
public:
    virtual void info() = 0;
    virtual ~searchbar(){};
};

class LightButton : public button {
public:
    void info() override {
        std::cout << "LightButton" << std::endl;
    }
};

class DarkButton : public button {
public:
    void info() override {
        std::cout << "DarkButton" << std::endl;
    }
};
class Lightskin : public skin {
public:
    void info() override {
        std::cout << "Lightskin" << std::endl;
    }
};

class Darkskin : public skin {
public:
    void info() override {
        std::cout << "Darkskin" << std::endl;
    }
};
class Lightsearchbar : public searchbar {
public:
    void info() override {
        std::cout << "Lightsearchbar" << std::endl;
    }
};

class Darksearchbar : public searchbar {
public:
    void info() override {
        std::cout << "Darksearchbar" << std::endl;
    }
};

class page {
public:
    page(button *b, skin *s, searchbar *sc):
    b(b), s(s), sc(sc) {

    }
    void show() {
        b->info();
        s->info();
        sc->info();
    }

    ~page() {
        delete b;
        delete s;
        delete sc;
    }
private:
    button *b;
    skin *s;
    searchbar *sc;
};

class abstractFactory {
public:
    virtual page* createPage() = 0;
    virtual ~abstractFactory(){};
};

class LightFactory : public abstractFactory {
public:
    page* createPage() override {
        return new page(new LightButton, new Lightskin, new Lightsearchbar);
    }
};

class DarkFactory : public abstractFactory {
public:
    page* createPage() override {
        return new page(new DarkButton, new Darkskin, new Darksearchbar);
    }
};

int main() {
    abstractFactory *abF = new DarkFactory();

    page *p = abF->createPage();

    p->show();

    delete p;
    delete abF;
    return 0;
}