单例模式 & 组合模式

#include <list>
#include <string>
#include <algorithm>

using namespace std;

class Component {
public:
    virtual void process() = 0;
    virtual ~Component(){}
};

// tree node
class Composite : public Component {
private:
    string name;
    list<Component*> elements;
public:
    Composite(const string& s) : name(s) {}
    void add(Component* element) {
        this->elements.push_back(element);
    }
    void  remove(Component* element) {
        this->elements.remove(element);
    }
    void process() {
        cout << (this->name) << endl;
        for (auto& e : elements) {
            e->process();
        }
    }
};

// leaf node
class Leaf : public Component {
private:
    string name;
public:
    Leaf(string s) : name(s) {}
    void process() {
        cout << this->name << endl;
    }
};

int main() {
    Composite root("WinForm(WINDOW窗口)");
    Composite frame("Frame(FRAME1)");

    Leaf login("Button(登录)");
    Leaf reg("Button(注册)");
    Leaf logo("Picture(LOGO图片)");
    Leaf user("Label(用户名)");
    Leaf userTextBox("TextBox(文本框)");
    Leaf passwd("Label(密码)");
    Leaf passwdBox("PasswdBox(密码框)");
    Leaf checkBox("CheckBox(复选框)");
    Leaf textBox("TextBox(记住用户名)");
    Leaf linkLabel("LinkLabel(忘记密码)");
    root.add(&logo);
    root.add(&frame);
    root.add(&login);
    root.add(&reg);
    frame.add(&user);
    frame.add(&userTextBox);
    frame.add(&passwd);
    frame.add(&passwdBox);
    frame.add(&checkBox);
    frame.add(&textBox);
    frame.add(&linkLabel);

    root.process();
}