C++设计模式之组合模式(Composite)

#include <iostream>
#include <list>
#include <string>
using namespace std;
class menu
{
public:
  menu(string in) : name(in){}
  ~menu(){}
  virtual void Add(menu*) = 0;
  virtual void Remove(menu*) = 0;
  virtual void showname() = 0;
protected:
  string name;
};

class Leafmenu : public menu
{
public:
  Leafmenu(string in) : menu(in){}
  ~Leafmenu(){}
  void showname()
  {
    cout<< "Leaf : " << name << endl;
  }
  virtual void Add(menu*){}
  virtual void Remove(menu*){}
};

class Compositemenu : public menu
{
public:
  Compositemenu(string in) : menu(in){}
  void showname()
  {
    cout<< "Composit : "<< name << endl;
    list<menu*>::iterator iter = m_child.begin();
    while (iter != m_child.end())
    {
      (*iter)->showname();
      iter++;
    }
  }
  virtual void Add(menu*m){ m_child.push_back(m); }
  virtual void Remove(menu*m){ m_child.remove(m); }
private:
  list<menu*> m_child;
};
//调用实现
int main
{
  Compositemenu mainmenu("Main");

  /***添加File菜单****/
  Compositemenu *pFile = new Compositemenu("File");
  Leafmenu *pNew = new Leafmenu("New");
  Leafmenu *pOpen = new Leafmenu("Open");
  Leafmenu *pClose = new Leafmenu("Close");
  pFile->Add(pNew);
  pFile->Add(pOpen);
  pFile->Add(pClose);
  mainmenu.Add(pFile);

  /***添加Edit菜单****/
  Compositemenu *pEdit = new Compositemenu("Edit");
  Leafmenu *pCopy = new Leafmenu("Copy");
  Leafmenu *pPaste = new Leafmenu("Paste");
  pEdit->Add(pCopy);
  pEdit->Add(pPaste);
  mainmenu.Add(pFile);

  Leafmenu *pExit = new Leafmenu("Exit");
  Leafmenu *pHelp = new Leafmenu("Help");
  mainmenu.Add(pExit);
  mainmenu.Add(pHelp);

  mainmenu.showname();

  delete pNew;
  delete pOpen;
  delete pClose;
  delete pFile;
  delete pCopy;
  delete pPaste;
  delete pEdit;
  delete pExit;
  delete pHelp;
}