用代码和UML图化解设计模式之《装饰模式》
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灯火互联
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 | 这个模式看了两次，因为我有点不太理解，其实到现在也不太理解。 通过写代码，自我理解就是把对象重新装饰了一遍。通过继承同一个基类。而不用添加额外的类了。。。。 上图吧 通过修饰类达到我们想要的效果。修饰类通常初始化了基类。 [cpp] // Decorator.cpp : 定义控制台应用程序的入口点。 //************************************************************************/ /* @filename Decorator.cpp @author wallwind @createtime 2012/10/29 22:42 @function 命令模式 @email */ /************************************************************************/ #include "stdafx.h" #include <iostream> using namespace std; class Widget { public: Widget(){} virtual ~Widget(){} virtual void show()=0; }; class TextField:public Widget { public: TextField(int ix,int iy) :x(ix),y(iy) { } ~TextField(){} void show() { cout<<"x:"<<x<<endl; cout<<"y:"<<y<<endl; } private: int x; int y; }; class Decorator:public Widget { public: Decorator(Widget* widget) :m_widget(widget) {} virtual ~Decorator() { delete m_widget; } void show() { m_widget->show(); cout<<"Decorator:show()"<<endl; } private: Widget* m_widget; }; class BorderDecorator :public Decorator { public: BorderDecorator(Widget* widget) :Decorator(widget) { } void show() { Decorator::show(); cout<<"BorderDecorator:show()"<<endl; } }; class ScrollDecorator :public Decorator { public: ScrollDecorator(Widget* widget) :Decorator(widget) { } void show() { Decorator::show(); cout<<"ScrollDecorator:show()"<<endl; } }; int _tmain(int argc, _TCHAR* argv[]) { Widget* twidget = new TextField(2,3); Widget *sd = new ScrollDecorator(twidget); Widget *br = new BorderDecorator(twidget); sd->show(); br->show(); return 0; } | |
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