组合和继承
继承是白箱复用(whiter-box-reuse),获得继承类的内部细节
组合是黑盒测试(black-box-reuse),无法得走类的内部实现
class C
{//
};
//组合
class E
{
private:C _cc;
};
is-a 关系用继承,人-学生;has-a 关系用组合 车-轮胎。
多态&#…
官网参考链接:https://developer.android.google.cn/develop/ui/views/appwidgets/overview
1、什么是小部件
App widgets are miniature application views that can be embedded in other applications (such as the home screen) and receive periodic updates…