1 #ifndef CDUCK_H
 2 #define CDUCK_H
 3 class CInterface_fly;
 4 class CInterface_quak;
 5
 6 class CDuck
 7 {
 8 public:
 9     CDuck();
10     virtual ~CDuck();
11
12 public:
13   virtual void performFly();
14   virtual void performQuak();
15 public:
16     virtual void setFlyBehavior(CInterface_fly* pInterfaceFly);
17     virtual void setQuackBehavior(CInterface_quak* pInterfaceQuak);
18
19 protected:
20    CInterface_fly* m_pInterface_fly;
21    CInterface_quak* m_pInterface_quak;
22
23 };
24
25 #endif // CDUCK_H

 1 #include "duck.h"
 2 #include <interface_fly.h>
 3 #include <interface_quak.h>
 4 #include <QDebug>
 5 CDuck::CDuck()
 6 {
 7
 8 }
 9  CDuck::~CDuck()
10 {
11
12 }
13 void CDuck::setFlyBehavior(CInterface_fly* pInterfaceFly)
14 {
15    m_pInterface_fly = pInterfaceFly;
16 }
17 void CDuck::setQuackBehavior(CInterface_quak* pInterfaceQuak)
18 {
19     m_pInterface_quak = pInterfaceQuak;
20 }
21 void CDuck::performFly()
22 {
23     if(m_pInterface_fly)
24     {
25          m_pInterface_fly->fly();
26     }
27 }
28 void CDuck::performQuak()
29 {
30     if(m_pInterface_quak)
31     {
32          m_pInterface_quak->quak();
33     }
34 }

 1 #include <QCoreApplication>
 2 #include <redheadduck.h>
 3 #include <duck.h>
 4 #include "interface_fly.h"
 5 #include "interface_quak.h"
 6 #include "flywithwings.h"
 7 #include "squeak.h"
 8 int main(int argc, char *argv[])
 9 {
10     QCoreApplication a(argc, argv);
11    CInterface_fly* pInterface_fly = new FlyWithWings();
12    CInterface_quak* pInterface_quak = new Squeak();
13     CDuck* pDuck = new RedHeadDuck();
14     pDuck->setFlyBehavior(pInterface_fly);
15     pDuck->setQuackBehavior(pInterface_quak);
16     pDuck->performFly();
17     pDuck->performQuak();
18       return a.exec();
19 }