addEventHandler有什么特殊的地方吗?

zhuliangxiong

我写了一个EventHanlder来选中节点 结果addEventHandler后 没有任何效果呢.是不是有什么特殊的地方要处理啊.
头文件:

1. /*
   
2. * QNodePickHandler.h
   
3. *
   
4. *  Created on: Mar 21, 2009
   
5. *      Author: Administrator
   
6. */
   
7. 
   
8. #ifndef QNODEPICKHANDLER_H_
   
9. #define QNODEPICKHANDLER_H_
   
10. #include <osgViewer/Viewer>
    
11. #include <osgViewer/View>
    
12. #include <osg/Node>
    
13. #include <osg/Geode>
    
14. #include <osg/Group>
    
15. #include <osgDB/ReadFile>
    
16. #include <osgDB/WriteFile>
    
17. #include <osgFX/Scribe>
    
18. #include <osgGA/GUIEventHandler>
    
19. 
    
20. using namespace osg;
    
21. using namespace osgGA;
    
22. using namespace osgFX;
    
23. using namespace osgViewer;
    
24. class QNodePickHandler:public GUIEventHandler
    
25. {
    
26. public:
    
27.         QNodePickHandler();
    
28.         virtual ~QNodePickHandler();
    
29.         osgViewer::View* getViewer() const;
    
30.         void setViewer(osgViewer::View* viewer);
    
31.         bool handle(const GUIEventAdapter& ea,const GUIActionAdapter& aa);
    
32.         void enable(bool enable);
    
33.         bool isEnable() const;
    
34. private:
    
35.         void pick(float x,float y);
    
36. private:
    
37.   bool _enabled;
    
38.         float _x;
    
39.         float _y;
    
40.         osgViewer::View* _viewer;
    
41. };
    
42. 
    
43. #endif /* QNODEPICKHANDLER_H_ */

复制代码

实现:

1. /*
   
2. * QNodePickHandler.cpp
   
3. *
   
4. *  Created on: Mar 21, 2009
   
5. *      Author: Administrator
   
6. */
   
7. 
   
8. #include "QNodePickHandler.h"
   
9. 
   
10. QNodePickHandler::QNodePickHandler()
    
11. {
    
12.   _x = 0.0f;
    
13.   _y = 0.0f;
    
14.   _enabled = true;
    
15. }
    
16. 
    
17. QNodePickHandler::~QNodePickHandler()
    
18. {
    
19.   // TODO Auto-generated destructor stub
    
20. }
    
21. osgViewer::View* QNodePickHandler::getViewer() const
    
22. {
    
23.   return _viewer;
    
24. }
    
25. void QNodePickHandler::setViewer(osgViewer::View* viewer)
    
26. {
    
27.   _viewer = viewer;
    
28. }
    
29. bool QNodePickHandler::handle(const GUIEventAdapter& ea,
    
30.     const GUIActionAdapter&aa)
    
31. {
    
32.   if (!_viewer||!_enabled)
    
33.     return false;
    
34.   switch (ea.getEventType())
    
35.   {
    
36.     case GUIEventAdapter::PUSH: {
    
37.       _x = ea.getX();
    
38.       _y = ea.getY();
    
39.       break;
    
40.     }
    
41.     case GUIEventAdapter::RELEASE: {
    
42.       if (_x == ea.getX() && _y == ea.getY()) {
    
43.         pick(_x, _y);
    
44.       }
    
45.       break;
    
46.     }
    
47.     default:
    
48.       break;
    
49.   }
    
50.   return false;
    
51. }
    
52. void QNodePickHandler::pick(float x, float y)
    
53. {
    
54.   Node* node = NULL;
    
55.   Group* parent = new Group();
    
56.   osgUtil::LineSegmentIntersector::Intersections intersections;
    
57.   if (_viewer->computeIntersections(x, y, intersections)) {
    
58.     osgUtil::LineSegmentIntersector::Intersection inter =
    
59.         *intersections.begin();
    
60.     NodePath& nodePath = inter.nodePath;
    
61.     if (nodePath.size() > 0)
    
62.       node = nodePath[nodePath.size() - 1];
    
63.     if (nodePath.size() > 1)
    
64.       parent = dynamic_cast<Group*> (nodePath[nodePath.size() - 2]);
    
65.     if (parent && node) {
    
66.       Scribe* parentAsScribe = dynamic_cast<Scribe*> (parent);
    
67.       if (!parentAsScribe) {
    
68.         Scribe* scribe = new Scribe();
    
69.         scribe->addChild(node);
    
70.         parent->replaceChild(node, scribe);
    
71.       } else {
    
72.         Node::ParentList parentList = parentAsScribe->getParents();
    
73.         for (Node::ParentList::iterator itr = parentList.begin(); itr
    
74.             != parentList.end(); ++itr) {
    
75.           (*itr)->replaceChild(parentAsScribe, node);
    
76.         }
    
77.       }
    
78.     }
    
79.   }
    
80. }
    
81. void QNodePickHandler::enable(bool enable)
    
82. {
    
83. _enabled=enable;
    
84. }
    
85. bool QNodePickHandler::isEnable() const
    
86. {
    
87.   return _enabled;
    
88. }

复制代码

zhuliangxiong

全部代码如下:
src.rar (1.8 KB, 下载次数: 156)

2009-3-21 23:02 上传

点击文件名下载附件

array

您的handle函数为：

1. bool handle(const GUIEventAdapter& ea,const GUIActionAdapter& aa);

复制代码

而GUIEventHandler的handle函数的正确派生格式为：

1. bool handle (const GUIEventAdapter& ea, GUIActionAdapter& aa);

复制代码

因此我认为这里您并没有正确使用虚函数。

zhuliangxiong

老大一出手 就知有没有

liuzhiyu123

高手啊

tianxiao888

细节错误，呵呵