Hello all:

I have defined a new class which inherits from QObject but when I try to invoke the QObject::metaObject() function from an instance of this object I get an access violation exception. Does anyone know why I cannot call the QObject::metaObject() function???

This is the call to the function from the object pointer pendingMsgs which generates the exception:


Qt Code: 
  1. PendingList *pendingMsgs = new PendingList(this, settings->value("GENERAL/CheckTimeoutInterval").toInt());
  2. const QMetaObject *meta = pendingMsgs->metaObject();
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And this is the class that I have defined (PendingList):

Qt Code: 
  1. #include "MM.h"
  2. #include "Message.h"
  3. #include <QTimer>
  4.  
  5. struct PendingMsg
  6. {
  7. 	Message request; //message pending to receive a response
  8. 	CMD cmd; // type of the pending response {ACK or ORD_RESP}
  9. 	int timeout; // Time that can be stored the message before emitting a timeout signal
  10.  
  11. 	PendingMsg(Message m, CMD c, int t)
  12. 	{
  13. 		request = m;
  14. 		cmd = c; 
  15. 		timeout = t;
  16. 	};
  17.  
  18. 	QString display() const
  19. 	{
  20. 		//return "[" + cmdTags[cmd] + " (" + cmdTags[request.getCmd()] + "), " + stateNames[newState] + "]";
  21. 		return "[" + cmdTags[cmd] + " (" + cmdTags[request.getCmd()] + ")]";
  22. 	};
  23. };
  24.  
  25. class PendingList : public QObject
  26. {
  27.  
  28. 	Q_OBJECT
  29.  
  30. public:
  31. 	PendingList(QObject* parent, int time);
  32. 	~PendingList(void);
  33.  
  34. 	bool add(System sys, Message req, CMD cmd, int time);
  35. 	bool remove(System sys, CMD cmd);
  36.  
  37. 	void setCheckTimeInterval(int t) { checkTimeInterval = t;};
  38.  
  39. 	int size() const;
  40. 	void display() const;
  41.  
  42. private:
  43.  
  44. 	int checkTimeInterval;
  45. 	QTimer timer;
  46.  
  47. 	QList<PendingMsg> list[MAX_CLIENTS];
  48.  
  49. 	// finds the position of the command cmd inside list[sys]
  50. 	int match(System sys, CMD cmd) const;
  51.  
  52. 	bool startIfEmpty();
  53. 	bool stopIfEmpty();
  54.  
  55. 	// Reports that the system 'sys' has not sent a message of type 'cmd1' as answer of the message 'req'
  56. 	void emitTimeout(System sys, CMD cmd, Message req);
  57.  
  58. 	void emitMatch(System sys, CMD cmd, Message req);
  59.  
  60. private slots:
  61.  
  62. 	void checkTimeouts();
  63.  
  64. signals:
  65.  
  66. 	void timeout_ack_insp_mis(System);
  67. 	void timeout_ack_pause(System);
  68. 	void timeout_ack_abort(System);
  69. 	void timeout_ack_resume(System);
  70. 	void timeout_ack_mosaic(System);
  71. 	void timeout_ack_weed_map(System);
  72. 	void timeout_ack_tre_mis(System);
  73. 	void timeout_resp_insp_mis(System);
  74. 	void timeout_resp_pause(System);
  75. 	void timeout_resp_abort(System);
  76. 	void timeout_resp_resume(System);
  77. 	void timeout_resp_mosaic(System);
  78. 	void timeout_resp_weed_map(System);
  79. 	void timeout_resp_tre_mis(System);
  80.  
  81. 	void ack_insp_mis(System);
  82. 	void ack_mosaic(System);
  83. 	void ack_weed_map(System);
  84. 	void ack_tre_mis(System);
  85. 	void ack_unit_ctrl(System);
  86. 	void ack_abort(System);
  87. 	void ack_resume(System);
  88. 	void ack_pause(System);
  89. 	void resp_insp_mis(System);
  90. 	void resp_mosaic(System);
  91. 	void resp_weed_map(System);
  92. 	void resp_tre_mis(System);
  93. 	void resp_abort(System);
  94. 	void resp_resume(System);
  95. 	void resp_pause(System);
  96. };
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