Hi,

I'm new to using Qt and I'm having a small problem, when I try to execute my program I'm getting this error message

Unhandled exception at 0x671e26f1 (QtCored4.dll) in practice.exe: 0xC0000005: Access violation reading location 0x00000004.

and it's telling me it is in qobject.cpp (which obviously can't be right).

Qt Code: 
  1. #include <QtGui> 
  2. #include "practice.h"
  3.  
  4. practice::practice(QWidget *parent, Qt::WFlags flags)
  5. 	: QMainWindow(parent, flags)
  6. {
  7. 	ui.setupUi(this);
  8. 	connect(pushButton, SIGNAL(clicked()), this, SLOT(addItem())); 
  9. 	connect(pushButton_2, SIGNAL(clicked()), this, SLOT(removeItem()));
  10. 	connect(pushButton_3, SIGNAL(clicked()), this, SLOT(quit()));
  11. }
  12. void practice::addItem()
  13. {
  14.     if( lineEdit->text().length() > 0 )
  15.     {
  16. 	listWidget->insertItem(1, lineEdit->text() );
  17. 	lineEdit->clear();
  18.     }
  19.  
  20.     lineEdit->setFocus();
  21. }
  22.  
  23. void practice::removeItem()
  24. {
  25. 	delete listWidget->takeItem(1);
  26. }
  27.  
  28.  
  29. void practice::init()
  30. {
  31.     listWidget->clear();
  32.     lineEdit->setFocus();
  33. }
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Any ideas from anyone? Also while I'm here, can anyone explain to me the correct way to access mimeData()? I was hoping to do a check for an empty list widget with it and then only if the list wasn't empty could you perform the remove, but I can't quite figure out the syntax. Thanks.