I know where the problem is, but i have no idea how to fix it. The problem is located in websubwindow.cpp: when it tries to access the child widgets it segfaults, starting at the first vbox->addWidget().

The file structure is:
torah.cpp
torah.h
gui/websubwindow.cpp
gui/websubwindow.h

websubwindow.cpp
Qt Code: 
  1. #include "websubwindow.h"
  2.  
  3. webSubWindow::webSubWindow(QWidget * parent, Qt::WindowFlags flags)
  4. 	: QMdiSubWindow(parent, flags)
  5. 	{
  6. 		setWindowTitle(tr("Personal"));
  7. 		setAttribute(Qt::WA_DeleteOnClose);
  8.  
  9. 		vbox->addWidget(addressLine);
  10. 		vbox->addWidget(progressBar);
  11. 		vbox->addWidget(webView);
  12. 		vbox->addWidget(statusBar);
  13.  
  14. 		centralWidget->setLayout(vbox);
  15.  
  16. 		progressBar->setHidden(true);
  17.  
  18. 		addressLine->setEditText("http://");
  19.  
  20. 		setWidget(centralWidget);
  21.  
  22. 		connect(addressLine, SIGNAL(activated(const QString &)), this, SLOT(goToUrl(const QString &)));
  23. 		//connect(addressLine->lineEdit(), SIGNAL(returnPressed()), this, SLOT(goToUrl()));
  24. 	}
  25.  
  26. webSubWindow::~webSubWindow()
  27. 	{
  28. 		delete centralWidget;
  29. 		delete vbox;
  30. 		delete addressLine;
  31. 		delete progressBar;
  32. 		delete webView;
  33. 		delete url;
  34. 	}
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websubwindow.h
Qt Code: 
  1. #ifndef WEBSUBWINDOW_H
  2. #define WEBSUBWINDOW_H
  3.  
  4. #include <QtGui/QMdiSubWindow>
  5. #include <QtGui/QWidget>
  6. #include <QtGui/QVBoxLayout>
  7. #include <QtGui/QComboBox>
  8. #include <QtGui/QProgressBar>
  9. #include <QtGui/QStatusBar>
  10.  
  11. #include <QtCore/QUrl>
  12.  
  13. #include <QtWebKit/QWebView>
  14.  
  15. class webSubWindow : public QMdiSubWindow
  16. 	{
  17. 		Q_OBJECT
  18.  
  19. 		private:
  20. 			QWidget *centralWidget;
  21. 			QVBoxLayout *vbox;
  22. 			QUrl *url;
  23.  
  24. 		public:
  25. 			webSubWindow(QWidget * parent = 0, Qt::WindowFlags flags = 0);
  26. 			~webSubWindow();
  27. 			QComboBox *addressLine;
  28. 			QProgressBar *progressBar;
  29. 			QWebView *webView;
  30. 			QStatusBar *statusBar;
  31.  
  32. 		private slots:
  33. 			void goToUrl(const QString &url);
  34. 	};
  35.  
  36. #endif // WEBSUBWINDOW_H
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torah.cpp
Qt Code: 
  1. #include "torah.h"
  2. #include "ui_torah.h"
  3. #include "gui/websubwindow.h"
  4.  
  5. Torah::Torah(QWidget *parent)
  6. 	: QMainWindow(parent), ui(new Ui::TorahClass)
  7. 	{
  8. 		ui->setupUi(this);
  9.  
  10. 		ui->action_Refresh->setVisible(false);
  11. 		ui->action_Stop->setVisible(false);
  12. 		ui->action_Back->setEnabled(false);
  13. 		ui->action_Forward->setEnabled(false);
  14.  
  15. 		connect(ui->actionNew_Tab, SIGNAL(triggered()), this, SLOT(addTab()));
  16. 	}
  17.  
  18. Torah::~Torah()
  19. 	{
  20. 		delete ui;
  21. 	}
  22.  
  23. void Torah::addTab()
  24. 	{
  25. 		webSubWindow *child = new webSubWindow;
  26. 		//QMdiSubWindow *child = new QMdiSubWindow;
  27. 		ui->mdiArea->addSubWindow(child);
  28. 		child->show();
  29. 	}
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torah.h
Qt Code: 
  1. #ifndef TORAH_H
  2. #define TORAH_H
  3.  
  4. #include <QtGui/QMainWindow>
  5.  
  6. namespace Ui
  7. {
  8. 	class TorahClass;
  9. }
  10.  
  11. class Torah : public QMainWindow
  12. 	{
  13. 		Q_OBJECT
  14.  
  15. 		public:
  16. 			Torah(QWidget *parent = 0);
  17. 			~Torah();
  18.  
  19. 		private:
  20. 			Ui::TorahClass *ui;
  21.  
  22. 		private slots:
  23. 			void addTab();
  24. 	};
  25.  
  26. #endif // TORAH_H
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Any help is appreciated; i've been trying many things to try and solve the problem, but i'm getting no where.