Hi guys,
Seems to be silly question but I'm unable to achieve it.

I'm porting my application from Qt3 to Qt4 and is using Qt3 support classes for a while. The problem is I use Q3MainWindows, Q3DockWindow, QSplitter, Q3Frame as shown in code below. Now I want to hide/unhide the dockWindow. I do this by right clicking on toolBar. First I right click and the dockWindow is hidden then again I rightClick and click on 'routes' but the dockWindow doesnt appear. I dont know why.

Please dont suggest me to use QMainWindow, QDockWidget or so... I have already made lots of changes and cant revert back. Please help me to rectify this problem with the solution given
Qt Code: 
  1. #include <Q3MainWindow>
  2. #include <QSplitter>
  3.  
  4. class MainWindow : public Q3MainWindow
  5. {
  6. 	Q_OBJECT
  7.  
  8. public:
  9. 	MainWindow(QWidget *parent = 0);
  10. 	~MainWindow();
  11.  
  12. private:
  13. 	Q3DockWindow	*treeDock;
  14. 	QSplitter	*s2;
  15. 	Q3Frame		*frame;
  16.  
  17. };
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Qt Code: 
  1. MainWindow::MainWindow(QWidget *parent)
  2. 	: Q3MainWindow(parent)
  3. {
  4. 	treeDock = new Q3DockWindow( this, "routes" );
  5. 	Q_CHECK_PTR( treeDock );
  6. 	moveDockWindow( treeDock, Qt::Left );
  7. 	treeDock->setHorizontallyStretchable( true );
  8. 	treeDock->setVerticallyStretchable( true );
  9. 	treeDock->setResizeEnabled( true );
  10. 	treeDock->setOrientation( Qt::Vertical );
  11. 	treeDock->setCaption( tr("Routes") );	
  12.  
  13. 	s2 = new QSplitter( Qt::Vertical, this, "splitter" );
  14. 	Q_CHECK_PTR( s2 );
  15. 	setCentralWidget( s2 );
  16. 	frame = new Q3Frame( s2 );
  17. 	frame->setBackgroundColor( Qt::white );
  18. 	frame->setAutoFillBackground( true );
  19.  
  20. 	Q3PopupMenu	*file = new Q3PopupMenu;
  21. 	Q_CHECK_PTR( file );
  22.  
  23. 	int openId = file->insertItem(  tr("&Open..."), this, SLOT(fileOpen()), 
  24. 		Qt::CTRL+Qt::Key_O );
  25.  
  26. 	Q3PopupMenu	*edit = new Q3PopupMenu;
  27. 	Q_CHECK_PTR( edit );
  28. 	int copyId = edit->insertItem(  tr("&Copy"), this, SLOT(copy()), Qt::CTRL+Qt::Key_C );	
  29.  
  30. 	menuBar()->insertItem( tr("&File"), file );
  31. 	menuBar()->insertItem( tr("&Edit"), edit );
  32. }
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Qt Code: 
  1. #include <QtGui/QApplication>
  2. #include "mainwindow.h"
  3.  
  4. int main(int argc, char *argv[])
  5. {
  6. 	QApplication a(argc, argv);
  7. 	MainWindow w;
  8. 	w.show();
  9. 	a.connect(&a, SIGNAL(lastWindowClosed()), &a, SLOT(quit()));
  10. 	return a.exec();
  11. }
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Thanks in advance