#include <QApplication>
#include <QDockWidget>
#include <QMainWindow>
#include <QResizeEvent>
#include <QSettings>
#include <QtDebug>

class DockWidget : public QDockWidget
{
public:
  DockWidget (const QString& title, QWidget* parent)
   : QDockWidget (title, parent) { }

protected:
  void resizeEvent (QResizeEvent* event)
    { qDebug () << windowTitle () << event->size (); }
};

int main (int argc, char **argv)
{
  QApplication app (argc, argv);
  QMainWindow win;

  win.setDockOptions (QMainWindow::AllowTabbedDocks
                      | QMainWindow::AllowNestedDocks
                      | QMainWindow::AnimatedDocks);

  QDockWidget *d1 = new DockWidget ("Window 1", &win);
  QDockWidget *d2 = new DockWidget ("Window 2", &win);
  QDockWidget *d3 = new DockWidget ("Window 3", &win);
  QDockWidget *d4 = new DockWidget ("Window 4", &win);
  QDockWidget *d5 = new DockWidget ("Window 5", &win);
  QDockWidget *d6 = new DockWidget ("Window 6", &win);

  d1->setObjectName ("dock1");
  d2->setObjectName ("dock2");
  d3->setObjectName ("dock3");
  d4->setObjectName ("dock4");
  d5->setObjectName ("dock5");
  d6->setObjectName ("dock6");

  win.setCentralWidget (0);
  win.addDockWidget (Qt::LeftDockWidgetArea, d1);
  win.addDockWidget (Qt::LeftDockWidgetArea, d2, Qt::Vertical);
  win.addDockWidget (Qt::LeftDockWidgetArea, d3, Qt::Horizontal);
  win.tabifyDockWidget (d3, d4);
  win.tabifyDockWidget (d3, d5);
  win.addDockWidget (Qt::LeftDockWidgetArea, d6, Qt::Horizontal);

  QSettings settings ("testdock.ini", QSettings::IniFormat);

  if (settings.contains ("geometry"))
    win.restoreGeometry (settings.value ("geometry").toByteArray ());
  else
    win.resize (600, 500);
  if (settings.contains ("windowState"))
    win.restoreState (settings.value ("windowState").toByteArray ());

  win.show ();

  app.exec ();

  settings.setValue ("geometry", win.saveGeometry ());
  settings.setValue ("windowState", win.saveState ());
}