#include <QtGui>
#if QT_VERSION >= 0x50000
#include <QtWidgets>
#endif

class MainWindow : public QMainWindow
{
public:
  MainWindow()
  {
    setCentralWidget(new QTextEdit(this));
    QDockWidget *dock1 = new QDockWidget(this);
    dock1->setObjectName("dock");
    dock1->setWidget(new QLabel("Label 1", dock1));
    addDockWidget(Qt::LeftDockWidgetArea, dock1);
    readSettings();
  }
  void readSettings() {
    QSettings settings("SomeTest", "DockWidgetTest");
    restoreGeometry(settings.value("geometry").toByteArray());
    restoreState(settings.value("windowState").toByteArray());
  }

  void writeSettings()
  {
    QSettings settings("SomeTest", "DockWidgetTest");
    settings.setValue("geometry", saveGeometry());
    settings.setValue("windowState", saveState());
  }

  void closeEvent(QCloseEvent *event)
  {
    QMainWindow::closeEvent(event);
    writeSettings();
  }
};

int main(int argc, char *argv[])
{
  QApplication app(argc, argv);
  MainWindow window;
  window.show();
  return app.exec();
}