setMenuBar(menuBar );

QToolBar *toolBar = new QToolBar(this);

addToolBar(Qt::TopToolBarArea, toolBar); 

QStatusBar

QStatusBar *stBar = statusBar(); 

setStatusBar(stBar);

QDockWidget *dockWidget = new QDockWidget("dock window",this);

 addDockWidget(Qt::BottomDockWidgetArea, dockWidget);

QTextEdit *textEdit = new QTextEdit(this);

setCentralWidget(textEdit);