Main window in QT application

1. Toolbar of the main window in the application
The main window is with the user Top level window for long-term interaction
programmatic most Functions are directly provided by the main window
The main window is usually The first window displayed after the application starts
The whole program consists of a main window and Multiple dialog boxes form
Qt The main window in ：
Qt The concept of main window is directly supported in the development platform
QMainWindow yes Qt The base class of the main window in
QMainWindow Inherited from QWidget Is a container type component
QMainWindow The secret encapsulated in ：
QMainWindow Component layout in ：
stay Qt Provides menu related class components ：
stay Qt Create a menu in the main window ：

QMenubar* mb = menuBar();  //member function
QMenu* menu = new QMenu("File(&F)");
QAction* action = new QAction("New", NULL);

menu->addAction(action);
mb->addMenu(menu);

Shortcut key settings ：

action->setShortcut(QKeySequence(KEY));

QKeySeauence - Qt Classes related to shortcut keys in 
KEY - QT Constants representing key values in 

2. Status bar in main window