source: trunk/doc/src/windows-and-dialogs/mainwindow.qdoc@ 569

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/*!
    \group mainwindow-classes
    \title Main Window and Related Classes
*/

/*!
    \page application-windows.html
    \title Application Windows and Dialogs
    \ingroup frameworks-technologies

    \nextpage The Application Main Window

    A \l{Widgets}{widget} that is not embedded in a parent widget is called a window.
    Usually, windows have a frame and a title bar, although it is also possible to create
    windows without such decoration using suitable window flags). In Qt, QMainWindow
    and the various subclasses of QDialog are the most common window types.

    In applications, windows provide the screen space upon which the user
    interface is built. Windows separate applications visually from each other
    and usually provide a window decoration that allows the user to resize and
    position the applications according to his preferences. Windows are typically
    integrated into the desktop environment and to some degree managed by the
    window management system that the desktop environment provides. For instance,
    selected windows of an application are represented in the task bar.

    \section1 Primary and Secondary Windows

    Any QWidget that has no parent will become a window, and will on most platforms
    be listed in the desktop's task bar. This is usually only wanted for one
    window in the application, the \e{primary window}.

    In addition, a QWidget that has a parent can become a window by setting the 
    \l{Qt::WindowType}{Qt::WA_Window} flag. Depending on the window management system
    such \e{secondary windows} are usually stacked on top of their respective parent
    window, and not have a task bar entry of their own.

    The QMainWindow and the QDialog classes set the Qt::WA_Window flag in their
    constructor, as they are designed to be used as windows and provide facilities
    that are not wanted for child widgets.