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/*!
  \page widgets-and-layouts.html
  \title Widgets and Layouts
  \ingroup qt-gui-concepts
  \brief The primary elements for designing user interfaces in Qt.

  \section1 Widgets

  Widgets are the primary elements for creating user interfaces in Qt.
  \l{The Widget Classes}{Widgets} can display data and status information,
  receive user input, and provide a container for other widgets that
  should be grouped together. A widget that is not embedded in a
  parent widget is called a \l{Window and Dialog Widgets} {window}.

  \image parent-child-widgets.png A parent widget containing various child widgets.

  The QWidget class provides the basic capability to render to the
  screen, and to handle user input events. All UI elements that Qt
  provides are either subclasses of QWidget, or are used in connection
  with a QWidget subclass. Creating custom widgets is done by
  subclassing QWidget or a suitable subclass and reimplementing the
  virtual event handlers.

  \section1 Layouts

  \l{Layout Management}{Layouts} are an elegant and flexible way to
  automatically arrange child widgets within their container. Each
  widget reports its size requirements to the layout through the
  \l{QWidget::}{sizeHint} and \l{QWidget::}{sizePolicy} properties,
  and the layout distributes the available space accordingly.

  \table
  \row    
  \o \image qgridlayout-with-5-children.png
  \o \image qformlayout-with-6-children.png
  \endtable

  \l{Qt Designer Manual}{\QD} is a powerful tool for interactively creating and
  arranging widgets in layouts.

  \section1 Widget Styles

  \l{Styles &amp Style Aware Widgets}{Styles} draw on behalf of
  widgets and encapsulate the look and feel of a GUI. Qt's built-in
  widgets use the QStyle class to perform nearly all of their drawing,
  ensuring that they look exactly like the equivalent native widgets.
    
  \table
  \row
  \o \image windowsxp-tabwidget.png
  \o \image plastique-tabwidget.png
  \o \image macintosh-tabwidget.png
  \endtable

  \l{Qt Style Sheets} are a powerful mechanism that allows you to customize the
  appearance of widgets, in addition to what is already possible by subclassing QStyle.

  \section1 The Widget Classes

  The following sections list the widget classes. See the \l{Qt Widget
  Gallery} for some examples.

  \section2 Basic Widgets

  These basic widgets (controls), e.g. buttons, comboboxes and
  scroll bars, are designed for direct use.

  \table
  \row
  \o \image windows-label.png
  \o \image windowsvista-pushbutton.png
  \o \image gtk-progressbar.png
  \row
  \o \image plastique-combobox.png
  \o \image macintosh-radiobutton.png
  \o \image cde-lineedit.png
  \endtable

  \annotatedlist basicwidgets

  \section2 Advanced Widgets

  Advanced GUI widgets, e.g. tab widgets and progress bars, provide
  more complex user interface controls.

  \table
  \row
  \o \image windowsxp-treeview.png
  \o \image gtk-calendarwidget.png
  \o \image qundoview.png
  \endtable

  \annotatedlist advanced

  \table
  \row
  \o \image windowsvista-tabwidget.png 
  \o \image macintosh-groupbox.png
  \endtable

  \section2 Organizer Widgets

  Classes like splitters, tab bars, button groups, etc are used for
  organizing and grouping GUI primitives into more complex
  applications and dialogs.

  \annotatedlist organizers

  \section2 Abstract Widget Classes

  The abstract widget classes are base classes. They are not usable as
  standalone classes but provide functionality when they are subclassed.

  \annotatedlist abstractwidgets
*/

/*!
    \group advanced
    \title Advanced Widgets
*/

/*!
    \group abstractwidgets
    \title Abstract Widget Classes
*/

/*!
    \group basicwidgets
    \title Basic Widgets
*/

/*!
    \group organizers
    \title Organizers
*/