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/*! 

    \page qaxserver-demo-hierarchy.html

    \title Qt Widget Hierarchy

    \input examples/activeqt/hierarchy-demo.qdocinc

*/

/*!

    \example activeqt/hierarchy

    \title Hierarchy Example (ActiveQt)

    The Hierarchy example is shows how to write an in-process ActiveX

    control. The control is a QWidget subclass with child widgets

    that are accessible as sub-types.

    \snippet examples/activeqt/hierarchy/objects.h 0

    The \c QParentWidget class provides slots to create a widget

    with a name, and to return a pointer to a named widget. The class

    declaration uses \c Q_CLASSINFO() to provide the COM identifiers for

    this class.

    \snippet examples/activeqt/hierarchy/objects.cpp 0

    The constructor of QParentWidget creates a vertical box layout.

    New child widgets are automatically added to the layout.

    \snippet examples/activeqt/hierarchy/objects.cpp 1

    The \c createSubWidget slot creates a new \c QSubWidget with

    the name provided in the parameter, and sets the label to that

    name. The widget is also shown explicitly.

    \snippet examples/activeqt/hierarchy/objects.cpp 2

    The \c subWidget slot uses the \c QObject::child() function and

    returns the first child of type \c QSubWidget that has the requested

    name.

     \snippet examples/activeqt/hierarchy/objects.h 1

    The \c QSubWidget class has a single string-property \c label,

    and implements the paintEvent to draw the label. The class uses

    again \c Q_CLASSINFO to provide the COM identifiers, and also sets

    the \e ToSuperClass attribute to \e QSubWidget, to ensure that only

    no slots of any superclasses (i.e. QWidget) are exposed.

    \snippet examples/activeqt/hierarchy/objects.cpp 3

    \snippet examples/activeqt/hierarchy/objects.cpp 4

    The implementation of the QSubWidget class is self-explanatory.

    \snippet examples/activeqt/hierarchy/main.cpp 0

    The classes are then exported using a QAxFactory. \c QParentWidget is

    exported as a full class (which can be created ), while \c QSubWidget is

    only exported as a type, which can only be created indirectly through

    APIs of \c QParentWidget.

    To build the example you must first build the QAxServer library.

    Then run qmake and your make tool in \c examples/activeqt/hierarchy.

    The \l{qaxserver-demo-hierarchy.html}{demonstration} requires

    your WebBrowser to support ActiveX controls, and scripting to be

    enabled.

    \snippet examples/activeqt/hierarchy-demo.qdocinc 0

*/