/////////////////////////////////////////////////////////////////////////////
-// Name: runtimeclass
+// Name: runtimeclass.h
// Purpose: topic overview
// Author: wxWidgets team
// RCS-ID: $Id$
// Licence: wxWindows license
/////////////////////////////////////////////////////////////////////////////
-/*!
-
- @page runtimeclass_overview Runtime class information (aka RTTI) overview
-
- Classes: #wxObject, #wxClassInfo.
- One of the failings of C++ used to be that no run-time information was provided
- about a class and its position in the inheritance hierarchy.
- Another, which still persists, is that instances of a class cannot be created
- just by knowing the name of a class, which makes facilities such as persistent
- storage hard to implement.
- Most C++ GUI frameworks overcome these limitations by means of a set of
- macros and functions and wxWidgets is no exception. As it originated before the
- addition of RTTI to the C++ standard and as support for it is still missing from
- some (albeit old) compilers, wxWidgets doesn't (yet) use it, but provides its
- own macro-based RTTI system.
- In the future, the standard C++ RTTI will be used though and you're encouraged
- to use whenever possible the #wxDynamicCast() macro which,
- for the implementations that support it, is defined just as dynamic_cast and
- uses wxWidgets RTTI for all the others. This macro is limited to wxWidgets
- classes only and only works with pointers (unlike the real dynamic_cast which
- also accepts references).
- Each class that you wish to be known to the type system should have
- a macro such as DECLARE_DYNAMIC_CLASS just inside the class declaration.
- The macro IMPLEMENT_DYNAMIC_CLASS should be in the implementation file.
- Note that these are entirely optional; use them if you wish to check object
- types, or create instances of classes using the class name. However,
- it is good to get into the habit of adding these macros for all classes.
- Variations on these #macros are used for multiple inheritance, and abstract
- classes that cannot be instantiated dynamically or otherwise.
- DECLARE_DYNAMIC_CLASS inserts a static wxClassInfo declaration into the
- class, initialized by IMPLEMENT_DYNAMIC_CLASS. When initialized, the
- wxClassInfo object inserts itself into a linked list (accessed through
- wxClassInfo::first and wxClassInfo::next pointers). The linked list
- is fully created by the time all global initialisation is done.
- IMPLEMENT_DYNAMIC_CLASS is a macro that not only initialises the static
- wxClassInfo member, but defines a global function capable of creating a
- dynamic object of the class in question. A pointer to this function is
- stored in wxClassInfo, and is used when an object should be created
- dynamically.
- wxObject::IsKindOf uses the linked list of
- wxClassInfo. It takes a wxClassInfo argument, so use CLASSINFO(className)
- to return an appropriate wxClassInfo pointer to use in this function.
- The function #wxCreateDynamicObject can be used
- to construct a new object of a given type, by supplying a string name.
- If you have a pointer to the wxClassInfo object instead, then you
- can simply call wxClassInfo::CreateObject.
- #wxClassInfo
- #Example
-
-
- @section wxclassinfooverview wxClassInfo
-
- #Runtime class information (aka RTTI) overview
- Class: #wxClassInfo
- This class stores meta-information about classes. An application
- may use macros such as DECLARE_DYNAMIC_CLASS and IMPLEMENT_DYNAMIC_CLASS
- to record run-time information about a class, including:
-
-
- its position in the inheritance hierarchy;
- the base class name(s) (up to two base classes are permitted);
- a string representation of the class name;
- a function that can be called to construct an instance of this class.
-
-
- The DECLARE_... macros declare a static wxClassInfo variable in a class, which is initialized
- by macros of the form IMPLEMENT_... in the implementation C++ file. Classes whose instances may be
- constructed dynamically are given a global constructor function which returns a new object.
- You can get the wxClassInfo for a class by using the CLASSINFO macro, e.g. CLASSINFO(wxFrame).
- You can get the wxClassInfo for an object using wxObject::GetClassInfo.
- See also #wxObject and #wxCreateDynamicObject.
-
- @section runtimeclassinformationexample Example
-
- In a header file frame.h:
-
- @code
- class wxFrame : public wxWindow
- {
- DECLARE_DYNAMIC_CLASS(wxFrame)
-
- private:
- wxString m_title;
-
- public:
- ...
- };
- @endcode
-
- In a C++ file frame.cpp:
-
- @code
- IMPLEMENT_DYNAMIC_CLASS(wxFrame, wxWindow)
-
- wxFrame::wxFrame()
- {
- ...
- }
- @endcode
-
- */
+/**
+@page overview_rtti Runtime Type Information (RTTI)
+
+@li @ref overview_rtti_intro
+@li @ref overview_rtti_classinfo
+@li @ref overview_rtti_example
+
+@see
+
+@li wxObject
+@li wxClassInfo
+
+
+<hr>
+
+
+@section overview_rtti_intro Introduction
+
+One of the failings of C++ used to be that no runtime information was provided
+about a class and its position in the inheritance hierarchy. Another, which
+still persists, is that instances of a class cannot be created just by knowing
+the name of a class, which makes facilities such as persistent storage hard to
+implement.
+
+Most C++ GUI frameworks overcome these limitations by means of a set of macros
+and functions and wxWidgets is no exception. As it originated before the
+addition of RTTI to the C++ standard and as support for it is still missing
+from some (albeit old) compilers, wxWidgets doesn't (yet) use it, but provides
+it's own macro-based RTTI system.
+
+In the future, the standard C++ RTTI will be used though and you're encouraged
+to use whenever possible the wxDynamicCast macro which, for the implementations
+that support it, is defined just as dynamic_cast and uses wxWidgets RTTI for
+all the others. This macro is limited to wxWidgets classes only and only works
+with pointers (unlike the real dynamic_cast which also accepts references).
+
+Each class that you wish to be known to the type system should have a macro
+such as DECLARE_DYNAMIC_CLASS just inside the class declaration. The macro
+IMPLEMENT_DYNAMIC_CLASS should be in the implementation file. Note that these
+are entirely optional; use them if you wish to check object types, or create
+instances of classes using the class name. However, it is good to get into the
+habit of adding these macros for all classes.
+
+Variations on these macros are used for multiple inheritance, and abstract
+classes that cannot be instantiated dynamically or otherwise.
+
+DECLARE_DYNAMIC_CLASS inserts a static wxClassInfo declaration into the class,
+initialized by IMPLEMENT_DYNAMIC_CLASS. When initialized, the wxClassInfo
+object inserts itself into a linked list (accessed through wxClassInfo::first
+and wxClassInfo::next pointers). The linked list is fully created by the time
+all global initialisation is done.
+
+IMPLEMENT_DYNAMIC_CLASS is a macro that not only initialises the static
+wxClassInfo member, but defines a global function capable of creating a dynamic
+object of the class in question. A pointer to this function is stored in
+wxClassInfo, and is used when an object should be created dynamically.
+
+wxObject::IsKindOf uses the linked list of wxClassInfo. It takes a wxClassInfo
+argument, so use CLASSINFO(className) to return an appropriate wxClassInfo
+pointer to use in this function.
+
+The function wxCreateDynamicObject can be used to construct a new object of a
+given type, by supplying a string name. If you have a pointer to the
+wxClassInfo object instead, then you can simply call wxClassInfo::CreateObject.
+
+
+@section overview_rtti_classinfo wxClassInfo
+
+This class stores meta-information about classes. An application may use macros
+such as DECLARE_DYNAMIC_CLASS and IMPLEMENT_DYNAMIC_CLASS to record runtime
+information about a class, including:
+
+@li It's position in the inheritance hierarchy.
+@li The base class name(s) (up to two base classes are permitted).
+@li A string representation of the class name.
+@li A function that can be called to construct an instance of this class.
+
+The DECLARE_... macros declare a static wxClassInfo variable in a class, which
+is initialized by macros of the form IMPLEMENT_... in the implementation C++
+file. Classes whose instances may be constructed dynamically are given a global
+constructor function which returns a new object.
+
+You can get the wxClassInfo for a class by using the CLASSINFO macro, e.g.
+CLASSINFO(wxFrame). You can get the wxClassInfo for an object using
+wxObject::GetClassInfo.
+
+@see
+
+@li wxObject
+@li wxCreateDynamicObject
+
+
+@section overview_rtti_example Example
+
+In a header file frame.h:
+
+@code
+class wxFrame : public wxWindow
+{
+ DECLARE_DYNAMIC_CLASS(wxFrame)
+
+private:
+ wxString m_title;
+
+public:
+...
+};
+@endcode
+
+In a C++ file frame.cpp:
+
+@code
+IMPLEMENT_DYNAMIC_CLASS(wxFrame, wxWindow)
+
+wxFrame::wxFrame()
+{
+...
+}
+@endcode
+
+*/
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