The {\bf wxVariant} class represents a container for any type.
A variant's value can be changed at run time, possibly to a different type of value.
-As standard, wxVariant can store values of type bool, char, double, long, string,
+As standard, wxVariant can store values of type bool, wxChar, double, long, string,
string list, time, date, void pointer, list of strings, and list of variants.
However, an application can extend wxVariant's capabilities by deriving from the
class \helpref{wxVariantData}{wxvariantdata} and using the wxVariantData form of
object, unlike the case for basic data types where convenience functions such as
\helpref{GetLong}{wxvariantgetlong} can be used.
-Pointers to any \helpref{wxObject}{helpref} derived class can also easily be stored
+Pointers to any \helpref{wxObject}{wxobject} derived class can also easily be stored
in a wxVariant. wxVariant will then use wxWidgets' built-in RTTI system to set the
type name (returned by \helpref{GetType}{wxvariantgettype}) and to perform
type-safety checks at runtime.
This class is useful for reducing the programming for certain tasks, such as an editor
for different data types, or a remote procedure call protocol.
-An optional name member is associated with a wxVariant. This might be used, for example, in CORBA
-or OLE automation classes, where named parameters are required.
-
-Note that as of wxWidgets 2.7.1, wxVariant is reference counted.
+An optional name member is associated with a wxVariant. This might be used, for example,
+in CORBA or OLE automation classes, where named parameters are required.
+
+Note that as of wxWidgets 2.7.1, wxVariant is \helpref{reference counted}{trefcount}.
+Additionally, the convenience macros {\bf DECLARE\_VARIANT\_OBJECT} and
+{\bf IMPLEMENT\_VARIANT\_OBJECT} were added so that adding (limited) support
+for conversion to and from wxVariant can be very easily implemented without modifying
+either wxVariant or the class to be stored by wxVariant. Since assignment operators
+cannot be declared outside the class, the shift left operators are used like this:
+
+\begin{verbatim}
+ // in the header file
+ DECLARE_VARIANT_OBJECT(MyClass)
+
+ // in the implementation file
+ IMPLMENT_VARIANT_OBJECT(MyClass)
+
+ // in the user code
+ wxVariant variant;
+ MyClass value;
+ variant << value;
+
+ // or
+ value << variant;
+\end{verbatim}
+
+For this to work, MyClass must derive from \helpref{wxObject}{wxobject}, implement
+the \helpref{wxWidgets RTTI system}{runtimeclassoverview}
+and support the assignment operator and equality operator for itself. Ideally, it
+should also be reference counted to make copying operations cheap and fast. This
+can be most easily implemented using the reference counting support offered by
+\helpref{wxObject}{wxobject} itself. By default, wxWidgets already implements
+the shift operator conversion for a few of its drawing related classes:
+
+\begin{verbatim}
+IMPLEMENT_VARIANT_OBJECT(wxColour)
+IMPLEMENT_VARIANT_OBJECT(wxImage)
+IMPLEMENT_VARIANT_OBJECT(wxIcon)
+IMPLEMENT_VARIANT_OBJECT(wxBitmap)
+\end{verbatim}
\wxheading{Derived from}
\func{}{wxVariant}{\param{const wxVariant\& }{variant}}
-Copy constructor.
+Copy constructor, uses \helpref{reference counting}{trefcount}.
-\func{}{wxVariant}{\param{const char*}{ value}, \param{const wxString\& }{name = ``"}}
+\func{}{wxVariant}{\param{const wxChar*}{ value}, \param{const wxString\& }{name = ``"}}
\func{}{wxVariant}{\param{const wxString\&}{ value}, \param{const wxString\& }{name = ``"}}
Construction from a string value.
-\func{}{wxVariant}{\param{char}{ value}, \param{const wxString\& }{name = ``"}}
+\func{}{wxVariant}{\param{wxChar}{ value}, \param{const wxString\& }{name = ``"}}
Construction from a character value.
Note that destructor is protected, so wxVariantData cannot usually
be deleted. Instead, \helpref{DecRef}{wxvariantdatadecref} should be called.
+See \helpref{reference-counted object destruction}{refcountdestruct} for more info.
\membersection{wxVariant::Append}\label{wxvariantappend}
\constfunc{bool}{Convert}{\param{wxString*}{ value}}
-\constfunc{bool}{Convert}{\param{char*}{ value}}
+\constfunc{bool}{Convert}{\param{wxChar*}{ value}}
\constfunc{bool}{Convert}{\param{wxDateTime*}{ value}}
\membersection{wxVariant::GetChar}\label{wxvariantgetchar}
-\constfunc{char}{GetChar}{\void}
+\constfunc{wxChar}{GetChar}{\void}
Returns the character value.
\func{void}{operator $=$}{\param{const wxString\& }{value}}
-\func{void}{operator $=$}{\param{const char* }{value}}
+\func{void}{operator $=$}{\param{const wxChar* }{value}}
-\func{void}{operator $=$}{\param{char }{value}}
+\func{void}{operator $=$}{\param{wxChar }{value}}
\func{void}{operator $=$}{\param{const long }{value}}
\func{void}{operator $=$}{\param{const TIMESTAMP\_STRUCT* }{value}}
-Assignment operators.
+Assignment operators, using \helpref{reference counting}{trefcount} when possible.
\membersection{wxVariant::operator $==$}\label{wxvarianteq}
\constfunc{bool}{operator $==$}{\param{const wxString\& }{value}}
-\constfunc{bool}{operator $==$}{\param{const char* }{value}}
+\constfunc{bool}{operator $==$}{\param{const wxChar* }{value}}
-\constfunc{bool}{operator $==$}{\param{char }{value}}
+\constfunc{bool}{operator $==$}{\param{wxChar }{value}}
\constfunc{bool}{operator $==$}{\param{const long }{value}}
\constfunc{bool}{operator $!=$}{\param{const wxString\& }{value}}
-\constfunc{bool}{operator $!=$}{\param{const char* }{value}}
+\constfunc{bool}{operator $!=$}{\param{const wxChar* }{value}}
-\constfunc{bool}{operator $!=$}{\param{char }{value}}
+\constfunc{bool}{operator $!=$}{\param{wxChar }{value}}
\constfunc{bool}{operator $!=$}{\param{const long }{value}}
Returns a reference to the value at {\it idx} (zero-based). This can be used
to change the value at this index.
-\membersection{wxVariant::operator char}\label{wxvariantchar}
+\membersection{wxVariant::operator wxChar}\label{wxvariantchar}
-\constfunc{char}{operator char}{\void}
+\constfunc{char}{operator wxChar}{\void}
-Operator for implicit conversion to a char, using \helpref{wxVariant::GetChar}{wxvariantgetchar}.
+Operator for implicit conversion to a wxChar, using \helpref{wxVariant::GetChar}{wxvariantgetchar}.
\membersection{wxVariant::operator double}\label{wxvariantdouble}
Operator for implicit conversion to a pointer to a \helpref{wxDateTime}{wxdatetime}, using \helpref{wxVariant::GetDateTime}{wxvariantgetdatetime}.
+
+
+%% wxVariantData
+
+
\section{\class{wxVariantData}}\label{wxvariantdata}
-The {\bf wxVariantData} is used to implement a new type for wxVariant. Derive from wxVariantData,
-and override the pure virtual functions.
+The {\bf wxVariantData} class is used to implement a new type for \helpref{wxVariant}{wxvariant}.
+Derive from wxVariantData, and override the pure virtual functions.
-wxVariantData is reference counted, but you don't normally have to care about this, as
-wxVariant manages the count automatically. However, incase your application needs to take
+wxVariantData is \helpref{reference counted}{refcount}, but you don't normally have to care about this,
+as wxVariant manages the count automatically. However, in case your application needs to take
ownership of wxVariantData, be aware that the object is created with reference count of 1,
and passing it to wxVariant will not increase this. In other words, \helpref{IncRef}{wxvariantdataincref}
needs to be called only if you both take ownership of wxVariantData and pass it to a wxVariant.
automatically deleted.
Note that destructor of wxVariantData is protected, so delete
-cannot be used as normal. Instead, DecRef should be called.
+cannot be used as normal. Instead, \helpref{DecRef}{wxvariantdatadecref} should be called.
+
+
\membersection{wxVariantData::Eq}\label{wxvariantdataeq}
\helpref{RTTI overview}{runtimeclassoverview}\\
\helpref{wxDynamicCast}{wxdynamiccast}
+
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