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.
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. Additionly, the
-conveniance 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 modifiying either the wxVariant or the class
-to be stored by wxVariant. Since assignement operators cannot be declared outside
-the class, the shift left operators are used like this:
+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)
-
+ IMPLEMENT_VARIANT_OBJECT(MyClass)
+
// in the user code
wxVariant variant;
MyClass value;
variant << value;
-
+
// or
value << variant;
\end{verbatim}
\begin{verbatim}
IMPLEMENT_VARIANT_OBJECT(wxColour)
-IMPLEMENT_VARIANT_OBJECT(wxPen)
-IMPLEMENT_VARIANT_OBJECT(wxBrush)
IMPLEMENT_VARIANT_OBJECT(wxImage)
IMPLEMENT_VARIANT_OBJECT(wxIcon)
IMPLEMENT_VARIANT_OBJECT(wxBitmap)
\end{verbatim}
+Note that as of wxWidgets 2.9.0, wxVariantData no longer inherits from wxObject
+and wxVariant no longer uses the type-unsafe wxList class for list
+operations but the type-safe wxVariantList class. Also, wxVariantData now
+supports the Clone function for implementing the \helpref{wxVariant::Unshare}{wxvariantunshare} function.
+Clone is implemented automatically by IMPLEMENT\_VARIANT\_OBJECT.
+
+Since wxVariantData no longer derives from wxObject, any code that tests the type
+of the data using wxDynamicCast will require adjustment. You can use the macro
+wxDynamicCastVariantData with the same arguments as wxDynamicCast, to use C++ RTTI
+type information instead of wxWidgets RTTI.
+
\wxheading{Derived from}
\helpref{wxObject}{wxobject}
<wx/variant.h>
+\wxheading{Library}
+
+\helpref{wxBase}{librarieslist}
+
\wxheading{See also}
\helpref{wxVariantData}{wxvariantdata}
\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.
Construction from a double-precision floating point value.
-\func{}{wxVariant}{\param{const wxList\&}{ value}, \param{const wxString\& }{name = ``"}}
+\func{}{wxVariant}{\param{const wxVariantList\&}{ value}, \param{const wxString\& }{name = ``"}}
Construction from a list of wxVariant objects. This constructor
copies {\it value}, the application is still responsible for
\func{}{wxVariant}{\param{DATE\_STRUCT*}{ val}, \param{const wxString\& }{name = ``"}}
-Construction from a odbc date value. Represented internally by a \helpref{wxDateTime}{wxdatetime} value.
+Construction from a ODBC date value. Represented internally by a \helpref{wxDateTime}{wxdatetime} value.
\func{}{wxVariant}{\param{TIME\_STRUCT*}{ val}, \param{const wxString\& }{name = ``"}}
-Construction from a odbc time value. Represented internally by a \helpref{wxDateTime}{wxdatetime} value.
+Construction from a ODBC time value. Represented internally by a \helpref{wxDateTime}{wxdatetime} value.
\func{}{wxVariant}{\param{TIMESTAMP\_STRUCT*}{ val}, \param{const wxString\& }{name = ``"}}
-Construction from a odbc timestamp value. Represented internally by a \helpref{wxDateTime}{wxdatetime} value.
+Construction from a ODBC timestamp value. Represented internally by a \helpref{wxDateTime}{wxdatetime} value.
\membersection{wxVariant::\destruct{wxVariant}}\label{wxvariantdtor}
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.
Returns the floating point value.
+\membersection{wxVariant::GetList}\label{wxvariantgetlist}
+
+\constfunc{wxVariantList &}{GetList}{\void}
+
+Returns a reference to the wxVariantList class used by
+wxVariant if this wxVariant is currently a list of variants.
+
\membersection{wxVariant::GetLong}\label{wxvariantgetlong}
\constfunc{long}{GetLong}{\void}
\constfunc{wxString}{GetType}{\void}
-Returns the value type as a string. The built-in types are: bool, char, date, double, list, long, string, stringlist, time, void*.
+Returns the value type as a string. The built-in types are: bool, char, datetime, double, list, long, string, arrstring, void*.
If the variant is null, the value type returned is the string ``null" (not the empty string).
Sets the internal variant data, deleting the existing data if there is any.
+\membersection{wxVariant::Unshare}\label{wxvariantunshare}
+
+\func{bool}{Unshare}{\void}
+
+Makes sure that any data associated with this variant is not shared with other
+variants. For this to work, \helpref{wxVariantData::Clone}{wxvariantdataclone} must
+be implemented for the data types you are working with. Clone is implemented
+for all the default data types.
+
\membersection{wxVariant::operator $=$}\label{wxvariantassignment}
\func{void}{operator $=$}{\param{const wxVariant\& }{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{wxObject* }{value}}
-\func{void}{operator $=$}{\param{const wxList\& }{value}}
+\func{void}{operator $=$}{\param{const wxVariantList\& }{value}}
\func{void}{operator $=$}{\param{const wxDateTime\& }{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{wxObject* }{value}}
-\constfunc{bool}{operator $==$}{\param{const wxList\& }{value}}
+\constfunc{bool}{operator $==$}{\param{const wxVariantList\& }{value}}
\constfunc{bool}{operator $==$}{\param{const wxArrayString\& }{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}}
\constfunc{bool}{operator $!=$}{\param{wxObject* }{value}}
-\constfunc{bool}{operator $!=$}{\param{const wxList\& }{value}}
+\constfunc{bool}{operator $!=$}{\param{const wxVariantList\& }{value}}
\constfunc{bool}{operator $!=$}{\param{const wxArrayString\& }{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.
instance. Instead, \helpref{DecRef}{wxvariantdatadecref} will delete the object automatically
when the reference count reaches zero.
+\wxheading{Include files}
+
+<wx/variant.h>
+
\wxheading{Derived from}
-\helpref{wxObject}{wxobject}
+No base class
-\wxheading{Include files}
+\wxheading{Library}
-<wx/variant.h>
+\helpref{wxBase}{librarieslist}
\wxheading{See also}
Default constructor.
+\membersection{wxVariantData::Clone}\label{wxvariantdataclone}
+
+\constfunc{wxVariantData*}{Clone}{\void}
+
+This function can be overridden to clone the data.
+Implement Clone if you wish \helpref{wxVariant::Unshare}{wxvariantunshare} to work
+for your data. This function is implemented for all built-in data types.
+
\membersection{wxVariantData::DecRef}\label{wxvariantdatadecref}
\func{void}{DecRef}{\void}
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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