wxWidgets/include/wx/variant.h
2003-08-09 12:38:21 +00:00

292 lines
9.7 KiB
C++

/////////////////////////////////////////////////////////////////////////////
// Name: variant.h
// Purpose: wxVariant class, container for any type
// Author: Julian Smart
// Modified by:
// Created: 10/09/98
// RCS-ID: $Id$
// Copyright: (c)
// Licence: wxWindows licence
/////////////////////////////////////////////////////////////////////////////
#ifndef _WX_VARIANT_H_
#define _WX_VARIANT_H_
#if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
#pragma interface "variant.h"
#endif
#include "wx/defs.h"
#include "wx/object.h"
#include "wx/string.h"
#include "wx/arrstr.h"
#include "wx/list.h"
#if wxUSE_DATETIME
#include "wx/datetime.h"
#endif // wxUSE_DATETIME
#if wxUSE_ODBC
#include "wx/db.h" // will #include sqltypes.h
#endif //ODBC
#include "wx/iosfwrap.h"
/*
* wxVariantData stores the actual data in a wxVariant object,
* to allow it to store any type of data.
* Derive from this to provide custom data handling.
*
* TODO: in order to replace wxPropertyValue, we would need
* to consider adding constructors that take pointers to C++ variables,
* or removing that functionality from the wxProperty library.
* Essentially wxPropertyValue takes on some of the wxValidator functionality
* by storing pointers and not just actual values, allowing update of C++ data
* to be handled automatically. Perhaps there's another way of doing this without
* overloading wxVariant with unnecessary functionality.
*/
class WXDLLIMPEXP_BASE wxVariantData: public wxObject
{
DECLARE_ABSTRACT_CLASS(wxVariantData)
public:
// Construction & destruction
wxVariantData() {};
// Override these to provide common functionality
// Copy to data
virtual void Copy(wxVariantData& data) = 0;
virtual bool Eq(wxVariantData& data) const = 0;
#if wxUSE_STD_IOSTREAM
virtual bool Write(wxSTD ostream& str) const = 0;
#endif
virtual bool Write(wxString& str) const = 0;
#if wxUSE_STD_IOSTREAM
virtual bool Read(wxSTD istream& str) = 0;
#endif
virtual bool Read(wxString& str) = 0;
// What type is it? Return a string name.
virtual wxString GetType() const = 0;
// If it based on wxObject return the ClassInfo.
virtual wxClassInfo* GetValueClassInfo() { return NULL; }
};
/*
* wxVariant can store any kind of data, but has some basic types
* built in.
* NOTE: this eventually should have a reference-counting implementation.
* PLEASE, if you change it to ref-counting, make sure it doesn't involve bloating
* this class too much.
*/
class WXDLLIMPEXP_BASE wxVariant: public wxObject
{
DECLARE_DYNAMIC_CLASS(wxVariant)
public:
// Construction & destruction
wxVariant();
wxVariant(double val, const wxString& name = wxEmptyString);
wxVariant(long val, const wxString& name = wxEmptyString);
#ifdef HAVE_BOOL
wxVariant(bool val, const wxString& name = wxEmptyString);
#endif
wxVariant(char val, const wxString& name = wxEmptyString);
wxVariant(const wxString& val, const wxString& name = wxEmptyString);
wxVariant(const wxChar* val, const wxString& name = wxEmptyString); // Necessary or VC++ assumes bool!
wxVariant(const wxStringList& val, const wxString& name = wxEmptyString);
wxVariant(const wxList& val, const wxString& name = wxEmptyString); // List of variants
wxVariant(void* ptr, const wxString& name = wxEmptyString); // void* (general purpose)
wxVariant(wxObject* ptr, const wxString& name = wxEmptyString); //wxObject
wxVariant(wxVariantData* data, const wxString& name = wxEmptyString); // User-defined data
//TODO: Need to document
#if wxUSE_DATETIME
wxVariant(const wxDateTime& val, const wxString& name = wxEmptyString); // Date
#endif // wxUSE_DATETIME
wxVariant(const wxArrayString& val, const wxString& name = wxEmptyString); // String array
#if wxUSE_ODBC
wxVariant(const DATE_STRUCT* valptr, const wxString& name = wxEmptyString); // DateTime
wxVariant(const TIME_STRUCT* valptr, const wxString& name = wxEmptyString); // DateTime
wxVariant(const TIMESTAMP_STRUCT* valptr, const wxString& name = wxEmptyString); // DateTime
#endif
//TODO: End of Need to document
wxVariant(const wxVariant& variant);
~wxVariant();
// Generic operators
// Assignment
void operator= (const wxVariant& variant);
//TODO: Need to document
#if wxUSE_DATETIME
bool operator== (const wxDateTime& value) const;
bool operator!= (const wxDateTime& value) const;
void operator= (const wxDateTime& value) ;
#endif // wxUSE_DATETIME
bool operator== (const wxArrayString& value) const;
bool operator!= (const wxArrayString& value) const;
void operator= (const wxArrayString& value) ;
#if wxUSE_ODBC
void operator= (const DATE_STRUCT* value) ;
void operator= (const TIME_STRUCT* value) ;
void operator= (const TIMESTAMP_STRUCT* value) ;
#endif
//TODO: End of Need to document
// Assignment using data, e.g.
// myVariant = new wxStringVariantData("hello");
void operator= (wxVariantData* variantData);
bool operator== (const wxVariant& variant) const;
bool operator!= (const wxVariant& variant) const;
// Specific operators
bool operator== (double value) const;
bool operator!= (double value) const;
void operator= (double value) ;
bool operator== (long value) const;
bool operator!= (long value) const;
void operator= (long value) ;
bool operator== (char value) const;
bool operator!= (char value) const;
void operator= (char value) ;
#ifdef HAVE_BOOL
bool operator== (bool value) const;
bool operator!= (bool value) const;
void operator= (bool value) ;
#endif
bool operator== (const wxString& value) const;
bool operator!= (const wxString& value) const;
void operator= (const wxString& value) ;
void operator= (const wxChar* value) ; // Necessary or VC++ assumes bool!
bool operator== (const wxStringList& value) const;
bool operator!= (const wxStringList& value) const;
void operator= (const wxStringList& value) ;
bool operator== (const wxList& value) const;
bool operator!= (const wxList& value) const;
void operator= (const wxList& value) ;
bool operator== (void* value) const;
bool operator!= (void* value) const;
void operator= (void* value) ;
// Treat a list variant as an array
wxVariant operator[] (size_t idx) const;
wxVariant& operator[] (size_t idx) ;
// Implicit conversion to a wxString
inline operator wxString () const { return MakeString(); }
wxString MakeString() const;
// Other implicit conversions
inline operator double () const { return GetDouble(); }
inline operator char () const { return GetChar(); }
inline operator long () const { return GetLong(); }
inline operator bool () const { return GetBool(); }
inline operator void* () const { return GetVoidPtr(); }
// No implicit conversion to wxObject, as that would really
// confuse people between conversion to our contained data
// and downcasting to see our base type.
//TODO: Need to document
#if wxUSE_DATETIME
inline operator wxDateTime () const { return GetDateTime(); }
#endif // wxUSE_DATETIME
//TODO: End of Need to document
// Accessors
// Sets/gets name
inline void SetName(const wxString& name) { m_name = name; }
inline const wxString& GetName() const { return m_name; }
// Tests whether there is data
inline bool IsNull() const { return (m_data == (wxVariantData*) NULL); }
wxVariantData* GetData() const { return m_data; }
void SetData(wxVariantData* data) ;
// Returns a string representing the type of the variant,
// e.g. "string", "bool", "stringlist", "list", "double", "long"
wxString GetType() const;
bool IsType(const wxString& type) const;
bool IsValueKindOf(const wxClassInfo* type) const;
// Return the number of elements in a list
int GetCount() const;
// Value accessors
double GetReal() const ;
inline double GetDouble() const { return GetReal(); };
long GetInteger() const ;
inline long GetLong() const { return GetInteger(); };
char GetChar() const ;
bool GetBool() const ;
wxString GetString() const ;
wxList& GetList() const ;
wxStringList& GetStringList() const ;
void* GetVoidPtr() const ;
wxObject* GetWxObjectPtr() ;
//TODO: Need to document
#if wxUSE_DATETIME
wxDateTime GetDateTime() const ;
#endif // wxUSE_DATETIME
wxArrayString GetArrayString() const;
//TODO: End of Need to document
// Operations
// Make NULL (i.e. delete the data)
void MakeNull();
// Make empty list
void NullList();
// Append to list
void Append(const wxVariant& value);
// Insert at front of list
void Insert(const wxVariant& value);
// Returns TRUE if the variant is a member of the list
bool Member(const wxVariant& value) const;
// Deletes the nth element of the list
bool Delete(int item);
// Clear list
void ClearList();
// Implementation
public:
// Type conversion
bool Convert(long* value) const;
bool Convert(bool* value) const;
bool Convert(double* value) const;
bool Convert(wxString* value) const;
bool Convert(char* value) const;
//TODO: Need to document
#if wxUSE_DATETIME
bool Convert(wxDateTime* value) const;
#endif // wxUSE_DATETIME
//TODO: End of Need to document
// Attributes
protected:
wxVariantData* m_data;
wxString m_name;
};
//Since we want type safety wxVariant we need to fetch and dynamic_cast
//in a seemingly safe way so the compiler can check, so we define
//a dynamic_cast /wxDynamicCast analogue.
#define wxGetVariantCast(var,classname) \
((classname*)(var.IsValueKindOf(&classname::sm_class##classname) ?\
var.GetWxObjectPtr() : NULL));
extern wxVariant WXDLLIMPEXP_BASE wxNullVariant;
#endif
// _WX_VARIANT_H_