include/wx/variant.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        variant.h
   3 // Purpose:     wxVariant class, container for any type
   4 // Author:      Julian Smart
   5 // Modified by:
   6 // Created:     10/09/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c)
   9 // Licence:     wxWindows licence
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 #ifndef _WX_VARIANT_H_
  13 #define _WX_VARIANT_H_
  14
  15 #ifdef __GNUG__
  16 #pragma interface "variant.h"
  17 #endif
  18
  19 #include "wx/defs.h"
  20 #include "wx/object.h"
  21 #include "wx/string.h"
  22 #include "wx/list.h"
  23
  24 #if wxUSE_TIMEDATE
  25     #include "wx/time.h"
  26     #include "wx/date.h"
  27 #endif // time/date
  28
  29 #include "wx/ioswrap.h"
  30
  31 /*
  32  * wxVariantData stores the actual data in a wxVariant object,
  33  * to allow it to store any type of data.
  34  * Derive from this to provide custom data handling.
  35  *
  36  * TODO: in order to replace wxPropertyValue, we would need
  37  * to consider adding constructors that take pointers to C++ variables,
  38  * or removing that functionality from the wxProperty library.
  39  * Essentially wxPropertyValue takes on some of the wxValidator functionality
  40  * by storing pointers and not just actual values, allowing update of C++ data
  41  * to be handled automatically. Perhaps there's another way of doing this without
  42  * overloading wxVariant with unnecessary functionality.
  43  */
  44
  45 class WXDLLEXPORT wxVariantData: public wxObject
  46 {
  47 DECLARE_ABSTRACT_CLASS(wxVariantData)
  48 public:
  49
  50 // Construction & destruction
  51     wxVariantData() {};
  52
  53 // Override these to provide common functionality
  54     // Copy to data
  55     virtual void Copy(wxVariantData& data) = 0;
  56     virtual bool Eq(wxVariantData& data) const = 0;
  57     virtual bool Write(ostream& str) const = 0;
  58     virtual bool Write(wxString& str) const = 0;
  59     virtual bool Read(istream& str) = 0;
  60     virtual bool Read(wxString& str) = 0;
  61     // What type is it? Return a string name.
  62     virtual wxString GetType() const = 0;
  63 };
  64
  65 /*
  66  * wxVariant can store any kind of data, but has some basic types
  67  * built in.
  68  * NOTE: this eventually should have a reference-counting implementation.
  69  * PLEASE, if you change it to ref-counting, make sure it doesn't involve bloating
  70  * this class too much.
  71  */
  72
  73 class WXDLLEXPORT wxVariant: public wxObject
  74 {
  75 DECLARE_DYNAMIC_CLASS(wxVariant)
  76 public:
  77
  78 // Construction & destruction
  79     wxVariant();
  80     wxVariant(double val, const wxString& name = g_szNul);
  81     wxVariant(long val, const wxString& name = g_szNul);
  82 #ifdef HAVE_BOOL
  83     wxVariant(bool val, const wxString& name = g_szNul);
  84 #endif
  85     wxVariant(char val, const wxString& name = g_szNul);
  86     wxVariant(const wxString& val, const wxString& name = g_szNul);
  87     wxVariant(const char* val, const wxString& name = g_szNul); // Necessary or VC++ assumes bool!
  88     wxVariant(const wxStringList& val, const wxString& name = g_szNul);
  89     wxVariant(const wxList& val, const wxString& name = g_szNul); // List of variants
  90 #if wxUSE_TIMEDATE
  91     wxVariant(const wxTime& val, const wxString& name = g_szNul); // Time
  92     wxVariant(const wxDate& val, const wxString& name = g_szNul); // Date
  93 #endif
  94     wxVariant(void* ptr, const wxString& name = g_szNul); // void* (general purpose)
  95     wxVariant(wxVariantData* data, const wxString& name = g_szNul); // User-defined data
  96     wxVariant(const wxVariant& variant);
  97     ~wxVariant();
  98
  99 // Generic operators
 100     // Assignment
 101     void operator= (const wxVariant& variant);
 102
 103     // Assignment using data, e.g.
 104     // myVariant = new wxStringVariantData("hello");
 105     void operator= (wxVariantData* variantData);
 106     bool operator== (const wxVariant& variant) const;
 107     bool operator!= (const wxVariant& variant) const;
 108
 109 // Specific operators
 110     bool operator== (double value) const;
 111     bool operator!= (double value) const;
 112     void operator= (double value) ;
 113     bool operator== (long value) const;
 114     bool operator!= (long value) const;
 115     void operator= (long value) ;
 116     bool operator== (char value) const;
 117     bool operator!= (char value) const;
 118     void operator= (char value) ;
 119 #ifdef HAVE_BOOL
 120     bool operator== (bool value) const;
 121     bool operator!= (bool value) const;
 122     void operator= (bool value) ;
 123 #endif
 124     bool operator== (const wxString& value) const;
 125     bool operator!= (const wxString& value) const;
 126     void operator= (const wxString& value) ;
 127     void operator= (const char* value) ; // Necessary or VC++ assumes bool!
 128     bool operator== (const wxStringList& value) const;
 129     bool operator!= (const wxStringList& value) const;
 130     void operator= (const wxStringList& value) ;
 131     bool operator== (const wxList& value) const;
 132     bool operator!= (const wxList& value) const;
 133     void operator= (const wxList& value) ;
 134 #if wxUSE_TIMEDATE
 135     bool operator== (const wxTime& value) const;
 136     bool operator!= (const wxTime& value) const;
 137     void operator= (const wxTime& value) ;
 138     bool operator== (const wxDate& value) const;
 139     bool operator!= (const wxDate& value) const;
 140     void operator= (const wxDate& value) ;
 141 #endif
 142     bool operator== (void* value) const;
 143     bool operator!= (void* value) const;
 144     void operator= (void* value) ;
 145
 146     // Treat a list variant as an array
 147     wxVariant operator[] (size_t idx) const;
 148     wxVariant& operator[] (size_t idx) ;
 149
 150     // Implicit conversion to a wxString
 151     inline operator wxString () const {  return MakeString(); }
 152     wxString MakeString() const;
 153
 154     // Other implicit conversions
 155     inline operator double () const {  return GetDouble(); }
 156     inline operator char () const {  return GetChar(); }
 157     inline operator long () const {  return GetLong(); }
 158     inline operator bool () const {  return GetBool(); }
 159 #if wxUSE_TIMEDATE
 160     inline operator wxTime () const {  return GetTime(); }
 161     inline operator wxDate () const {  return GetDate(); }
 162 #endif
 163     inline operator void* () const {  return GetVoidPtr(); }
 164
 165 // Accessors
 166     // Sets/gets name
 167     inline void SetName(const wxString& name) { m_name = name; }
 168     inline const wxString& GetName() const { return m_name; }
 169
 170     // Tests whether there is data
 171     inline bool IsNull() const { return (m_data == (wxVariantData*) NULL); }
 172
 173     wxVariantData* GetData() const { return m_data; }
 174     void SetData(wxVariantData* data) ;
 175
 176     // Returns a string representing the type of the variant,
 177     // e.g. "string", "bool", "stringlist", "list", "double", "long"
 178     wxString GetType() const;
 179
 180     bool IsType(const wxString& type) const;
 181
 182     // Return the number of elements in a list
 183     int GetCount() const;
 184
 185 // Value accessors
 186     double GetReal() const ;
 187     inline double GetDouble() const { return GetReal(); };
 188     long GetInteger() const ;
 189     inline long GetLong() const { return GetInteger(); };
 190     char GetChar() const ;
 191     bool GetBool() const ;
 192     wxString GetString() const ;
 193     wxList& GetList() const ;
 194     wxStringList& GetStringList() const ;
 195 #if wxUSE_TIMEDATE
 196     wxTime GetTime() const ;
 197     wxDate GetDate() const ;
 198 #endif
 199     void* GetVoidPtr() const ;
 200
 201 // Operations
 202     // Make NULL (i.e. delete the data)
 203     void MakeNull();
 204
 205     // Make empty list
 206     void NullList();
 207
 208     // Append to list
 209     void Append(const wxVariant& value);
 210
 211     // Insert at front of list
 212     void Insert(const wxVariant& value);
 213
 214     // Returns TRUE if the variant is a member of the list
 215     bool Member(const wxVariant& value) const;
 216
 217     // Deletes the nth element of the list
 218     bool Delete(int item);
 219
 220     // Clear list
 221     void ClearList();
 222
 223 // Implementation
 224 protected:
 225 // Type conversion
 226     bool Convert(long* value) const;
 227     bool Convert(bool* value) const;
 228     bool Convert(double* value) const;
 229     bool Convert(wxString* value) const;
 230     bool Convert(char* value) const;
 231 #if wxUSE_TIMEDATE
 232     bool Convert(wxTime* value) const;
 233     bool Convert(wxDate* value) const;
 234 #endif
 235
 236 // Attributes
 237 protected:
 238     wxVariantData*  m_data;
 239     wxString        m_name;
 240 };
 241
 242 extern wxVariant WXDLLEXPORT wxNullVariant;
 243
 244 #endif
 245     // _WX_VARIANT_H_