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     wxVariant(bool val, const wxString& name = g_szNul);
  83     wxVariant(char val, const wxString& name = g_szNul);
  84     wxVariant(const wxString& val, const wxString& name = g_szNul);
  85     wxVariant(const char* val, const wxString& name = g_szNul); // Necessary or VC++ assumes bool!
  86     wxVariant(const wxStringList& val, const wxString& name = g_szNul);
  87     wxVariant(const wxList& val, const wxString& name = g_szNul); // List of variants
  88 #if wxUSE_TIMEDATE
  89     wxVariant(const wxTime& val, const wxString& name = g_szNul); // Time
  90     wxVariant(const wxDate& val, const wxString& name = g_szNul); // Date
  91 #endif
  92     wxVariant(void* ptr, const wxString& name = g_szNul); // void* (general purpose)
  93     wxVariant(wxVariantData* data, const wxString& name = g_szNul); // User-defined data
  94     wxVariant(const wxVariant& variant);
  95     ~wxVariant();
  96
  97 // Generic operators
  98     // Assignment
  99     void operator= (const wxVariant& variant);
 100
 101     // Assignment using data, e.g.
 102     // myVariant = new wxStringVariantData("hello");
 103     void operator= (wxVariantData* variantData);
 104     bool operator== (const wxVariant& variant) const;
 105     bool operator!= (const wxVariant& variant) const;
 106
 107 // Specific operators
 108     bool operator== (double value) const;
 109     bool operator!= (double value) const;
 110     void operator= (double value) ;
 111     bool operator== (long value) const;
 112     bool operator!= (long value) const;
 113     void operator= (long value) ;
 114     bool operator== (char value) const;
 115     bool operator!= (char value) const;
 116     void operator= (char value) ;
 117     bool operator== (bool value) const;
 118     bool operator!= (bool value) const;
 119     void operator= (bool value) ;
 120     bool operator== (const wxString& value) const;
 121     bool operator!= (const wxString& value) const;
 122     void operator= (const wxString& value) ;
 123     void operator= (const char* value) ; // Necessary or VC++ assumes bool!
 124     bool operator== (const wxStringList& value) const;
 125     bool operator!= (const wxStringList& value) const;
 126     void operator= (const wxStringList& value) ;
 127     bool operator== (const wxList& value) const;
 128     bool operator!= (const wxList& value) const;
 129     void operator= (const wxList& value) ;
 130 #if wxUSE_TIMEDATE
 131     bool operator== (const wxTime& value) const;
 132     bool operator!= (const wxTime& value) const;
 133     void operator= (const wxTime& value) ;
 134     bool operator== (const wxDate& value) const;
 135     bool operator!= (const wxDate& value) const;
 136     void operator= (const wxDate& value) ;
 137 #endif
 138     bool operator== (void* value) const;
 139     bool operator!= (void* value) const;
 140     void operator= (void* value) ;
 141
 142     // Treat a list variant as an array
 143     wxVariant operator[] (size_t idx) const;
 144     wxVariant& operator[] (size_t idx) ;
 145
 146     // Implicit conversion to a wxString
 147     inline operator wxString () const {  return MakeString(); }
 148     wxString MakeString() const;
 149
 150     // Other implicit conversions
 151     inline operator double () const {  return GetDouble(); }
 152     inline operator char () const {  return GetChar(); }
 153     inline operator long () const {  return GetLong(); }
 154     inline operator bool () const {  return GetBool(); }
 155 #if wxUSE_TIMEDATE
 156     inline operator wxTime () const {  return GetTime(); }
 157     inline operator wxDate () const {  return GetDate(); }
 158 #endif
 159     inline operator void* () const {  return GetVoidPtr(); }
 160
 161 // Accessors
 162     // Sets/gets name
 163     inline void SetName(const wxString& name) { m_name = name; }
 164     inline const wxString& GetName() const { return m_name; }
 165
 166     // Tests whether there is data
 167     inline bool IsNull() const { return (m_data == (wxVariantData*) NULL); }
 168
 169     wxVariantData* GetData() const { return m_data; }
 170     void SetData(wxVariantData* data) ;
 171
 172     // Returns a string representing the type of the variant,
 173     // e.g. "string", "bool", "stringlist", "list", "double", "long"
 174     wxString GetType() const;
 175
 176     bool IsType(const wxString& type) const;
 177
 178     // Return the number of elements in a list
 179     int GetCount() const;
 180
 181 // Value accessors
 182     double GetReal() const ;
 183     inline double GetDouble() const { return GetReal(); };
 184     long GetInteger() const ;
 185     inline long GetLong() const { return GetInteger(); };
 186     char GetChar() const ;
 187     bool GetBool() const ;
 188     wxString GetString() const ;
 189     wxList& GetList() const ;
 190     wxStringList& GetStringList() const ;
 191 #if wxUSE_TIMEDATE
 192     wxTime GetTime() const ;
 193     wxDate GetDate() const ;
 194 #endif
 195     void* GetVoidPtr() const ;
 196
 197 // Operations
 198     // Make NULL (i.e. delete the data)
 199     void MakeNull();
 200
 201     // Make empty list
 202     void NullList();
 203
 204     // Append to list
 205     void Append(const wxVariant& value);
 206
 207     // Insert at front of list
 208     void Insert(const wxVariant& value);
 209
 210     // Returns TRUE if the variant is a member of the list
 211     bool Member(const wxVariant& value) const;
 212
 213     // Deletes the nth element of the list
 214     bool Delete(int item);
 215
 216     // Clear list
 217     void ClearList();
 218
 219 // Implementation
 220 protected:
 221 // Type conversion
 222     bool Convert(long* value) const;
 223     bool Convert(bool* value) const;
 224     bool Convert(double* value) const;
 225     bool Convert(wxString* value) const;
 226     bool Convert(char* value) const;
 227 #if wxUSE_TIMEDATE
 228     bool Convert(wxTime* value) const;
 229     bool Convert(wxDate* value) const;
 230 #endif
 231
 232 // Attributes
 233 protected:
 234     wxVariantData*  m_data;
 235     wxString        m_name;
 236 };
 237
 238 extern wxVariant WXDLLEXPORT wxNullVariant;
 239
 240 #endif
 241     // _WX_VARIANT_H_