Added wxVariantData::Clone and wxVariant::Unshare

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@49246 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

diff --git a/docs/changes.txt b/docs/changes.txt
index bc46d45cb3696f7680a69f0ec5719f848aa3881b..74998a35cab5dec77ad18790430d04ff9d14757d 100644 (file)
--- a/docs/changes.txt
+++ b/docs/changes.txt
@@ -111,6 +111,10 @@ Changes in behaviour which may result in compilation errors
 
 - Removed global GetLine() function from wx/protocol/protocol.h, use
   wxProtocol::ReadLine() instead.
 
 - Removed global GetLine() function from wx/protocol/protocol.h, use
   wxProtocol::ReadLine() instead.

+  
+- wxVariant no longer derives from wxObject. wxVariantData also no longer
+  derives from wxObject; instead of using wxDynamicCast with wxVariantData you
+  can use the macro wxDynamicCastVariantData with the same arguments.

 
 
 Deprecated methods and their replacements
 
 
 Deprecated methods and their replacements


@@ -156,6 +160,8 @@ All:
 - Documentation now includes the wx library in which each class is defined.
 - wxrc --gettext now generates references to source .xrc files (Heikki
   Linnakangas).
 - Documentation now includes the wx library in which each class is defined.
 - wxrc --gettext now generates references to source .xrc files (Heikki
   Linnakangas).

+- wxVariant::Unshare allows exclusive allocation of data that must be shared,
+  if the wxVariantData::Clone function is implemented.

 
 All (Unix):
 
 
 All (Unix):
 

diff --git a/docs/latex/wx/variant.tex b/docs/latex/wx/variant.tex
index 8343da9923e23a8c81a09f79ea0054d2321d8d6a..db82e17c9ecc8b1c80df22dbdb4062d04368879a 100644 (file)
--- a/docs/latex/wx/variant.tex
+++ b/docs/latex/wx/variant.tex
@@ -74,7 +74,14 @@ IMPLEMENT_VARIANT_OBJECT(wxBitmap)
 
 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
 
 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.
+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}
 
 
 \wxheading{Derived from}
 


@@ -364,6 +371,15 @@ is of type list, but the number of elements in the list is zero.
 
 Sets the internal variant data, deleting the existing data if there is any.
 
 
 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}}
 \membersection{wxVariant::operator $=$}\label{wxvariantassignment}
 
 \func{void}{operator $=$}{\param{const wxVariant\& }{value}}


@@ -544,6 +560,14 @@ No base class
 
 Default constructor.
 
 
 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}
 \membersection{wxVariantData::DecRef}\label{wxvariantdatadecref}
 
 \func{void}{DecRef}{\void}


@@ -555,7 +579,6 @@ Note that destructor of wxVariantData is protected, so delete
 cannot be used as normal. Instead, \helpref{DecRef}{wxvariantdatadecref} should be called.
 
 
 cannot be used as normal. Instead, \helpref{DecRef}{wxvariantdatadecref} should be called.
 
 

-

 \membersection{wxVariantData::Eq}\label{wxvariantdataeq}
 
 \constfunc{bool}{Eq}{\param{wxVariantData\&}{ data}}
 \membersection{wxVariantData::Eq}\label{wxvariantdataeq}
 
 \constfunc{bool}{Eq}{\param{wxVariantData\&}{ data}}

diff --git a/include/wx/variant.h b/include/wx/variant.h
index dffe0a0190da7921a1a17240fe445c26e1e89225..31fbbc8acb01c3ab01678dc8f3d05673b96a6688 100644 (file)
--- a/include/wx/variant.h
+++ b/include/wx/variant.h
@@ -81,6 +81,10 @@ public:
     // If it based on wxObject return the ClassInfo.
     virtual wxClassInfo* GetValueClassInfo() { return NULL; }
 
     // If it based on wxObject return the ClassInfo.
     virtual wxClassInfo* GetValueClassInfo() { return NULL; }
 

+    // Implement this to make wxVariant::AllocExcusive work. Returns
+    // a copy of the data.
+    virtual wxVariantData* Clone() const { return NULL; }
+

     void IncRef() { m_count++; }
     void DecRef()
     {
     void IncRef() { m_count++; }
     void DecRef()
     {


@@ -104,7 +108,7 @@ private:
  * wxVariant can store any kind of data, but has some basic types
  * built in.
  */
  * wxVariant can store any kind of data, but has some basic types
  * built in.
  */

- 
+

 class WXDLLIMPEXP_FWD_BASE wxVariant;
 
 WX_DECLARE_LIST_WITH_DECL(wxVariant, wxVariantList, class WXDLLIMPEXP_BASE);
 class WXDLLIMPEXP_FWD_BASE wxVariant;
 
 WX_DECLARE_LIST_WITH_DECL(wxVariant, wxVariantList, class WXDLLIMPEXP_BASE);


@@ -146,6 +150,9 @@ public:
     // destroy a reference
     void UnRef();
 
     // destroy a reference
     void UnRef();
 

+    // ensure that the data is exclusive to this variant, and not shared
+    bool Unshare();
+

     // Make NULL (i.e. delete the data)
     void MakeNull();
 
     // Make NULL (i.e. delete the data)
     void MakeNull();
 


@@ -365,6 +372,8 @@ public:\
 \
     virtual wxString GetType() const; \
     virtual wxClassInfo* GetValueClassInfo(); \
 \
     virtual wxString GetType() const; \
     virtual wxClassInfo* GetValueClassInfo(); \

+\
+    virtual wxVariantData* Clone() const { return new classname##VariantData(m_value); } \

 \
 protected:\
     classname m_value; \
 \
 protected:\
     classname m_value; \


@@ -436,6 +445,9 @@ bool classname##VariantData::Eq(wxVariantData& data) const \
     ((classname*)(var.IsValueKindOf(&classname::ms_classInfo) ?\
                   var.GetWxObjectPtr() : NULL));
 
     ((classname*)(var.IsValueKindOf(&classname::ms_classInfo) ?\
                   var.GetWxObjectPtr() : NULL));
 

+// Replacement for using wxDynamicCast on a wxVariantData object
+#define wxDynamicCastVariantData(data, classname) dynamic_cast<classname*>(data)
+

 extern wxVariant WXDLLIMPEXP_BASE wxNullVariant;
 
 #endif // wxUSE_VARIANT
 extern wxVariant WXDLLIMPEXP_BASE wxNullVariant;
 
 #endif // wxUSE_VARIANT

diff --git a/src/common/variant.cpp b/src/common/variant.cpp
index 8f3344671fd24303edd38004f34efaca964553bc..5120dc5554dcabfbcd0dc3d37e06b86817df8254 100644 (file)
--- a/src/common/variant.cpp
+++ b/src/common/variant.cpp
@@ -130,7 +130,6 @@ bool wxVariant::operator!= (const wxVariant& variant) const
     return (!(*this == variant));
 }
 
     return (!(*this == variant));
 }
 

-

 wxString wxVariant::MakeString() const
 {
     if (!IsNull())
 wxString wxVariant::MakeString() const
 {
     if (!IsNull())


@@ -177,6 +176,30 @@ void wxVariant::UnRef()
     }
 }
 
     }
 }
 

+bool wxVariant::Unshare()
+{
+    if ( m_data && m_data->GetRefCount() > 1 )
+    {
+        // note that ref is not going to be destroyed in this case...
+        const wxVariantData* ref = m_data;
+        UnRef();
+
+        // ... so we can still access it
+        m_data = ref->Clone();
+
+        wxASSERT_MSG( (m_data && m_data->GetRefCount() == 1),
+                  _T("wxVariant::AllocExclusive() failed.") );
+
+        if (!m_data || m_data->GetRefCount() != 1)
+            return false;
+        else
+            return true;
+    }
+    //else: data is null or ref count is 1, so we are exclusive owners of m_refData anyhow
+    else
+        return true;
+}
+

 
 // Returns a string representing the type of the variant,
 // e.g. "string", "bool", "list", "double", "long"
 
 // Returns a string representing the type of the variant,
 // e.g. "string", "bool", "list", "double", "long"


@@ -227,6 +250,8 @@ public:
     virtual bool Write(wxOutputStream &str) const;
 #endif // wxUSE_STREAMS
 
     virtual bool Write(wxOutputStream &str) const;
 #endif // wxUSE_STREAMS
 

+    wxVariantData* Clone() const { return new wxVariantDataLong(m_value); }
+

     virtual wxString GetType() const { return wxT("long"); }
 
 protected:
     virtual wxString GetType() const { return wxT("long"); }
 
 protected:


@@ -377,6 +402,7 @@ public:
 #endif // wxUSE_STREAMS
     virtual wxString GetType() const { return wxT("double"); }
 
 #endif // wxUSE_STREAMS
     virtual wxString GetType() const { return wxT("double"); }
 

+    wxVariantData* Clone() const { return new wxVariantDoubleData(m_value); }

 protected:
     double m_value;
 };
 protected:
     double m_value;
 };


@@ -514,6 +540,7 @@ public:
 #endif // wxUSE_STREAMS
     virtual wxString GetType() const { return wxT("bool"); }
 
 #endif // wxUSE_STREAMS
     virtual wxString GetType() const { return wxT("bool"); }
 

+    wxVariantData* Clone() const { return new wxVariantDataBool(m_value); }

 protected:
     bool m_value;
 };
 protected:
     bool m_value;
 };


@@ -651,6 +678,7 @@ public:
     virtual bool Write(wxOutputStream& str) const;
 #endif // wxUSE_STREAMS
     virtual wxString GetType() const { return wxT("char"); }
     virtual bool Write(wxOutputStream& str) const;
 #endif // wxUSE_STREAMS
     virtual wxString GetType() const { return wxT("char"); }

+    wxVariantData* Clone() const { return new wxVariantDataChar(m_value); }

 
 protected:
     wxUniChar m_value;
 
 protected:
     wxUniChar m_value;


@@ -802,6 +830,7 @@ public:
     virtual bool Write(wxOutputStream& str) const;
 #endif // wxUSE_STREAMS
     virtual wxString GetType() const { return wxT("string"); }
     virtual bool Write(wxOutputStream& str) const;
 #endif // wxUSE_STREAMS
     virtual wxString GetType() const { return wxT("string"); }

+    wxVariantData* Clone() const { return new wxVariantDataString(m_value); }

 
 protected:
     wxString m_value;
 
 protected:
     wxString m_value;


@@ -955,10 +984,10 @@ public:
 #endif
     virtual bool Read(wxString& str);
     virtual wxString GetType() const ;
 #endif
     virtual bool Read(wxString& str);
     virtual wxString GetType() const ;

-    virtual wxVariantData* Clone() { return new wxVariantDataWxObjectPtr; }
+    virtual wxVariantData* Clone() const { return new wxVariantDataWxObjectPtr(m_value); }

 
     virtual wxClassInfo* GetValueClassInfo();
 
     virtual wxClassInfo* GetValueClassInfo();

-    
+

 protected:
     wxObject* m_value;
 };
 protected:
     wxObject* m_value;
 };


@@ -975,13 +1004,13 @@ bool wxVariantDataWxObjectPtr::Eq(wxVariantData& data) const
 wxString wxVariantDataWxObjectPtr::GetType() const
 {
     wxString returnVal(wxT("wxObject*"));
 wxString wxVariantDataWxObjectPtr::GetType() const
 {
     wxString returnVal(wxT("wxObject*"));

-    
+

     if (m_value)
     {
         returnVal = m_value->GetClassInfo()->GetClassName();
         returnVal += wxT("*");
     }
     if (m_value)
     {
         returnVal = m_value->GetClassInfo()->GetClassName();
         returnVal += wxT("*");
     }

-    
+

     return returnVal;
 }
 
     return returnVal;
 }
 


@@ -1076,7 +1105,7 @@ public:
 #endif
     virtual bool Read(wxString& str);
     virtual wxString GetType() const { return wxT("void*"); }
 #endif
     virtual bool Read(wxString& str);
     virtual wxString GetType() const { return wxT("void*"); }

-    virtual wxVariantData* Clone() { return new wxVariantDataVoidPtr; }
+    virtual wxVariantData* Clone() const { return new wxVariantDataVoidPtr(m_value); }

 
 protected:
     void* m_value;
 
 protected:
     void* m_value;


@@ -1193,7 +1222,7 @@ public:
 #endif
     virtual bool Read(wxString& str);
     virtual wxString GetType() const { return wxT("datetime"); }
 #endif
     virtual bool Read(wxString& str);
     virtual wxString GetType() const { return wxT("datetime"); }

-    virtual wxVariantData* Clone() { return new wxVariantDataDateTime; }
+    virtual wxVariantData* Clone() const { return new wxVariantDataDateTime(m_value); }

 
 protected:
     wxDateTime m_value;
 
 protected:
     wxDateTime m_value;


@@ -1357,7 +1386,7 @@ public:
 #endif
     virtual bool Read(wxString& str);
     virtual wxString GetType() const { return wxT("arrstring"); }
 #endif
     virtual bool Read(wxString& str);
     virtual wxString GetType() const { return wxT("arrstring"); }

-    virtual wxVariantData* Clone() { return new wxVariantDataArrayString; }
+    virtual wxVariantData* Clone() const { return new wxVariantDataArrayString(m_value); }

 
 protected:
     wxArrayString m_value;
 
 protected:
     wxArrayString m_value;


@@ -1484,6 +1513,7 @@ public:
 
     void Clear();
 
 
     void Clear();
 

+    wxVariantData* Clone() const { return new wxVariantDataList(m_value); }

 protected:
     wxVariantList  m_value;
 };
 protected:
     wxVariantList  m_value;
 };