Refactor: replace wxTreeItemId and wxDataViewItem with new wxItemId<>.

Add wxItemId<> template which can be used to identify items in different
{tree,list}-like controls, including wxDataViewCtrl (where it replaces, in
backwards compatible way, wxDataViewItem), wxTreeCtrl (where it replaces
wxTreeItemId) and the upcoming wxTreeListCtrl.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@68812 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

Makefile.in

@@ -3905,6 +3905,7 @@ COND_USE_GUI_1_ALL_GUI_HEADERS =  \
 	wx/helphtml.h \
 	wx/icon.h \
 	wx/infobar.h \
+	wx/itemid.h \
 	wx/layout.h \
 	wx/listbox.h \
 	wx/mdi.h \

build/bakefiles/files.bkl

@@ -879,6 +879,7 @@ IMPORTANT: please read docs/tech/tn0016.txt before modifying this file!
     wx/helphtml.h
     wx/icon.h
     wx/infobar.h
+    wx/itemid.h
     wx/layout.h
     wx/listbox.h
     wx/mdi.h

build/msw/wx_core.dsp

@@ -6444,6 +6444,10 @@ SOURCE=..\..\include\wx\infobar.h
 # End Source File
 # Begin Source File
 
+SOURCE=..\..\include\wx\itemid.h
+# End Source File
+# Begin Source File
+
 SOURCE=..\..\include\wx\joystick.h
 # End Source File
 # Begin Source File

build/msw/wx_vc7_core.vcproj

@@ -5408,6 +5408,9 @@
 			<File
 				RelativePath="..\..\include\wx\infobar.h">
 			</File>
+			<File
+				RelativePath="..\..\include\wx\itemid.h">
+			</File>
 			<File
 				RelativePath="..\..\include\wx\joystick.h">
 			</File>

build/msw/wx_vc8_core.vcproj

@@ -7231,6 +7231,10 @@
 				RelativePath="..\..\include\wx\infobar.h"
 				>
 			</File>
+			<File
+				RelativePath="..\..\include\wx\itemid.h"
+				>
+			</File>
 			<File
 				RelativePath="..\..\include\wx\joystick.h"
 				>

build/msw/wx_vc9_core.vcproj

@@ -7227,6 +7227,10 @@
 				RelativePath="..\..\include\wx\infobar.h"
 				>
 			</File>
+			<File
+				RelativePath="..\..\include\wx\itemid.h"
+				>
+			</File>
 			<File
 				RelativePath="..\..\include\wx\joystick.h"
 				>

include/wx/dataview.h

@@ -21,6 +21,7 @@
 #include "wx/variant.h"
 #include "wx/dynarray.h"
 #include "wx/icon.h"
+#include "wx/itemid.h"
 #include "wx/weakref.h"
 #include "wx/vector.h"
 #include "wx/dataobj.h"
@@ -45,7 +46,6 @@ class WXDLLIMPEXP_FWD_CORE wxImageList;
 // wxDataViewCtrl globals
 // ----------------------------------------------------------------------------
 
-class WXDLLIMPEXP_FWD_ADV wxDataViewItem;
 class WXDLLIMPEXP_FWD_ADV wxDataViewModel;
 class WXDLLIMPEXP_FWD_ADV wxDataViewCtrl;
 class WXDLLIMPEXP_FWD_ADV wxDataViewColumn;
@@ -79,34 +79,14 @@ extern WXDLLIMPEXP_DATA_ADV(const char) wxDataViewCtrlNameStr[];
 // wxDataViewItem
 // ---------------------------------------------------------
 
-class WXDLLIMPEXP_ADV wxDataViewItem
+// Make it a class and not a typedef to allow forward declaring it.
+class wxDataViewItem : public wxItemId<void*>
 {
 public:
-    wxDataViewItem() : m_id(NULL) {}
+    wxDataViewItem() : wxItemId<void*>() { }
-    wxDataViewItem(const wxDataViewItem &item) : m_id(item.m_id) {}
+    wxEXPLICIT wxDataViewItem(void* pItem) : wxItemId<void*>(pItem) { }
-
-    wxEXPLICIT wxDataViewItem(void* id) : m_id(id) {}
-
-    bool IsOk() const                  { return m_id != NULL; }
-    void* GetID() const                { return m_id; }
-    operator const void* () const      { return m_id; }
-
-private:
-    void* m_id;
 };
 
-inline
-bool operator==(const wxDataViewItem& left, const wxDataViewItem& right)
-{
-    return left.GetID() == right.GetID();
-}
-
-inline
-bool operator!=(const wxDataViewItem& left, const wxDataViewItem& right)
-{
-    return !(left == right);
-}
-
 WX_DEFINE_ARRAY(wxDataViewItem, wxDataViewItemArray);
 
 // ---------------------------------------------------------

include/wx/itemid.h

@@ -0,0 +1,59 @@
+///////////////////////////////////////////////////////////////////////////////
+// Name:        wx/itemid.h
+// Purpose:     wxItemId class declaration.
+// Author:      Vadim Zeitlin
+// Created:     2011-08-17
+// RCS-ID:      $Id: wxhead.h,v 1.12 2010-04-22 12:44:51 zeitlin Exp $
+// Copyright:   (c) 2011 Vadim Zeitlin <vadim@wxwidgets.org>
+// Licence:     wxWindows licence
+///////////////////////////////////////////////////////////////////////////////
+
+#ifndef _WX_ITEMID_H_
+#define _WX_ITEMID_H_
+
+// ----------------------------------------------------------------------------
+// wxItemId: an opaque item identifier used with wx{Tree,TreeList,DataView}Ctrl.
+// ----------------------------------------------------------------------------
+
+// The template argument T is typically a pointer to some opaque type. While
+// wxTreeItemId and wxDataViewItem use a pointer to void, this is dangerous and
+// not recommended for the new item id classes.
+template <typename T>
+class wxItemId
+{
+public:
+    typedef T Type;
+
+    // This ctor is implicit which is fine for non-void* types, but if you use
+    // this class with void* you're strongly advised to make the derived class
+    // ctor explicit as implicitly converting from any pointer is simply too
+    // dangerous.
+    wxItemId(Type item = NULL) : m_pItem(item) { }
+
+    // Default copy ctor, assignment operator and dtor are ok.
+
+    bool IsOk() const { return m_pItem != NULL; }
+    Type GetID() const { return m_pItem; }
+    operator const Type() const { return m_pItem; }
+
+    void Unset() { m_pItem = NULL; }
+
+    // This field is public *only* for compatibility with the old wxTreeItemId
+    // implementation and must not be used in any new code.
+//private:
+    Type m_pItem;
+};
+
+template <typename T>
+bool operator==(const wxItemId<T>& left, const wxItemId<T>& right)
+{
+    return left.GetID() == right.GetID();
+}
+
+template <typename T>
+bool operator!=(const wxItemId<T>& left, const wxItemId<T>& right)
+{
+    return !(left == right);
+}
+
+#endif // _WX_ITEMID_H_

include/wx/treebase.h

@@ -23,6 +23,7 @@
 #include "wx/window.h"  // for wxClientData
 #include "wx/event.h"
 #include "wx/dynarray.h"
+#include "wx/itemid.h"
 
 #if WXWIN_COMPATIBILITY_2_6
 
@@ -38,53 +39,19 @@ enum
 #endif // WXWIN_COMPATIBILITY_2_6
 
 // ----------------------------------------------------------------------------
-// wxTreeItemId identifies an element of the tree. In this implementation, it's
+// wxTreeItemId identifies an element of the tree. It's opaque for the
-// just a trivial wrapper around Win32 HTREEITEM or a pointer to some private
+// application and the only method which can be used by user code is IsOk().
-// data structure in the generic version. It's opaque for the application and
-// the only method which can be used by user code is IsOk().
 // ----------------------------------------------------------------------------
 
-// Using this typedef removes an ambiguity when calling Remove()
+// This is a class and not a typedef because existing code may forward declare
-typedef void *wxTreeItemIdValue;
+// wxTreeItemId as a class and we don't want to break it without good reason.
-
+class wxTreeItemId : public wxItemId<void*>
-class WXDLLIMPEXP_CORE wxTreeItemId
 {
-    friend bool operator==(const wxTreeItemId&, const wxTreeItemId&);
 public:
-    // ctors
+    wxTreeItemId() : wxItemId<void*>() { }
-        // 0 is invalid value for HTREEITEM
+    wxTreeItemId(void* pItem) : wxItemId<void*>(pItem) { }
-    wxTreeItemId() { m_pItem = 0; }
-
-        // construct wxTreeItemId from the native item id
-    wxTreeItemId(void *pItem) { m_pItem = pItem; }
-
-        // default copy ctor/assignment operator are ok for us
-
-    // accessors
-        // is this a valid tree item?
-    bool IsOk() const { return m_pItem != 0; }
-        // return true if this item is not valid
-    bool operator!() const { return !IsOk(); }
-
-    // operations
-        // invalidate the item
-    void Unset() { m_pItem = 0; }
-
-    operator bool() const { return IsOk(); }
-
-    wxTreeItemIdValue m_pItem;
 };
 
-inline bool operator==(const wxTreeItemId& i1, const wxTreeItemId& i2)
-{
-    return i1.m_pItem == i2.m_pItem;
-}
-
-inline bool operator!=(const wxTreeItemId& i1, const wxTreeItemId& i2)
-{
-    return i1.m_pItem != i2.m_pItem;
-}
-
 // ----------------------------------------------------------------------------
 // wxTreeItemData is some (arbitrary) user class associated with some item. The
 // main advantage of having this class (compared to old untyped interface) is
@@ -119,10 +86,12 @@ protected:
     wxTreeItemId m_pItem;
 };
 
+typedef void *wxTreeItemIdValue;
+
 WX_DEFINE_EXPORTED_ARRAY_PTR(wxTreeItemIdValue, wxArrayTreeItemIdsBase);
 
 // this is a wrapper around the array class defined above which allow to wok
-// with vaue of natural wxTreeItemId type instead of using wxTreeItemIdValue
+// with values of natural wxTreeItemId type instead of using wxTreeItemIdValue
 // and does it without any loss of efficiency
 class WXDLLIMPEXP_CORE wxArrayTreeItemIds : public wxArrayTreeItemIdsBase
 {