optimize FindItem(data) performance (closes #9870)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@60362 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/msw/listctrl.h

@@ -14,8 +14,10 @@
 
 #include "wx/textctrl.h"
 #include "wx/dynarray.h"
+#include "wx/vector.h"
 
 class WXDLLIMPEXP_FWD_CORE wxImageList;
+class wxMSWListItemData;
 
 // define this symbol to indicate the availability of SetColumnsOrder() and
 // related functions
@@ -400,6 +402,9 @@ protected:
     // free memory taken by all internal data
     void FreeAllInternalData();
 
+    // get the internal data object for this item (may return NULL)
+    wxMSWListItemData *MSWGetItemData(long item) const;
+
     // get the item attribute, either by quering it for virtual control, or by
     // returning the one previously set using setter methods for a normal one
     wxListItemAttr *DoGetItemColumnAttr(long item, long column) const;
@@ -417,10 +422,9 @@ protected:
                                     // keep track of inserted/deleted columns
     long              m_count;      // Keep track of item count to save calls to
                                     // ListView_GetItemCount
-    bool              m_ignoreChangeMessages;
 
-    // true if we have any internal data (user data & attributes)
-    bool m_AnyInternalData;
+    // all wxMSWListItemData objects we use
+    wxVector<wxMSWListItemData *> m_internalData;
 
     // true if we have any items with custom attributes
     bool m_hasAnyAttr;