avoid code duplication by using helper functions

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@45428 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/gtk/listbox.h

@@ -7,8 +7,11 @@
 // Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////
 
-#ifndef __GTKLISTBOXH__
-#define __GTKLISTBOXH__
+#ifndef _WX_GTK_LISTBOX_H_
+#define _WX_GTK_LISTBOX_H_
+
+struct _GtkTreeEntry;
+struct _GtkTreeIter;
 
 //-----------------------------------------------------------------------------
 // wxListBox
@@ -94,7 +97,7 @@ public:
 
     bool       m_blockEvent;
 
-    struct _GtkTreeEntry* GtkGetEntry(int pos) const;
+    struct _GtkTreeEntry* GtkGetEntry(unsigned pos) const;
     void GtkInsertItems(const wxArrayString& items,
                         void** clientData, unsigned int pos);
     void GtkDeselectAll();
@@ -116,10 +119,19 @@ protected:
     virtual wxClientData* DoGetItemClientObject(unsigned int n) const;
     virtual int DoListHitTest(const wxPoint& point) const;
 
+    // get the iterator for the given index, returns false if invalid
+    bool GtkGetIteratorFor(unsigned pos, _GtkTreeIter *iter) const;
+
+    // get the index for the given iterator, return wxNOT_FOUND on failure
+    int GtkGetIndexFor(_GtkTreeIter& iter) const;
+
+    // set the specified item
+    void GtkSetItem(_GtkTreeIter& iter, const _GtkTreeEntry *entry);
+
 private:
     void Init(); //common construction
 
     DECLARE_DYNAMIC_CLASS(wxListBox)
 };
 
-#endif // __GTKLISTBOXH__
+#endif // _WX_GTK_LISTBOX_H_