1. GetNextChild() bug fixed in generic version

2. GetChildrenCount(bool recursive) added to all versions, implemented
   only in the generic one so far
3. Sample slightly modified to show new function


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@996 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/generic/treectrl.h

@@ -268,6 +268,13 @@ public:
         // is this item currently selected (the same as has focus)?
     bool IsSelected(const wxTreeItemId& item) const;
 
+    // number of children
+    // ------------------
+
+        // if 'recursively' is FALSE, only immediate children count, otherwise
+        // the returned number is the number of all items in this branch
+    size_t GetChildrenCount(const wxTreeItemId& item, bool recursively = TRUE);
+
     // navigation
     // ----------