-IMPLEMENT_ABSTRACT_CLASS(wxSizerItem, wxObject)
-IMPLEMENT_ABSTRACT_CLASS(wxSizer, wxObject)
-IMPLEMENT_ABSTRACT_CLASS(wxGridSizer, wxSizer)
-IMPLEMENT_ABSTRACT_CLASS(wxFlexGridSizer, wxGridSizer)
-IMPLEMENT_ABSTRACT_CLASS(wxBoxSizer, wxSizer)
+IMPLEMENT_CLASS(wxSizerItem, wxObject)
+IMPLEMENT_CLASS(wxSizer, wxObject)
+IMPLEMENT_CLASS(wxGridSizer, wxSizer)
+IMPLEMENT_CLASS(wxFlexGridSizer, wxGridSizer)
+IMPLEMENT_CLASS(wxBoxSizer, wxSizer)