+ /**
+ Draw a title bar button in the given state.
+
+ This function is currently only available under MSW and OS X (and only
+ for wxTITLEBAR_BUTTON_CLOSE under the latter), its best replacement for
+ the other platforms is to use wxArtProvider to retrieve the bitmaps for
+ @c wxART_HELP and @c wxART_CLOSE (but not any other title bar buttons
+ and not for any state but normal, i.e. not pressed and not current one).
+
+ The presence of this function is indicated by @c
+ wxHAS_DRAW_TITLE_BAR_BITMAP symbol being defined.
+
+ Also notice that PNG handler must be enabled using wxImage::AddHandler()
+ to use this function under OS X currently as the bitmaps are embedded
+ in the library itself in PNG format.
+
+ @since 2.9.1
+ */
+ virtual void DrawTitleBarBitmap(wxWindow *win,
+ wxDC& dc,
+ const wxRect& rect,
+ wxTitleBarButton button,
+ int flags = 0) = 0;
+