Add support for wxRibbonBar and related controls to XRC.

Add wxRibbonXmlHandler and an example of using it to the xrc sample.

Closes #12058.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@72729 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

samples/xrc/xrcdemo.cpp

@@ -38,6 +38,10 @@
 
 #include "wx/xrc/xmlres.h"          // XRC XML resources
 
+#if wxUSE_RIBBON
+    #include "wx/xrc/xh_ribbon.h"
+#endif // wxUSE_RIBBON
+
 #include "wx/cshelp.h"              // wxSimpleHelpProvider for helptext
 
 #include "myframe.h"
@@ -78,6 +82,10 @@ bool MyApp::OnInit()
     // wxXRC docs for details.
     wxXmlResource::Get()->InitAllHandlers();
 
+#if wxUSE_RIBBON
+    wxXmlResource::Get()->AddHandler(new wxRibbonXmlHandler);
+#endif
+
     // Load all of the XRC files that will be used. You can put everything
     // into one giant XRC file if you wanted, but then they become more
     // diffcult to manage, and harder to reuse in later projects.