diff --git a/examples/osgviewerWX/osgviewerWX.cpp b/examples/osgviewerWX/osgviewerWX.cpp
index 0a7ac616f..b9d34f4e3 100644
--- a/examples/osgviewerWX/osgviewerWX.cpp
+++ b/examples/osgviewerWX/osgviewerWX.cpp
@@ -106,6 +106,9 @@ void MainFrame::SetViewer(osgViewer::Viewer *viewer)
 
 void MainFrame::OnIdle(wxIdleEvent &event)
 {
+    if (!_viewer->isRealized())
+        return;
+
     _viewer->frame();
 
     event.RequestMore();
diff --git a/examples/osgviewerWX/osgviewerWX.h b/examples/osgviewerWX/osgviewerWX.h
index a79368c9e..db41d24a2 100644
--- a/examples/osgviewerWX/osgviewerWX.h
+++ b/examples/osgviewerWX/osgviewerWX.h
@@ -67,7 +67,7 @@ public:
     // not implemented yet...just use dummy implementation to get working.
     virtual bool valid() const { return true; }
     virtual bool realizeImplementation() { return true; }
-    virtual bool isRealizedImplementation() const  { return true; }
+    virtual bool isRealizedImplementation() const  { return _canvas->IsShownOnScreen(); }
     virtual void closeImplementation() {}
     virtual bool releaseContextImplementation() { return true; }