diff --git a/include/osgViewer/ViewerEventHandlers b/include/osgViewer/ViewerEventHandlers
index 0d8b9090f..117fe7dc7 100644
--- a/include/osgViewer/ViewerEventHandlers
+++ b/include/osgViewer/ViewerEventHandlers
@@ -533,7 +533,8 @@ protected:
 
     virtual ~InteractiveImageHandler() {}
 
-    InteractiveImageHandler() {}
+    InteractiveImageHandler():
+        _fullscreen(false) {}
 
     InteractiveImageHandler(const InteractiveImageHandler&,const osg::CopyOp& = osg::CopyOp::SHALLOW_COPY):
         osg::Object(), osg::Callback(), osgGA::GUIEventHandler(), osg::DrawableCullCallback(), _fullscreen(false) {}