diff --git a/screening/source/java/ch/systemsx/cisd/openbis/plugin/screening/client/web/client/application/detailviewers/ChannelWidgetWithListener.java b/screening/source/java/ch/systemsx/cisd/openbis/plugin/screening/client/web/client/application/detailviewers/ChannelWidgetWithListener.java
index 39cab20c55d23919f5e1152a7bb17d79d3082c20..91a80986e52aa5c344ab2e99b9cb8a1443bf745e 100644
--- a/screening/source/java/ch/systemsx/cisd/openbis/plugin/screening/client/web/client/application/detailviewers/ChannelWidgetWithListener.java
+++ b/screening/source/java/ch/systemsx/cisd/openbis/plugin/screening/client/web/client/application/detailviewers/ChannelWidgetWithListener.java
@@ -34,12 +34,13 @@ import ch.systemsx.cisd.openbis.plugin.screening.client.web.client.application.u
  */
 public class ChannelWidgetWithListener
 {
-    final LayoutContainer container = new LayoutContainer();
+    final private LayoutContainer container;
 
-    final IChanneledViewerFactory viewerFactory;
+    final private IChanneledViewerFactory viewerFactory;
 
     public ChannelWidgetWithListener(final IChanneledViewerFactory viewerFactory)
     {
+        this.container = new LayoutContainer();
         this.viewerFactory = viewerFactory;
     }