2 files changed, 13 insertions, 0 deletions
diff --git a/client/src/com/vaadin/client/ui/VCustomLayout.java b/client/src/com/vaadin/client/ui/VCustomLayout.java
index 5f8a8197d0..0ee50fe0dd 100644
--- a/client/src/com/vaadin/client/ui/VCustomLayout.java
+++ b/client/src/com/vaadin/client/ui/VCustomLayout.java
@@ -305,6 +305,10 @@ public class VCustomLayout extends ComplexPanel {
     /** Update caption for given widget */
     public void updateCaption(ComponentConnector paintable) {
         Widget widget = paintable.getWidget();
+        if (widget.getParent() != this) {
+            // Widget has not been added because the location was not found
+            return;
+        }
         VCaptionWrapper wrapper = childWidgetToCaptionWrapper.get(widget);
         if (VCaption.isNeeded(paintable.getState())) {
             if (wrapper == null) {
diff --git a/client/src/com/vaadin/client/ui/customlayout/CustomLayoutConnector.java b/client/src/com/vaadin/client/ui/customlayout/CustomLayoutConnector.java
index cde1f1af0f..abbb0ef60b 100644
--- a/client/src/com/vaadin/client/ui/customlayout/CustomLayoutConnector.java
+++ b/client/src/com/vaadin/client/ui/customlayout/CustomLayoutConnector.java
@@ -15,6 +15,8 @@
  */
 package com.vaadin.client.ui.customlayout;
 
+import java.util.logging.Logger;
+
 import com.google.gwt.user.client.DOM;
 import com.google.gwt.user.client.ui.Widget;
 import com.vaadin.client.ApplicationConnection;
@@ -111,6 +113,9 @@ public class CustomLayoutConnector extends AbstractLayoutConnector implements
                 getWidget().setWidget(child.getWidget(), location);
             } catch (final IllegalArgumentException e) {
                 // If no location is found, this component is not visible
+                getLogger().warning(
+                        "Child not rendered as no slot with id '" + location
+                                + "' has been defined");
             }
         }
         for (ComponentConnector oldChild : event.getOldChildren()) {
@@ -147,4 +152,8 @@ public class CustomLayoutConnector extends AbstractLayoutConnector implements
         // Not interested in anything from the UIDL - just implementing the
         // interface to avoid some warning (#8688)
     }
+
+    private static Logger getLogger() {
+        return Logger.getLogger(CustomLayoutConnector.class.getName());
+    }
 }