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TabPanel update ignores TabItemConfig close
calling TabPanel.update(Widget,new TabItemConfig(String text,Boolean close) updates the text but not the close.
I believe the culprit to be in TabPanelBaseAppearance updateItem(XElement item, TabItemConfig config), config.isClosable() isn't used unlike the insert method.
Found in GXT 3.0.1
Thanks for the report! I have opened a bug in our bug tracker.
This has been fixed in SVN, and will be available in the next release. The fix was to modify the TabPanelBaseAppearance so that the update item method also toggled the close class name, as the insert method did.