Load a new Tree when a VisualItem is clicked in prefuse?

[Doomclip]

I would like to load a new Tree structure from an xml after I clicked on a prefuse VisualItem (NodeItem).I have tried to call clear on the tree that I have currently loaded and then reuse that tree to load a new one and visualize it. I keep getting an error when I try to load the tree : \[code\]08.05.2012 12:57:45 prefuse.Display$InputEventCapturer fireItemClickedWARNING: Exception thrown by Control: java.lang.ArrayIndexOutOfBoundsException: -1java.lang.ArrayIndexOutOfBoundsException: -1 at java.util.ArrayList.get(ArrayList.java:324) at prefuse.data.Table.getColumn(Table.java:457) at prefuse.data.Table.setString(Table.java:1427) at prefuse.data.tuple.TableTuple.setString(TableTuple.java:455) at loader.TreeLoader.downLevel(TreeLoader.java:322) at visualizations.PrefuseTreeVisual$2.itemClicked(PrefuseTreeVisual.java:302) at prefuse.Display$InputEventCapturer.fireItemClicked(Display.java:1738) at prefuse.Display$InputEventCapturer.mouseClicked(Display.java:1590) at java.awt.AWTEventMulticaster.mouseClicked(AWTEventMulticaster.java:252) at java.awt.Component.processMouseEvent(Component.java:6292) at javax.swing.JComponent.processMouseEvent(JComponent.java:3267) at java.awt.Component.processEvent(Component.java:6054) at java.awt.Container.processEvent(Container.java:2041) at java.awt.Component.dispatchEventImpl(Component.java:4652) at java.awt.Container.dispatchEventImpl(Container.java:2099) at java.awt.Component.dispatchEvent(Component.java:4482) at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4577) at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4247) at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4168) at java.awt.Container.dispatchEventImpl(Container.java:2085) at java.awt.Window.dispatchEventImpl(Window.java:2478) at java.awt.Component.dispatchEvent(Component.java:4482) at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:644) at java.awt.EventQueue.access$000(EventQueue.java:85) at java.awt.EventQueue$1.run(EventQueue.java:603) at java.awt.EventQueue$1.run(EventQueue.java:601) at java.security.AccessController.doPrivileged(Native Method) at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87) at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:98) at java.awt.EventQueue$2.run(EventQueue.java:617) at java.awt.EventQueue$2.run(EventQueue.java:615) at java.security.AccessController.doPrivileged(Native Method) at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87) at java.awt.EventQueue.dispatchEvent(EventQueue.java:614) at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269) at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184) at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161) at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)\[/code\]Is there any way to do this? Thanks in advance !