I'm going to guess that you're using DefaultTreeModel. There are 2 constructors:
public DefaultTreeModel(ValueEncoder<T> encoder, TreeModelAdapter<T> adapter, T root) and public DefaultTreeModel(ValueEncoder<T> encoder, TreeModelAdapter<T> adapter, List<T> roots) If your tree is null, then you have no roots. Don't pass null to the first constructor because this will create a list with 1 null element in it (which is probably causing your NPE). Instead, pass Collections.emptyList() (or possibly null) to the second constructor. -- View this message in context: http://tapestry.1045711.n5.nabble.com/NPE-in-Tree-when-I-dont-have-any-data-tp5720289p5720296.html Sent from the Tapestry - User mailing list archive at Nabble.com. --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tapestry.apache.org For additional commands, e-mail: users-h...@tapestry.apache.org
