Custom tree node and DefaultTreeModel

Question

Hello,
I would like to know if it's possible to use the following custom tree node with the DefaultTreeModel:
class MyTreeNode extends DefaultMutableTreeNode{
  private String _argument = null;
  public MyTreeNode(){}
  public MyTreeNode(Object node, String argument){
     super(node);
      _argument = argument;
}I have tried it and it's not working but I think in theory it should work. Please correct me if I'm wrong.
The problem is that the tree won't display or insert the custom node when the insertNodeAt(...) method of
the DefaultTreeModel is called. I also tried using a custom tree listener and calling the .reload() method directly.
Any help will be very appreciated.
Thanks in advanced.

Answer 1

Are you sure it's not being inserted into the model,
and just not being displayed?
Are you calling nodesWereInserted() after your
insertion?Thanks for your reply.
I've modified my app. so that the following method will populate the tree for testing only:
  public void populateTree()
    MyTreeNode root = new MyTreeNode("Root Node", "test");
    DefaultTreeModel treeModel = new DefaultTreeModel(root);
    JTree tree = new JTree(treeModel);
    tree.setEditable(true);
    tree.getSelectionModel().setSelectionMode(TreeSelectionModel.SINGLE_TREE_SELECTION);
    tree.setShowsRootHandles(true);
    JScrollPane scrollPane = new JScrollPane(tree);
    setLayout(new GridLayout(1,0));
    add(scrollPane);
    int childIdx[] = {0,1};
    String p1Name = new String("Parent 1");
    String p2Name = new String("Parent 2");
    String c1Name = new String("Child 1");
    String c2Name = new String("Child 2");
    MyTreeNode p1 = new MyTreeNode(p1Name, "test");
    MyTreeNode p2 = new MyTreeNode(p2Name, "test");
    MyTreeNode c1 = new MyTreeNode(c1Name, "test");
    MyTreeNode c2 = new MyTreeNode(c2Name, "test");
    treeModel.insertNodeInto(p1, root, 0);
    treeModel.insertNodeInto(p2, root, 1);
    treeModel.nodesWereInserted(root, childIdx);
    treeModel.insertNodeInto(c1, p1, 0);
    treeModel.insertNodeInto(c2, p1, 1);
    treeModel.nodesWereInserted(p1, childIdx);
    treeModel.reload();
}And the result is that the "Root Node" will be displayed with "Parent1" and "Parent2" but "Parent1" won't have any children. Furthermore, if I try to remove "Parent1" using:
treeModel.removeNodeFromParent(p1);I will get an exception saying that node p1 has no parent, which suggests that the parent/child relation
is not being assigned by the model, even though the nodes (p1, p2) are displayed in the tree showing "Root node" as the parent. This is very strange.
Please help.