That work around works, but it's a great shame the method we posted above doesn't work.

Hi,

Looking at your code, your problem seems very similar to this forum post.

http://forums.infragistics.com/forums/t/29187.aspx

This issue has been logged internally here and is being investigated.  If you would like to contact dev support, the bug number is 19864.

In the meantime, you could try the work around mentioned in the other post.  Simply try adding the nodes to the data tree before adding children.  That seems to work ok.

regards,

David Young

        private void PopulateTree()
        {

            // Get the data
            List<CompanyEntity> companyList = this.BuildCompanyList();
            List<CustomerEntity> customerList = this.BuildCustomerList();

            List<DataTreeNode> nodeList = new List<DataTreeNode>();
            foreach (CompanyEntity company in companyList)
            {

                // Build the company node
                DataTreeNode companyNode = new DataTreeNode();
                nodeList.Add(companyNode);

                companyNode.Key = company.CompanyId.ToString();
                companyNode.Value = company.CompanyId.ToString();
                companyNode.Text = company.Description;

                // Build the customer node list
                List<CustomerEntity> companyCustomerList = customerList.FindAll(
                    delegate(CustomerEntity p)
                    {
                        return p.CompanyId == company.CompanyId;
                    }
                );

                companyCustomerList.Sort(
                    delegate(CustomerEntity p1, CustomerEntity p2)
                    {
                        return p1.Name.CompareTo(p2.Name);
                    }
                );

                List<DataTreeNode> customerCollection = new List<DataTreeNode>();
                foreach (CustomerEntity customer in companyCustomerList)
                {

                    DataTreeNode customerNode = new DataTreeNode();
                    customerNode.Key = customer.CustomerId.ToString();
                    customerNode.Value = customer.CustomerId.ToString();
                    customerNode.Text = customer.Name;
                   
                    customerCollection.Add(customerNode);

                }

                companyNode.Nodes.AddRange(customerCollection.ToArray());

            }

            // Display the data
            this.WebDataTree1.Nodes.AddRange(nodeList.ToArray());

        }