In my xaml I have
        <ControlTemplate x:Name="controlTreeItemTemplate" TargetType="Controls1:XamTreeItem">
            <TextBox x:Name="ModifyText" LostFocus="ModifyTextLostFocus" Loaded="ModifyTextLoaded"></TextBox>
        </ControlTemplate>

in code behind

        private ControlTemplate _Template;
        // Change the template to a textbox to allow the new report name to be
        // entered directly into the selected tree item.
        private void MenuRenameClick(object sender, EventArgs e)
        {
            //ReportTreeViewModel.MenuRename();
            _Template = _RenameNode.Template;
            _RenameNode = ReportTreeViewModel.SelectedNode;
            _RenameNode.Template = controlTreeItemTemplate;
        }

        // Rename Menu - Default the textbox to the current report name.
        private void ModifyTextLoaded(object sender, RoutedEventArgs e)
        {
            var modifytext = ((TextBox)sender);
            modifytext.Text = _RenameNode.Header.ToString();
            modifytext.Focus();
            modifytext.MaxLength = ReportGroupTreeViewHelper.IsReportNode(_RenameNode) ? 50 : 200;
        }

        // Rename Menu
        private void ModifyTextLostFocus(object sender, RoutedEventArgs e)
        {
           // _RenameNode.Template = null;
            _RenameNode.Template = _Template;
            var tb = (TextBox)sender;
            ReportTreeViewModel.MenuRename();
        }

when I am trying to set template back its throwing error and when I am setting template to null in ModifyTextLostFocus the node is disappearing.

any help will be appreciated.

Thanks