private void mnu_addSourceProject(object sender, EventArgs e)
        {
            TreeViewWix tv = this.TreeView as TreeViewWix;
            Form        f  = null;

            if (this.TreeView != null)
            {
                f = this.TreeView.FindForm();
            }
            OpenFileDialog dlg = new OpenFileDialog();

            dlg.Filter = "Limnor Project|*.lrproj";
            dlg.Title  = "Select Limnor Project File";
            if (dlg.ShowDialog(f) == DialogResult.OK)
            {
                Folder.AddProject(dlg.FileName);
                if (tv != null)
                {
                    tv.OnPropertyValueChanged();
                }
                UserControlSetupProperties ucp = getHolder();
                if (ucp != null)
                {
                    ucp.OnSelectTreeNode(this);
                }
            }
        }