private void btnAddBaseLayer_Click(object sender, EventArgs e)
 {
     using (var picker = new ResourcePicker(_edSvc.CurrentConnection, ResourceTypes.LayerDefinition.ToString(), ResourcePickerMode.OpenResource))
     {
         if (picker.ShowDialog() == DialogResult.OK)
         {
             LastSelectedFolder.FolderId = picker.SelectedFolder;
             string        layerId = picker.ResourceID;
             IBaseMapGroup grp     = null;
             var           group   = GetSelectedTiledLayerItem() as BaseLayerGroupItem;
             if (group != null)
             {
                 grp = group.Tag;
             }
             else
             {
                 grp = _tsd.GetFirstGroup();
                 if (grp == null)
                 {
                     grp = _tsd.AddBaseLayerGroup(GenerateBaseGroupName(_tsd));
                 }
             }
             var bl = grp.AddLayer(GenerateBaseLayerName(layerId, _tsd), layerId);
             _tiledLayerModel.Invalidate();
             RestoreBaseLayerSelection(bl);
         }
     }
 }