code: public void onFolderClick(FolderClickEvent event) {
  		try {
  
  			if (isIconTargetClicked()) {
  				onIconClick(event.getFolder());
  			} else {
  				if (event.getFolder() instanceof LayerTreeTreeNode) {
  					mapModel.selectLayer(((LayerTreeTreeNode) event.getFolder()).getLayer());
  				} else {
  					mapModel.selectLayer(null);
  				}
  			}
  		} catch (Exception e) { // NOSONAR
  			Log.logError(e.getMessage());
  			// some other unusable element
  		}
  	}
docs: When the user clicks on a folder nothing gets selected.
  
  @param event
  event