root.add(cwdFilesDir); cwdFilesDir.add(vcwdFilesDir);
model = new DefaultTreeModel(root); // a simple tree data model that uses TreeNodes
GVarsTree = new JTree(model); // JTree displays the set of hierarchical data of model
GVarsTree.setFont(GlobalValues.guifont);
// single selection
int mode = TreeSelectionModel.SINGLE_TREE_SELECTION;
GVarsTree.getSelectionModel().setSelectionMode(mode);