Folder model = TestData.getTreeModel();
TreeStore<ModelData> store = new TreeStore<ModelData>();
store.add(model.getChildren(), true);
RowNumberer numberer = new RowNumberer();
ColumnConfig name = new ColumnConfig("name", "Name", 100);
name.setRenderer(new TreeGridCellRenderer<ModelData>());
ColumnConfig date = new ColumnConfig("author", "Author", 100);