}
public void treeStructureChanged(TreeModelEvent e) {
}
});
treeCategories.setCellRenderer(new CategoryTreeCellRenderer());
treeCategories.setDragEnabled(true);
treeCategories.setDropMode(ON);
treeCategories.setTransferHandler(new TreeDragAndDropHandler());
treeCategories.getSelectionModel().setSelectionMode(CONTIGUOUS_TREE_SELECTION);