Select multiple nodes in a JTree a right click

Question

Hi all,
I've a JTree and I'd like to allow the user select some nodes (one or more) right click and than show a popupMenu.
This behavior seems not to be easy, because if I select a single node (right clicking on it) the node does not appear selected ; I need to select it left clicking and than everything works fine.
I read some posts found in the forum and the solution seems to be :
- attach a mouseListener to the JTree
- get the TreePath of the node selected
- force the selection on the node with setSelectionPath(TreePath)
This works fine if you need to select only one node, cause if you have to select more, you simply cannot.
I wonder a so obvious behavior is so hard to achieve.
I hope somebody out there had made the magic.
Any help would be appreciated.
Flavio Palumbo

Answer 1

Hi Darryl,
I wrote the test case below.
Using the methods you suggested it works almost fine.
The only behavior not desired is when you select a range (shift or control), release the key an than right click ; in this case remains selected the only node you clicked on ; to select the range clicking with the right button, you have to keep pressed the key.
Any hint would be appreciated.
Flavio
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import javax.swing.JFrame;
import javax.swing.JMenuItem;
import javax.swing.JPopupMenu;
import javax.swing.JTree;
import javax.swing.SwingUtilities;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.DefaultTreeModel;
import javax.swing.tree.TreePath;
public class TestTree {
    JTree jtr = null;
    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                new TestTree();
    public TestTree() {
        JFrame jf = new JFrame();
        jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        try {
            javax.swing.UIManager.setLookAndFeel(javax.swing.UIManager.getSystemLookAndFeelClassName());
            javax.swing.SwingUtilities.updateComponentTreeUI(jf);
        } catch (Throwable e) {
        jf.setPreferredSize(new java.awt.Dimension(200, 560));
        javax.swing.JScrollPane js = new javax.swing.JScrollPane();
        DefaultMutableTreeNode root = new DefaultMutableTreeNode("root");
        jtr = new JTree(root);
        jtr.addMouseListener(new TestTreeML());
        js.setViewportView(jtr);
        jf.getContentPane().add(js);
        for (int i = 0; i < 20; i++) {
            DefaultMutableTreeNode nodoFiglio = new DefaultMutableTreeNode("nodo" + i);
            ((DefaultTreeModel) jtr.getModel()).insertNodeInto(nodoFiglio, root, root.getChildCount());
        jf.pack();
        jf.setVisible(true);
    public class TestTreeML extends MouseAdapter {
        @Override
        public void mousePressed(MouseEvent e) {
        @Override
        public void mouseClicked(MouseEvent e) {
            try {
                if (!e.getSource().equals(jtr)) {
                    return;
                TreePath tpSel = jtr.getPathForLocation(e.getX(), e.getY());
                if (tpSel == null) {
                    return;
                int i = 0;
                final DefaultMutableTreeNode node = (DefaultMutableTreeNode) tpSel.getLastPathComponent();
                TreePath[] tpExisting = null;
                if (e.isControlDown() || e.isShiftDown()) {
                    System.out.println("control/shift");
                    TreePath[] tpEx = jtr.getSelectionPaths();
                    tpExisting = java.util.Arrays.copyOfRange(tpEx, 0, tpEx.length + 1);
                    i = tpEx.length;
                } else {
                    tpExisting = new TreePath[1];
                tpExisting[i] = tpSel;
                jtr.setSelectionPaths(tpExisting);
                if (e.getClickCount() == 2) {
                    System.out.println("double click on " + node.getUserObject());
                if (javax.swing.SwingUtilities.isRightMouseButton(e)) {
                    if (!e.isControlDown()) {
                        jtr.setSelectionPath(tpSel);
                    JPopupMenu menu = new JPopupMenu();
                    JMenuItem it0 = new JMenuItem("Option1");
                    it0.addActionListener(new ActionListener() {
                        public void actionPerformed(ActionEvent e) {
                            System.out.println("Option1 on " + node.getUserObject());
                    menu.add(it0);
                    JMenuItem it1 = new JMenuItem("Option2");
                    it1.addActionListener(new ActionListener() {
                        public void actionPerformed(ActionEvent e) {
                            System.out.println("Option2 on " + node.getUserObject());
                    menu.add(it1);
                    menu.show(jtr, e.getX(), e.getY());
            } catch (Throwable t) {
}