import javax.swing.*; import java.awt.Dimension; import java.awt.BorderLayout; import javax.swing.tree.DefaultMutableTreeNode; import javax.swing.event.*; public class JTreeTest15 extends JFrame implements TreeSelectionListener{ JTree tree; JLabel label; public static void main(String[] args){ JTreeTest15 frame = new JTreeTest15(); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.setBounds(10, 10, 300, 200); frame.setTitle("ƒ^ƒCƒgƒ‹"); frame.setVisible(true); } JTreeTest15(){ DefaultMutableTreeNode root = new DefaultMutableTreeNode("JavaDrive"); DefaultMutableTreeNode swing = new DefaultMutableTreeNode("Swing"); DefaultMutableTreeNode java2d = new DefaultMutableTreeNode("Java2D"); DefaultMutableTreeNode java3d = new DefaultMutableTreeNode("Java3D"); DefaultMutableTreeNode javamail = new DefaultMutableTreeNode("JavaMail"); DefaultMutableTreeNode swingSub1 = new DefaultMutableTreeNode("JLabel"); DefaultMutableTreeNode swingSub2 = new DefaultMutableTreeNode("JButton"); DefaultMutableTreeNode swingSub3 = new DefaultMutableTreeNode("JTextField"); swing.add(swingSub1); swing.add(swingSub2); swing.add(swingSub3); root.add(swing); root.add(java2d); root.add(java3d); root.add(javamail); tree = new JTree(root); tree.addTreeSelectionListener(this); JScrollPane scrollPane = new JScrollPane(); scrollPane.getViewport().setView(tree); scrollPane.setPreferredSize(new Dimension(180, 120)); JPanel p = new JPanel(); p.add(scrollPane); label = new JLabel(); JPanel labelPanel = new JPanel(); labelPanel.add(label); getContentPane().add(p, BorderLayout.CENTER); getContentPane().add(labelPanel, BorderLayout.PAGE_END); } public void valueChanged(TreeSelectionEvent e){ DefaultMutableTreeNode node = (DefaultMutableTreeNode)tree.getLastSelectedPathComponent(); if (node != null){ label.setText((String)node.getUserObject()); } }