Java Tree (JTree) - Swing Example

DefaultMutableTreeNode treeRoot = new DefaultMutableTreeNode("Root");

// Item 1
DefaultMutableTreeNode item1 = new DefaultMutableTreeNode("Item 1");
item1.add(new DefaultMutableTreeNode("Item 1 - 1"));
item1.add(new DefaultMutableTreeNode("Item 1 - 2"));
item1.add(new DefaultMutableTreeNode("Item 1 - 3"));
item1.add(new DefaultMutableTreeNode("Item 1 - 4"));

// Item 2
DefaultMutableTreeNode item2 = new DefaultMutableTreeNode("Item 2");
item2.add(new DefaultMutableTreeNode("Item 2 - 1"));
item2.add(new DefaultMutableTreeNode("Item 2 - 2"));
item2.add(new DefaultMutableTreeNode("Item 2 - 3"));
item2.add(new DefaultMutableTreeNode("Item 2 - 4"));
item2.add(new DefaultMutableTreeNode("Item 2 - 5"));
item2.add(new DefaultMutableTreeNode("Item 2 - 6"));

// Selected Node
tree.getSelectionModel().addTreeSelectionListener(
		new TreeSelectionListener() {
			@Override
			public void valueChanged(TreeSelectionEvent e) {
				DefaultMutableTreeNode selectedNode = (DefaultMutableTreeNode) tree
						.getLastSelectedPathComponent();

				JOptionPane.showMessageDialog(null, selectedNode
						.getUserObject().toString());
			}
		});

package com.java.myapp;

import java.awt.EventQueue;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JScrollPane;
import javax.swing.JTree;
import javax.swing.event.TreeSelectionEvent;
import javax.swing.event.TreeSelectionListener;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.DefaultTreeCellRenderer;

public class MyForm extends JFrame {

	/**
	 * Launch the application.
	 */
	public static void main(String[] args) {
		EventQueue.invokeLater(new Runnable() {
			public void run() {
				MyForm frame = new MyForm();
				frame.setVisible(true);
			}
		});
	}

	/**
	 * Create the frame.
	 */
	public MyForm() {
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		setBounds(100, 100, 362, 249);
		setTitle("ThaiCreate.Com Java GUI Tutorial");
		getContentPane().setLayout(null);
		
		// Root
		DefaultMutableTreeNode treeRoot = new DefaultMutableTreeNode("Root");

		// Item 1
		DefaultMutableTreeNode item1 = new DefaultMutableTreeNode("Item 1");

		// Item 2
		DefaultMutableTreeNode item2 = new DefaultMutableTreeNode("Item 2");

		
		// Add Item Node Item 1 & Item 2
		treeRoot.add(item1);
		treeRoot.add(item2);

		// Tree
		final JTree tree = new JTree(treeRoot);
		tree.setBounds(28, 11, 209, 131);

		// Scroll Pane
		JScrollPane scroll = new JScrollPane();
		scroll.setBounds(28, 11, 209, 169);

		// Image Icon
		ImageIcon imageIcon = new ImageIcon(getClass().getResource("open.gif"));
		
		DefaultTreeCellRenderer renderer = new DefaultTreeCellRenderer();
		renderer.setLeafIcon(imageIcon);

		tree.setCellRenderer(renderer);
		tree.setShowsRootHandles(true);
		tree.setRootVisible(false);

		// Add Scroll and Tree
		scroll.setViewportView(tree);
		getContentPane().add(scroll);

		// Selected
		tree.getSelectionModel().addTreeSelectionListener(
				new TreeSelectionListener() {
					@Override
					public void valueChanged(TreeSelectionEvent e) {
						DefaultMutableTreeNode selectedNode = (DefaultMutableTreeNode) tree
								.getLastSelectedPathComponent();

						JOptionPane.showMessageDialog(null, selectedNode
								.getUserObject().toString());
					}
				});

	}
}

package com.java.myapp;

import java.awt.EventQueue;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JScrollPane;
import javax.swing.JTree;
import javax.swing.event.TreeSelectionEvent;
import javax.swing.event.TreeSelectionListener;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.DefaultTreeCellRenderer;

public class MyForm extends JFrame {

	/**
	 * Launch the application.
	 */
	public static void main(String[] args) {
		EventQueue.invokeLater(new Runnable() {
			public void run() {
				MyForm frame = new MyForm();
				frame.setVisible(true);
			}
		});
	}

	/**
	 * Create the frame.
	 */
	public MyForm() {
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		setBounds(100, 100, 362, 249);
		setTitle("ThaiCreate.Com Java GUI Tutorial");
		getContentPane().setLayout(null);
		
		// Root
		DefaultMutableTreeNode treeRoot = new DefaultMutableTreeNode("Root");

		// Item 1
		DefaultMutableTreeNode item1 = new DefaultMutableTreeNode("Item 1");
		item1.add(new DefaultMutableTreeNode("Item 1 - 1"));
		item1.add(new DefaultMutableTreeNode("Item 1 - 2"));
		item1.add(new DefaultMutableTreeNode("Item 1 - 3"));
		item1.add(new DefaultMutableTreeNode("Item 1 - 4"));

		// Item 2
		DefaultMutableTreeNode item2 = new DefaultMutableTreeNode("Item 2");
		item2.add(new DefaultMutableTreeNode("Item 2 - 1"));
		item2.add(new DefaultMutableTreeNode("Item 2 - 2"));
		item2.add(new DefaultMutableTreeNode("Item 2 - 3"));
		item2.add(new DefaultMutableTreeNode("Item 2 - 4"));
		item2.add(new DefaultMutableTreeNode("Item 2 - 5"));
		item2.add(new DefaultMutableTreeNode("Item 2 - 6"));

		// Add Item Node Item 1 & Item 2
		treeRoot.add(item1);
		treeRoot.add(item2);

		// Tree
		final JTree tree = new JTree(treeRoot);
		tree.setBounds(28, 11, 209, 131);

		// Scroll Pane
		JScrollPane scroll = new JScrollPane();
		scroll.setBounds(28, 11, 209, 169);

		// Image Icon
		ImageIcon imageIcon = new ImageIcon(getClass().getResource("open.gif"));
		DefaultTreeCellRenderer renderer = new DefaultTreeCellRenderer();
		renderer.setLeafIcon(imageIcon);

		tree.setCellRenderer(renderer);
		tree.setShowsRootHandles(true);
		tree.setRootVisible(false);

		// Add Scroll and Tree
		scroll.setViewportView(tree);
		getContentPane().add(scroll);

		// Selected
		tree.getSelectionModel().addTreeSelectionListener(
				new TreeSelectionListener() {
					@Override
					public void valueChanged(TreeSelectionEvent e) {
						DefaultMutableTreeNode selectedNode = (DefaultMutableTreeNode) tree
								.getLastSelectedPathComponent();

						JOptionPane.showMessageDialog(null, selectedNode
								.getUserObject().toString());
					}
				});

	}
}

package com.java.myapp;

import java.awt.EventQueue;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JScrollPane;
import javax.swing.JTree;
import javax.swing.event.TreeSelectionEvent;
import javax.swing.event.TreeSelectionListener;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.DefaultTreeCellRenderer;

public class MyForm extends JFrame {

	/**
	 * Launch the application.
	 */
	public static void main(String[] args) {
		EventQueue.invokeLater(new Runnable() {
			public void run() {
				MyForm frame = new MyForm();
				frame.setVisible(true);
			}
		});
	}

	/**
	 * Create the frame.
	 */
	public MyForm() {
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		setBounds(100, 100, 362, 249);
		setTitle("ThaiCreate.Com Java GUI Tutorial");
		getContentPane().setLayout(null);
		
		// Root
		DefaultMutableTreeNode treeRoot = new DefaultMutableTreeNode("Root");

		// Item 1
		DefaultMutableTreeNode item1 = new DefaultMutableTreeNode("Item 1");
		item1.add(new DefaultMutableTreeNode("Item 1 - 1"));
		item1.add(new DefaultMutableTreeNode("Item 1 - 2"));
		item1.add(new DefaultMutableTreeNode("Item 1 - 3"));
		item1.add(new DefaultMutableTreeNode("Item 1 - 4"));

		// Item 2
		DefaultMutableTreeNode item2 = new DefaultMutableTreeNode("Item 2");
		item2.add(new DefaultMutableTreeNode("Item 2 - 1"));
		item2.add(new DefaultMutableTreeNode("Item 2 - 2"));
		item2.add(new DefaultMutableTreeNode("Item 2 - 3"));
		item2.add(new DefaultMutableTreeNode("Item 2 - 4"));
		
		// Item Sub 2
		DefaultMutableTreeNode itemSub2 = new DefaultMutableTreeNode("Item 2");
		itemSub2.add(new DefaultMutableTreeNode("Item Sub 2 - 1"));
		itemSub2.add(new DefaultMutableTreeNode("Item Sub 2 - 2"));
		
		// Add Item Node Item 1 & Item 2
		treeRoot.add(item1);
		treeRoot.add(item2);
		item2.add(itemSub2);

		// Tree
		final JTree tree = new JTree(treeRoot);
		tree.setBounds(28, 11, 209, 131);

		// Scroll Pane
		JScrollPane scroll = new JScrollPane();
		scroll.setBounds(28, 11, 209, 169);

		// Image Icon
		ImageIcon imageIcon = new ImageIcon(getClass().getResource("open.gif"));
		DefaultTreeCellRenderer renderer = new DefaultTreeCellRenderer();
		renderer.setLeafIcon(imageIcon);

		tree.setCellRenderer(renderer);
		tree.setShowsRootHandles(true);
		tree.setRootVisible(false);

		// Add Scroll and Tree
		scroll.setViewportView(tree);
		getContentPane().add(scroll);

		// Selected
		tree.getSelectionModel().addTreeSelectionListener(
				new TreeSelectionListener() {
					@Override
					public void valueChanged(TreeSelectionEvent e) {
						DefaultMutableTreeNode selectedNode = (DefaultMutableTreeNode) tree
								.getLastSelectedPathComponent();

						JOptionPane.showMessageDialog(null, selectedNode
								.getUserObject().toString());
					}
				});

	}
}