Thread: Adding a JScrollPane to a JTree

I can't get the scrollpane to appear here:

package oldschool.runescape.com;
 
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URL;
import java.net.URLConnection;
import java.util.HashMap;
import java.util.Map;
import java.util.Map.Entry;
import java.util.regex.Pattern;
 
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTree;
import javax.swing.border.EmptyBorder;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.DefaultTreeModel;
 
public class Worlds extends JFrame {
 
	private static final long serialVersionUID = 445871530648558835L;
 
	private JPanel contentPane;
	private Map<String, Integer> worlds = new HashMap<String, Integer>(); 
	private String site = "http://oldschool.runescape.com/slu.ws?order=WpMLA";
 
	/**
	 * Launch the application.
	 */
	public static void main(String[] args) {
		EventQueue.invokeLater(new Runnable() {
			public void run() {
				try {
					Worlds frame = new Worlds();
					frame.setVisible(true);
					frame.prepareWorlds();
				} catch (Exception e) {
					e.printStackTrace();
				}
			}
		});
	}
 
	private void prepareWorlds() {
		final Pattern pattern = Pattern.compile("d.write");
		try {
			URL url = new URL(site);
			URLConnection curl = url.openConnection();
			curl.setDoInput(true);
			InputStream instr = curl.getInputStream();
			String s;
			if (instr != null) {
				BufferedReader in = new BufferedReader(new InputStreamReader(
						instr));
				while ((s = in.readLine()) != null) {
					if (pattern.matcher(s).find()) {
						while ((s = in.readLine()) != null) {
							if (s == null || s.equalsIgnoreCase("") || s.equalsIgnoreCase(" ")) continue;
							if (s.equals("</script>")) break;
							String data = s;
 
							final Pattern school = Pattern.compile("oldschool.*?");
							if (school.matcher(data).find()) {
								String[] newStrings = data.split("\"");
								String name = newStrings[1];
								int count = Integer.parseInt(data.split(",")[4]);
								worlds.put(name, count);
							}
						}
					}
				}
			}
			for (Entry<String, Integer> v : worlds.entrySet()) {
				dropsNode.add(new DefaultMutableTreeNode(v.getKey()));
			}
		} catch (Throwable t) {
			t.printStackTrace();
		}
	}
 
	private DefaultMutableTreeNode dropsNode = new DefaultMutableTreeNode("Worlds");
	private DefaultTreeModel dropsTreeModel = new DefaultTreeModel(dropsNode);
	private JTree tree = new JTree();
	private JScrollPane treeScroll = new JScrollPane();
 
	/**
	 * Create the frame.
	 */
	public Worlds() {
		prepareWorlds();	
 
 
		setTitle("07 World Picker");
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		setBounds(100, 100, 414, 295);
		contentPane = new JPanel();
		contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
		setContentPane(contentPane);
		contentPane.setLayout(null);
 
		JButton btnGo = new JButton("GO!");
		btnGo.setBounds(125, 222, 129, 23);
		contentPane.add(btnGo);
 
		JLabel lblPickAWorld = new JLabel("Pick a world:");
		lblPickAWorld.setBounds(10, 11, 129, 23);
		contentPane.add(lblPickAWorld);
 
		tree.setBounds(125, 14, 129, 114);
		tree.setModel(dropsTreeModel);
 
		treeScroll.add(tree);
		contentPane.add(tree);
 
		btnGo.addActionListener(new ActionListener() {
 
			@Override
			public void actionPerformed(ActionEvent e) {
				try {
					//RS2Loader.startUp(tree.getSelectionModel().getSelectionPath().getLastPathComponent());
				} catch (Exception e1) {
					e1.printStackTrace();
				}
				setVisible(false);
			}
		});
	}
}

It appears like this:

There is no scroll bar, theres more than 4 values in the tree but they arent visible.

		contentPane.add(treeScroll);

Makes no difference. Am I doing something wrong in my code?

Originally Posted by Norm

Did you read the API doc to see how to use the JScrollPane?

Yes I have I'm still hopelessly lost as to what I'm doing wrong. I've been searching for hours on end. Can you just tell me what to do