Java tutorial
/* Definitive Guide to Swing for Java 2, Second Edition By John Zukowski ISBN: 1-893115-78-X Publisher: APress */ import java.awt.Point; import java.awt.event.MouseEvent; import java.util.Arrays; import java.util.Collection; import java.util.Enumeration; import java.util.Iterator; import java.util.Properties; import java.util.SortedSet; import java.util.TreeSet; import javax.swing.AbstractListModel; import javax.swing.JFrame; import javax.swing.JList; import javax.swing.JScrollPane; import javax.swing.ToolTipManager; public class Main { public static void main(String args[]) { JFrame frame = new JFrame("Custom Tip Demo"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); Properties props = System.getProperties(); PropertiesList list = new PropertiesList(props); JScrollPane scrollPane = new JScrollPane(list); frame.getContentPane().add(scrollPane); frame.setSize(300, 300); frame.setVisible(true); } } class PropertiesList extends JList { SortedListModel model; Properties tipProps; public PropertiesList(Properties props) { model = new SortedListModel(); setModel(model); ToolTipManager.sharedInstance().registerComponent(this); tipProps = props; addProperties(props); } private void addProperties(Properties props) { // Load Enumeration e = props.propertyNames(); while (e.hasMoreElements()) { model.add(e.nextElement()); } } public String getToolTipText(MouseEvent event) { Point p = event.getPoint(); int location = locationToIndex(p); String key = (String) model.getElementAt(location); String tip = tipProps.getProperty(key); return tip; } } class SortedListModel extends AbstractListModel { SortedSet model; public SortedListModel() { model = new TreeSet(); } public int getSize() { return model.size(); } public Object getElementAt(int index) { return model.toArray()[index]; } public void add(Object element) { if (model.add(element)) { fireContentsChanged(this, 0, getSize()); } } public void addAll(Object elements[]) { Collection c = Arrays.asList(elements); model.addAll(c); fireContentsChanged(this, 0, getSize()); } public void clear() { model.clear(); fireContentsChanged(this, 0, getSize()); } public boolean contains(Object element) { return model.contains(element); } public Object firstElement() { return model.first(); } public Iterator iterator() { return model.iterator(); } public Object lastElement() { return model.last(); } public boolean removeElement(Object element) { boolean removed = model.remove(element); if (removed) { fireContentsChanged(this, 0, getSize()); } return removed; } }