Mega Code Archive
Tree Cell Renderer
<![CDATA[
/*
Definitive Guide to Swing for Java 2, Second Edition
By John Zukowski
ISBN: 1-893115-78-X
Publisher: APress
*/
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.GridLayout;
import java.util.Vector;
import javax.swing.BorderFactory;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTree;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.DefaultTreeCellRenderer;
import javax.swing.tree.TreeCellRenderer;
public class BookTree {
public static void main(String args[]) {
JFrame frame = new JFrame("Book Tree");
Book javaBooks[] = {
new Book("Core Java 2 Fundamentals", "Cornell/Horstmann",
42.99f),
new Book("Taming Java Threads", "Holub", 34.95f),
new Book("JavaServer Pages", "Pekowsky", 39.95f) };
Book htmlBooks[] = { new Book("Dynamic HTML", "Goodman", 39.95f),
new Book("HTML 4 Bible", "Pfaffenberger/Gutzman", 49.99f) };
Vector javaVector = new NamedVector("Java Books", javaBooks);
Vector htmlVector = new NamedVector("HTML Books", htmlBooks);
Object rootNodes[] = { javaVector, htmlVector };
Vector rootVector = new NamedVector("Root", rootNodes);
JTree tree = new JTree(rootVector);
TreeCellRenderer renderer = new BookCellRenderer();
tree.setCellRenderer(renderer);
JScrollPane scrollPane = new JScrollPane(tree);
frame.getContentPane().add(scrollPane, BorderLayout.CENTER);
frame.setSize(300, 300);
frame.setVisible(true);
}
}
class Book {
String title;
String authors;
float price;
public Book(String title, String authors, float price) {
this.title = title;
this.authors = authors;
this.price = price;
}
public String getTitle() {
return title;
}
public String getAuthors() {
return authors;
}
public float getPrice() {
return price;
}
}
class BookCellRenderer implements TreeCellRenderer {
JLabel titleLabel;
JLabel authorsLabel;
JLabel priceLabel;
JPanel renderer;
DefaultTreeCellRenderer defaultRenderer = new DefaultTreeCellRenderer();
Color backgroundSelectionColor;
Color backgroundNonSelectionColor;
public BookCellRenderer() {
renderer = new JPanel(new GridLayout(0, 1));
titleLabel = new JLabel(" ");
titleLabel.setForeground(Color.blue);
renderer.add(titleLabel);
authorsLabel = new JLabel(" ");
authorsLabel.setForeground(Color.blue);
renderer.add(authorsLabel);
priceLabel = new JLabel(" ");
priceLabel.setHorizontalAlignment(JLabel.RIGHT);
priceLabel.setForeground(Color.red);
renderer.add(priceLabel);
renderer.setBorder(BorderFactory.createLineBorder(Color.black));
backgroundSelectionColor = defaultRenderer
.getBackgroundSelectionColor();
backgroundNonSelectionColor = defaultRenderer
.getBackgroundNonSelectionColor();
}
public Component getTreeCellRendererComponent(JTree tree, Object value,
boolean selected, boolean expanded, boolean leaf, int row,
boolean hasFocus) {
Component returnValue = null;
if ((value != null) && (value instanceof DefaultMutableTreeNode)) {
Object userObject = ((DefaultMutableTreeNode) value)
.getUserObject();
if (userObject instanceof Book) {
Book book = (Book) userObject;
titleLabel.setText(book.getTitle());
authorsLabel.setText(book.getAuthors());
priceLabel.setText("" + book.getPrice());
if (selected) {
renderer.setBackground(backgroundSelectionColor);
} else {
renderer.setBackground(backgroundNonSelectionColor);
}
renderer.setEnabled(tree.isEnabled());
returnValue = renderer;
}
}
if (returnValue == null) {
returnValue = defaultRenderer.getTreeCellRendererComponent(tree,
value, selected, expanded, leaf, row, hasFocus);
}
return returnValue;
}
}
class NamedVector extends Vector {
String name;
public NamedVector(String name) {
this.name = name;
}
public NamedVector(String name, Object elements[]) {
this.name = name;
for (int i = 0, n = elements.length; i < n; i++) {
add(elements[i]);
}
}
public String toString() {
return "[" + name + "]";
}
}
]]>