Mega Code Archive
Tree Expand Event Demo 2
<![CDATA[
/* From http://java.sun.com/docs/books/tutorial/index.html */
/*
* Copyright (c) 2006 Sun Microsystems, Inc. All Rights Reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* -Redistribution of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* -Redistribution in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* Neither the name of Sun Microsystems, Inc. or the names of contributors may
* be used to endorse or promote products derived from this software without
* specific prior written permission.
*
* This software is provided "AS IS," without a warranty of any kind. ALL
* EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING
* ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE
* OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN MIDROSYSTEMS, INC. ("SUN")
* AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE
* AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS
* DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST
* REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL,
* INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY
* OF LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE,
* EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
*
* You acknowledge that this software is not designed, licensed or intended
* for use in the design, construction, operation or maintenance of any
* nuclear facility.
*/
/*
* TreeExpandEventDemo2.java is a 1.4 example that requires no other files.
*/
import java.awt.Dimension;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import javax.swing.BorderFactory;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTree;
import javax.swing.event.TreeExpansionEvent;
import javax.swing.event.TreeExpansionListener;
import javax.swing.event.TreeWillExpandListener;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.ExpandVetoException;
import javax.swing.tree.TreeNode;
public class TreeExpandEventDemo2 extends JPanel {
DemoArea demoArea;
JTextArea textArea;
final static String newline = "\n";
public TreeExpandEventDemo2() {
super(new GridBagLayout());
GridBagLayout gridbag = (GridBagLayout) getLayout();
GridBagConstraints c = new GridBagConstraints();
c.fill = GridBagConstraints.BOTH;
c.gridwidth = GridBagConstraints.REMAINDER;
c.weightx = 1.0;
c.weighty = 1.0;
c.insets = new Insets(1, 1, 1, 1);
demoArea = new DemoArea();
gridbag.setConstraints(demoArea, c);
add(demoArea);
c.insets = new Insets(0, 0, 0, 0);
textArea = new JTextArea();
textArea.setEditable(false);
JScrollPane scrollPane = new JScrollPane(textArea);
scrollPane
.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
scrollPane.setPreferredSize(new Dimension(200, 75));
gridbag.setConstraints(scrollPane, c);
add(scrollPane);
setPreferredSize(new Dimension(450, 450));
setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
}
void saySomething(String eventDescription, TreeExpansionEvent e) {
textArea.append(eventDescription + "; " + "path = " + e.getPath()
+ newline);
}
class DemoArea extends JScrollPane implements TreeExpansionListener,
TreeWillExpandListener {
Dimension minSize = new Dimension(100, 100);
JTree tree;
Object[] willExpandOptions = { "Cancel Expansion", "Expand" };
String willExpandText = "A branch node is about to be expanded.\n"
+ "Click \"Cancel Expansion\" to prevent it.";
String willExpandTitle = "Tree Will Expand";
public DemoArea() {
TreeNode rootNode = createNodes();
tree = new JTree(rootNode);
tree.addTreeExpansionListener(this);
tree.addTreeWillExpandListener(this);
setViewportView(tree);
}
private TreeNode createNodes() {
DefaultMutableTreeNode root;
DefaultMutableTreeNode grandparent;
DefaultMutableTreeNode parent;
DefaultMutableTreeNode child;
root = new DefaultMutableTreeNode("San Francisco");
grandparent = new DefaultMutableTreeNode("Potrero Hill");
root.add(grandparent);
//
parent = new DefaultMutableTreeNode("Restaurants");
grandparent.add(parent);
child = new DefaultMutableTreeNode("Thai Barbeque");
parent.add(child);
child = new DefaultMutableTreeNode("Goat Hill Pizza");
parent.add(child);
//
parent = new DefaultMutableTreeNode("Grocery Stores");
grandparent.add(parent);
child = new DefaultMutableTreeNode("Good Life Grocery");
parent.add(child);
child = new DefaultMutableTreeNode("Safeway");
parent.add(child);
grandparent = new DefaultMutableTreeNode("Noe Valley");
root.add(grandparent);
//
parent = new DefaultMutableTreeNode("Restaurants");
grandparent.add(parent);
child = new DefaultMutableTreeNode("Hamano Sushi");
parent.add(child);
child = new DefaultMutableTreeNode("Hahn's Hibachi");
parent.add(child);
//
parent = new DefaultMutableTreeNode("Grocery Stores");
grandparent.add(parent);
child = new DefaultMutableTreeNode("Real Foods");
parent.add(child);
child = new DefaultMutableTreeNode("Bell Market");
parent.add(child);
return root;
}
public Dimension getMinimumSize() {
return minSize;
}
public Dimension getPreferredSize() {
return minSize;
}
//Required by TreeWillExpandListener interface.
public void treeWillExpand(TreeExpansionEvent e)
throws ExpandVetoException {
saySomething("Tree-will-expand event detected", e);
int n = JOptionPane.showOptionDialog(this, willExpandText,
willExpandTitle, JOptionPane.YES_NO_OPTION,
JOptionPane.QUESTION_MESSAGE, null, willExpandOptions,
willExpandOptions[1]);
if (n == 0) {
//User said cancel expansion.
saySomething("Tree expansion cancelled", e);
throw new ExpandVetoException(e);
}
}
//Required by TreeWillExpandListener interface.
public void treeWillCollapse(TreeExpansionEvent e) {
saySomething("Tree-will-collapse event detected", e);
}
// Required by TreeExpansionListener interface.
public void treeExpanded(TreeExpansionEvent e) {
saySomething("Tree-expanded event detected", e);
}
// Required by TreeExpansionListener interface.
public void treeCollapsed(TreeExpansionEvent e) {
saySomething("Tree-collapsed event detected", e);
}
}
/**
* Create the GUI and show it. For thread safety, this method should be
* invoked from the event-dispatching thread.
*/
private static void createAndShowGUI() {
//Make sure we have nice window decorations.
JFrame.setDefaultLookAndFeelDecorated(true);
//Create and set up the window.
JFrame frame = new JFrame("TreeExpandEventDemo2");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//Create and set up the content pane.
JComponent newContentPane = new TreeExpandEventDemo2();
newContentPane.setOpaque(true); //content panes must be opaque
frame.setContentPane(newContentPane);
//Display the window.
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
//Schedule a job for the event-dispatching thread:
//creating and showing this application's GUI.
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
}
]]>