undoProblem

[eLL Pascual]

I am also having a problem with undo and redo... Please help me again...
I have here my program codes...
This is an SSCCE...

import java.awt.*;
import java.awt.event.*;
import java.awt.event.KeyEvent;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.JMenuBar;
import javax.swing.JMenu;
import javax.swing.JMenuItem;
import javax.swing.KeyStroke;
import javax.swing.JScrollPane;
import java.io.*;
import javax.swing.undo.*;
import javax.swing.text.*;
import java.util.HashMap;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
public class undoProblem extends JPanel implements ActionListener, MouseListener{
static String title;
JTextArea textArea = new JTextArea(0,0);
JScrollPane scrollPane;
static final private String NEW = "new";
static final private String OPEN = "open";
static final private String SAVE = "save";
static final private String CLOSE = "close";
static private String LOCK = "lock";
///POPUP MENU
PopupMenu popup;
MenuItem undoItem, cut, copy, paste, delete, selectAll;
///UNDO REDO
HashMap<Object, Action> actions;
protected UndoAction undoAction;
protected RedoAction redoAction;
protected UndoManager undo = new UndoManager();
////FIND
JLabel findLabel;
JTextField find;
JPanel panel;
//COORDINATES
int textAreaX = 0;
int textAreaY = 0;
boolean checker = false;
String pathOfSave;
public static void main(String ar[]){
SwingUtilities.invokeLater(new Runnable(){
public void run(){
createShowGUI();
UIManager.put("swing.boldMetal",Boolean.FALSE);
}
});
}
public undoProblem(){
popup = new PopupMenu("Menu");
undoItem = new MenuItem("Undo");
undoItem.addActionListener(this);
cut = new MenuItem("Cut");
cut.addActionListener(this);
copy = new MenuItem("Copy");
copy.addActionListener(this);
paste = new MenuItem("Paste");
paste.addActionListener(this);
delete = new MenuItem("Delete");
delete.addActionListener(this);
selectAll = new MenuItem("Select All");
selectAll.addActionListener(this);
popup.add(undoItem);
popup.addSeparator();
popup.add(cut);
popup.add(copy);
popup.add(paste);
popup.add(delete);
popup.addSeparator();
popup.add(selectAll);
actions = createActionTable(textArea);
add(popup);
findLabel = new JLabel("Find: ");
find = new JTextField(15);
panel = new JPanel();
panel.add(findLabel);
panel.add(find);
}
public void mousePressed(MouseEvent me)
{
System.out.print("Mouse Right-Clicked!");
if(me.getModifiers() != 0){
popup.show(this, me.getX(),me.getY());
}
}
public void mouseClicked(MouseEvent e){}
public void mouseReleased(MouseEvent e){}
public void mouseEntered(MouseEvent e){}
public void mouseExited(MouseEvent e){}
public void actionPerformed(ActionEvent ae){
}
private JMenuBar createMenuBar(){
JMenuBar menuBar;
JMenu file, edit, format, view, help;
JMenuItem newItem, open, save, saveAs, pageSetUp, print, exit;
JMenuItem undo, cut, copy, paste, delete, selectAll;
JMenuItem font;
JMenuItem statusBar;
JMenuItem helpTopics, about;
menuBar = new JMenuBar();
file = new JMenu("File");
file.setMnemonic(KeyEvent.VK_F);
edit = new JMenu("Edit");
edit.setMnemonic(KeyEvent.VK_E);
format = new JMenu("Format");
format.setMnemonic(KeyEvent.VK_O);
view = new JMenu("View");
view.setMnemonic(KeyEvent.VK_V);
help = new JMenu("Help");
help.setMnemonic(KeyEvent.VK_H);
menuBar.add(file);
menuBar.add(edit);
menuBar.add(format);
menuBar.add(view);
menuBar.add(help);
///FILE MENU
///EDIT MENU
undo = new JMenuItem("Undo",KeyEvent.VK_1);
undo.setAccelerator(KeyStroke.getKeyStroke(
KeyEvent.VK_Z, ActionEvent.CTRL_MASK));
cut = new JMenuItem("Cut",KeyEvent.VK_1);
cut.setAccelerator(KeyStroke.getKeyStroke(
KeyEvent.VK_X, ActionEvent.CTRL_MASK));
copy = new JMenuItem("Copy",KeyEvent.VK_1);
copy.setAccelerator(KeyStroke.getKeyStroke(
KeyEvent.VK_C, ActionEvent.CTRL_MASK));
paste = new JMenuItem("Paste",KeyEvent.VK_1);
paste.setAccelerator(KeyStroke.getKeyStroke(
KeyEvent.VK_V, ActionEvent.CTRL_MASK));
delete = new JMenuItem("Delete",KeyEvent.VK_1);
delete.setAccelerator(KeyStroke.getKeyStroke(
KeyEvent.VK_DELETE, ActionEvent.SHIFT_MASK));
selectAll = new JMenuItem("Select All",KeyEvent.VK_1);
selectAll.setAccelerator(KeyStroke.getKeyStroke(
KeyEvent.VK_A, ActionEvent.CTRL_MASK));
undoAction = new UndoAction();
redoAction = new RedoAction();
edit.add(undoAction);
edit.add(redoAction);
edit.addSeparator();
edit.add(this.getActionByName(DefaultEditorKit.cutAction));
edit.add(this.getActionByName(DefaultEditorKit.copyAction));
edit.add(this.getActionByName(DefaultEditorKit.pasteAction));
edit.add(this.getActionByName(DefaultEditorKit.deleteNextWordAction));
edit.addSeparator();
edit.add(this.getActionByName(DefaultEditorKit.selectAllAction));
///FORMAT MENU
///VIEW MENU
///HELP MENU
return menuBar;
}
public Container createContentPane(){
JPanel contentPane = new JPanel(new BorderLayout());
contentPane.setOpaque(true);
textArea = new JTextArea(5,10);
textArea.addMouseListener(this);
textArea.setFont(new Font("Courier New", Font.PLAIN, 12));
textArea.setLineWrap(true);
textArea.setWrapStyleWord(true);
scrollPane = new JScrollPane(textArea);
contentPane.add(scrollPane,BorderLayout.CENTER);
contentPane.add(panel,BorderLayout.PAGE_END);
return contentPane;
}
public String titleSetter(){
if(checker == false){
title = "UNTITLED";
}
else if(checker == true){
title = pathOfSave;
}
return title;
}
public static void createShowGUI(){
JFrame frame = new JFrame(/*"Virus Notepad - " + titleSetter()*/);
frame.setVisible(true);
frame.setSize(800,700);
frame.add(new undoProblem());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
undoProblem undo = new undoProblem();
frame.setJMenuBar(undo.createMenuBar());
frame.setContentPane(undo.createContentPane());
frame.setTitle("Notepad - " + undo.titleSetter());
//frame.setAlwaysOnTop(true);
}
//UNDO AND REDO|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
protected class MyUndoableEditListener implements UndoableEditListener {
public void undoableEditHappened(UndoableEditEvent e) {
undo.addEdit(e.getEdit());
undoAction.updateUndoState();
redoAction.updateRedoState();
}
}
protected class MyDocumentListener implements DocumentListener {
public void insertUpdate(DocumentEvent e) {
displayEditInfo(e);
}
public void removeUpdate(DocumentEvent e) {
displayEditInfo(e);
}
public void changedUpdate(DocumentEvent e) {
displayEditInfo(e);
}
private void displayEditInfo(DocumentEvent e) {
Document document = e.getDocument();
int changeLength = e.getLength();
textArea.append(e.getType().toString() + ": " +
changeLength + " character" +
((changeLength == 1) ? ". " : "s. ") +
" Text length = " + document.getLength() +
"." + "/n");
}
}
private HashMap<Object, Action> createActionTable(JTextComponent textComponent) {
HashMap<Object, Action> actions = new HashMap<Object, Action>();
Action[] actionsArray = textComponent.getActions();
for (int i = 0; i < actionsArray.length; i++) {
Action a = actionsArray[i];
actions.put(a.getValue(Action.NAME), a);
}
return actions;
}
private Action getActionByName(String name) {
return actions.get(name);
}
class UndoAction extends AbstractAction {
public UndoAction() {
super("Undo");
setEnabled(false);
}
public void actionPerformed(ActionEvent e) {
try {
undo.undo();
}
catch (CannotUndoException ex) {
System.out.println("Unable to undo: " + ex);
ex.printStackTrace();
}
updateUndoState();
redoAction.updateRedoState();
}
protected void updateUndoState() {
if (undo.canUndo()) {
setEnabled(true);
putValue(Action.NAME, undo.getUndoPresentationName());
} else {
setEnabled(false);
putValue(Action.NAME, "Undo");
}
}
}
class RedoAction extends AbstractAction {
public RedoAction() {
super("Redo");
setEnabled(false);
}
public void actionPerformed(ActionEvent e) {
try {
undo.redo();
} catch (CannotRedoException ex) {
System.out.println("Unable to redo: " + ex);
ex.printStackTrace();
}
updateRedoState();
undoAction.updateUndoState();
}
protected void updateRedoState() {
if (undo.canRedo()) {
setEnabled(true);
putValue(Action.NAME, undo.getRedoPresentationName());
} else {
setEnabled(false);
putValue(Action.NAME, "Redo");
}
}
}
} 

[Ulf Dittmer]

I'm sorry, but you have to be kidding. There is nothing "short" about this code excerpt. Plus, how are we supposed to figure out what's going on if you neither describe what the code is supposed to be doing, nor what it is actually doing?

[eLL Pascual]

So it has to be really short?

Oh my God, I dont know how to make that short because I guess this is the shortest it can be. All the codes here are necessary to run the program and address my problem.

This program is a notepad...
The problem here is that I am trying to make the program capable of using undo but the problem is it cannot tell weather an action happened.
[ July 11, 2008: Message edited by: eLL Pascual ]

[Maneesh Godbole]

 

Originally posted by eLL Pascual:
...The problem here is that I am trying to make the problem capable of using undo but the problem is it cannot tell weather an action happened.

Well you can always confirm this either by running your application in a debugger or having SOP statements in your actions.

These links might also be useful.
http://jroller.com/santhosh/entry/implementing_undo_redo_in_right

http://jroller.com/santhosh/entry/implementing_undo_redo_in_right1
[ July 01, 2008: Message edited by: Maneesh Godbole ]