Add undo support to the StyleFrame example : Undo Redo « Swing JFC « Java
Add undo support to the StyleFrame example
/*
Java Swing, 2nd Edition
By Marc Loy, Robert Eckstein, Dave Wood, James Elliott, Brian Cole
ISBN: 0-596-00408-7
Publisher: O'Reilly
*/
// UndoStyleFrame.java
//Add undo support to the StyleFrame example. This example only
//retains the most recent edit, to keep things simple.
import java.awt.BorderLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.AbstractAction;
import javax.swing.JButton;
import javax.swing.JCheckBox;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextField;
import javax.swing.JTextPane;
import javax.swing.SwingConstants;
import javax.swing.event.UndoableEditEvent;
import javax.swing.event.UndoableEditListener;
import javax.swing.text.Style;
import javax.swing.text.StyleConstants;
import javax.swing.text.StyleContext;
import javax.swing.undo.UndoableEdit;
public class UndoStyleFrame extends StyleFrame {
protected UndoAct undoAction = new UndoAct(); // an Action for undo
protected RedoAct redoAction = new RedoAct(); // an Action for redo
public UndoStyleFrame() {
super();
setTitle("UndoStyleFrame");
// register the Actions as undo listeners (we inherited textPane)
textPane.getDocument().addUndoableEditListener(undoAction);
textPane.getDocument().addUndoableEditListener(redoAction);
// create menu for undo/redo
JMenu editMenu = new JMenu("Edit");
editMenu.add(new JMenuItem(undoAction));
editMenu.add(new JMenuItem(redoAction));
menuBar.add(editMenu); // we inherited menuBar from superclass
// create buttons for undo/redo
JPanel buttonPanel = new JPanel();
buttonPanel.add(new JButton(undoAction));
buttonPanel.add(new JButton(redoAction));
getContentPane().add(buttonPanel, java.awt.BorderLayout.SOUTH);
}
// begin inner classes ------------
public class UndoAct extends AbstractAction implements UndoableEditListener {
private UndoableEdit edit;
public UndoAct() {
super("Undo");
setEnabled(false);
}
public void updateEnabled() {
setEnabled(edit.canUndo());
}
public void undoableEditHappened(UndoableEditEvent event) {
edit = event.getEdit();
putValue(NAME, edit.getUndoPresentationName());
updateEnabled();
}
public void actionPerformed(ActionEvent ae) {
edit.undo();
updateEnabled(); // disable undo
redoAction.updateEnabled(); // enable redo
}
}
public class RedoAct extends AbstractAction implements UndoableEditListener {
private UndoableEdit edit;
public RedoAct() {
super("Redo");
setEnabled(false);
}
public void updateEnabled() {
setEnabled(edit.canRedo());
}
public void undoableEditHappened(UndoableEditEvent event) {
edit = event.getEdit();
putValue(NAME, edit.getRedoPresentationName());
updateEnabled();
}
public void actionPerformed(ActionEvent ae) {
edit.redo();
updateEnabled(); // disable redo
undoAction.updateEnabled(); // enable undo
}
}
// end inner classes ------------
public static void main(String[] args) {
JFrame frame = new UndoStyleFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(400, 300);
frame.setVisible(true);
}
}
//StyleFrame.java
//A JTextPane with a menu for Style manipulation.
class StyleFrame extends JFrame implements ActionListener {
protected StyleBox styleBox;
protected JTextPane textPane;
protected JMenuBar menuBar;
protected JMenu applyStyleMenu, modifyStyleMenu;
protected JMenuItem createItem;
public StyleFrame() {
super("StyleFrame");
styleBox = new StyleBox();
textPane = new JTextPane();
getContentPane().add(new JScrollPane(textPane), BorderLayout.CENTER);
// set up menu
menuBar = new JMenuBar();
JMenu styleMenu = new JMenu("Style");
menuBar.add(styleMenu);
setJMenuBar(menuBar);
applyStyleMenu = new JMenu("Set Logical Style");
applyStyleMenu
.setToolTipText("set the Logical Style for the paragraph at caret location");
styleMenu.add(applyStyleMenu);
modifyStyleMenu = new JMenu("Modify Style");
modifyStyleMenu
.setToolTipText("redefine a named Style (will affect paragraphs using that style)");
styleMenu.add(modifyStyleMenu);
createItem = new JMenuItem("Create New Style");
createItem
.setToolTipText("define a new Style (which can then be applied to paragraphs)");
createItem.addActionListener(this);
styleMenu.add(createItem);
// add the default style to applyStyleMenu and modifyStyleMenu
createMenuItems(StyleContext.DEFAULT_STYLE);
}
protected void createMenuItems(String styleName) {
// add 'styleName' to applyStyleMenu and modifyStyleMenu
JMenuItem applyItem = new JMenuItem(styleName);
applyItem.addActionListener(this);
applyStyleMenu.add(applyItem);
JMenuItem modifyItem = new JMenuItem(styleName);
modifyItem.addActionListener(this);
modifyStyleMenu.add(modifyItem);
}
public void actionPerformed(ActionEvent e) {
// determine which menuItem was invoked and process it
JMenuItem source = (JMenuItem) e.getSource();
if (applyStyleMenu.isMenuComponent(source)) {
// apply an existing style to the paragraph at the caret position
String styleName = source.getActionCommand();
Style style = textPane.getStyle(styleName);
textPane.setLogicalStyle(style);
}
if (source == createItem) {
// define a new Style and add it to the menus
styleBox.clear();
int response = JOptionPane.showConfirmDialog(this, styleBox,
"Style Editor", JOptionPane.OK_CANCEL_OPTION,
JOptionPane.PLAIN_MESSAGE);
if (response == JOptionPane.OK_OPTION
&& styleBox.getStyleName().length() > 0) {
String styleName = styleBox.getStyleName();
Style style = textPane.addStyle(styleName, null);
styleBox.fillStyle(style);
createMenuItems(styleName); // add new Style to the menus
}
}
if (modifyStyleMenu.isMenuComponent(source)) {
// redefine a Style (will automatically redraw paragraphs using
// Style)
String styleName = source.getActionCommand();
Style style = textPane.getStyle(styleName);
styleBox.loadFromStyle(style);
int response = JOptionPane.showConfirmDialog(this, styleBox,
"Style Editor", JOptionPane.OK_CANCEL_OPTION,
JOptionPane.PLAIN_MESSAGE);
if (response == JOptionPane.OK_OPTION)
styleBox.fillStyle(style);
}
}
public static void main(String[] args) {
JFrame frame = new StyleFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(400, 300);
frame.setVisible(true);
}
}
//StyleBox.java
//A control panel that can be used to edit a style's paragraph attributes.
class StyleBox extends JPanel {
private static final String[] fonts = { "Monospaced", "Serif", "SansSerif" };
private static final String[] sizes = { "8", "10", "12", "18", "24", "36" };
private JTextField nameField;
private JComboBox fontCombo, sizeCombo;
private JTextField leftField, rightField, aboveField, belowField;
private JCheckBox boldCheck, italicCheck;
public StyleBox() {
// create the fields and lay them out
super(new BorderLayout(4, 4));
JPanel labelPanel = new JPanel(new GridLayout(8, 1, 0, 2));
JPanel valuePanel = new JPanel(new GridLayout(8, 1, 0, 2));
add(labelPanel, BorderLayout.WEST);
add(valuePanel, BorderLayout.CENTER);
JLabel lab;
JPanel sidePanel;
lab = new JLabel("Style Name", SwingConstants.RIGHT);
labelPanel.add(lab);
nameField = new JTextField();
lab.setLabelFor(nameField);
valuePanel.add(nameField);
lab = new JLabel("Font", SwingConstants.RIGHT);
labelPanel.add(lab);
fontCombo = new JComboBox(fonts);
fontCombo.setEditable(true); // user may enter custom value
lab.setLabelFor(fontCombo);
valuePanel.add(fontCombo);
lab = new JLabel("Size", SwingConstants.RIGHT);
labelPanel.add(lab);
sizeCombo = new JComboBox(sizes);
sizeCombo.setEditable(true); // user may enter custom value
lab.setLabelFor(sizeCombo);
sidePanel = new JPanel(new BorderLayout(4, 0));
sidePanel.add(sizeCombo, BorderLayout.CENTER);
sidePanel.add(new JLabel("points"), BorderLayout.EAST);
valuePanel.add(sidePanel);
lab = new JLabel("Left Indent", SwingConstants.RIGHT);
labelPanel.add(lab);
leftField = new JTextField();
lab.setLabelFor(leftField);
sidePanel = new JPanel(new BorderLayout(4, 0));
sidePanel.add(leftField, BorderLayout.CENTER);
sidePanel.add(new JLabel("points"), BorderLayout.EAST);
valuePanel.add(sidePanel);
lab = new JLabel("Right Indent", SwingConstants.RIGHT);
labelPanel.add(lab);
rightField = new JTextField();
lab.setLabelFor(rightField);
sidePanel = new JPanel(new BorderLayout(4, 0));
sidePanel.add(rightField, BorderLayout.CENTER);
sidePanel.add(new JLabel("points"), BorderLayout.EAST);
valuePanel.add(sidePanel);
lab = new JLabel("Space Above", SwingConstants.RIGHT);
labelPanel.add(lab);
aboveField = new JTextField();
lab.setLabelFor(aboveField);
sidePanel = new JPanel(new BorderLayout(4, 0));
sidePanel.add(aboveField, BorderLayout.CENTER);
sidePanel.add(new JLabel("points"), BorderLayout.EAST);
valuePanel.add(sidePanel);
lab = new JLabel("Space Below", SwingConstants.RIGHT);
labelPanel.add(lab);
belowField = new JTextField();
lab.setLabelFor(belowField);
sidePanel = new JPanel(new BorderLayout(4, 0));
sidePanel.add(belowField, BorderLayout.CENTER);
sidePanel.add(new JLabel("points"), BorderLayout.EAST);
valuePanel.add(sidePanel);
boldCheck = new JCheckBox("Bold");
italicCheck = new JCheckBox("Italic");
sidePanel = new JPanel(new GridLayout(1, 2));
sidePanel.add(boldCheck);
sidePanel.add(italicCheck);
valuePanel.add(sidePanel);
clear(); // sets initial values, etc.
}
public void clear() {
// reset all fields (also sets nameField to be editable)
nameField.setText("");
nameField.setEditable(true);
fontCombo.setSelectedIndex(0);
sizeCombo.setSelectedIndex(2);
leftField.setText("0.0");
rightField.setText("0.0");
aboveField.setText("0.0");
belowField.setText("0.0");
boldCheck.setSelected(false);
italicCheck.setSelected(false);
}
public String getStyleName() {
// return the name of the style
String name = nameField.getText();
if (name.length() > 0)
return name;
else
return null;
}
public void fillStyle(Style style) {
// mutate 'style' with the values entered in the fields
// (no value checking--could throw NumberFormatException)
String font = (String) fontCombo.getSelectedItem();
StyleConstants.setFontFamily(style, font);
String size = (String) sizeCombo.getSelectedItem();
StyleConstants.setFontSize(style, Integer.parseInt(size));
String left = leftField.getText();
StyleConstants.setLeftIndent(style, Float.valueOf(left).floatValue());
String right = rightField.getText();
StyleConstants.setRightIndent(style, Float.valueOf(right).floatValue());
String above = aboveField.getText();
StyleConstants.setSpaceAbove(style, Float.valueOf(above).floatValue());
String below = belowField.getText();
StyleConstants.setSpaceBelow(style, Float.valueOf(below).floatValue());
boolean bold = boldCheck.isSelected();
StyleConstants.setBold(style, bold);
boolean italic = italicCheck.isSelected();
StyleConstants.setItalic(style, italic);
}
// Load the form from an existing Style.
public void loadFromStyle(Style style) {
nameField.setText(style.getName());
nameField.setEditable(false); // don't allow name change
String fam = StyleConstants.getFontFamily(style);
fontCombo.setSelectedItem(fam);
int size = StyleConstants.getFontSize(style);
sizeCombo.setSelectedItem(Integer.toString(size));
float left = StyleConstants.getLeftIndent(style);
leftField.setText(Float.toString(left));
float right = StyleConstants.getRightIndent(style);
rightField.setText(Float.toString(right));
float above = StyleConstants.getSpaceAbove(style);
aboveField.setText(Float.toString(above));
float below = StyleConstants.getSpaceBelow(style);
belowField.setText(Float.toString(below));
boolean bold = StyleConstants.isBold(style);
boldCheck.setSelected(bold);
boolean italic = StyleConstants.isItalic(style);
italicCheck.setSelected(italic);
}
}
