Java by API/javax.swing.undo/UndoableEditSupport

UndoableEditSupport: addUndoableEditListener(UndoableEditListener l)

   <source lang="java">

import java.awt.BorderLayout; import java.awt.ruponent; import java.awt.Container; import java.awt.Graphics; import java.awt.Polygon; import java.awt.event.ActionEvent; import java.awt.event.MouseAdapter; import java.awt.event.MouseEvent; import java.awt.event.MouseListener; import javax.swing.AbstractAction; import javax.swing.Action; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JOptionPane; import javax.swing.JPanel; import javax.swing.JToolBar; import javax.swing.UIManager; import javax.swing.event.UndoableEditListener; import javax.swing.undo.AbstractUndoableEdit; import javax.swing.undo.CannotRedoException; import javax.swing.undo.CannotUndoException; import javax.swing.undo.UndoManager; import javax.swing.undo.UndoableEditSupport; public class UndoDrawing {

 public static void main(String args[]) {
   JFrame frame = new JFrame("Drawing Sample");
   frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   UndoableDrawingPanel drawingPanel = new UndoableDrawingPanel();
   UndoManager manager = new UndoManager();
   drawingPanel.addUndoableEditListener(manager);
   JToolBar toolbar = new JToolBar();
   JButton undoButton = new JButton(UndoManagerHelper.getUndoAction(manager));
   toolbar.add(undoButton);
   JButton redoButton = new JButton(UndoManagerHelper.getRedoAction(manager));
   toolbar.add(redoButton);
   Container content = frame.getContentPane();
   content.add(toolbar, BorderLayout.NORTH);
   content.add(drawingPanel, BorderLayout.CENTER);
   frame.setSize(300, 150);
   frame.setVisible(true);
 }

} class UndoableDrawEdit extends AbstractUndoableEdit {

 UndoableDrawingPanel panel;
 Polygon polygon, savedPolygon;
 public UndoableDrawEdit(UndoableDrawingPanel panel) {
   this.panel = panel;
   polygon = panel.getPolygon();
 }
 public String getPresentationName() {
   return "Polygon of size " + polygon.npoints;
 }
 public void redo() throws CannotRedoException {
   super.redo();
   if (savedPolygon == null) {
     // Should never get here, as super() doesn"t permit redoing
     throw new CannotRedoException();
   } else {
     panel.setPolygon(savedPolygon);
     savedPolygon = null;
   }
 }
 public void undo() throws CannotUndoException {
   super.undo();
   savedPolygon = panel.getPolygon();
   panel.setPolygon(polygon);
 }

} class UndoableDrawingPanel extends JPanel {

 UndoableEditSupport undoableEditSupport = new UndoableEditSupport(this);
 Polygon polygon = new Polygon();
 public UndoableDrawingPanel() {
   MouseListener mouseListener = new MouseAdapter() {
     public void mouseReleased(MouseEvent mouseEvent) {
       undoableEditSupport.postEdit(new UndoableDrawEdit(UndoableDrawingPanel.this));
       polygon.addPoint(mouseEvent.getX(), mouseEvent.getY());
       repaint();
     }
   };
   addMouseListener(mouseListener);
 }
 public void addUndoableEditListener(UndoableEditListener undoableEditListener) {
   undoableEditSupport.addUndoableEditListener(undoableEditListener);
 }
 public void removeUndoableEditListener(UndoableEditListener undoableEditListener) {
   undoableEditSupport.removeUndoableEditListener(undoableEditListener);
 }
 public void setPolygon(Polygon newValue) {
   polygon = newValue;
   repaint();
 }
 public Polygon getPolygon() {
   Polygon returnValue;
   if (polygon.npoints == 0) {
     returnValue = new Polygon();
   } else {
     returnValue = new Polygon(polygon.xpoints, polygon.ypoints, polygon.npoints);
   }
   return returnValue;
 }
 protected void paintComponent(Graphics g) {
   super.paintComponent(g);
   g.drawPolygon(polygon);
 }

} class UndoManagerHelper {

 public static Action getUndoAction(UndoManager manager, String label) {
   return new UndoAction(manager, label);
 }
 public static Action getUndoAction(UndoManager manager) {
   return new UndoAction(manager, (String) UIManager.get("AbstractUndoableEdit.undoText"));
 }
 public static Action getRedoAction(UndoManager manager, String label) {
   return new RedoAction(manager, label);
 }
 public static Action getRedoAction(UndoManager manager) {
   return new RedoAction(manager, (String) UIManager.get("AbstractUndoableEdit.redoText"));
 }
 private abstract static class UndoRedoAction extends AbstractAction {
   UndoManager undoManager = new UndoManager();
   String errorMessage = "Cannot undo";
   String errorTitle = "Undo Problem";
   protected UndoRedoAction(UndoManager manager, String name) {
     super(name);
     undoManager = manager;
   }
   public void setErrorMessage(String newValue) {
     errorMessage = newValue;
   }
   public void setErrorTitle(String newValue) {
     errorTitle = newValue;
   }
   protected void showMessage(Object source) {
     if (source instanceof Component) {
       JOptionPane.showMessageDialog((Component) source, errorMessage, errorTitle,
           JOptionPane.WARNING_MESSAGE);
     } else {
       System.err.println(errorMessage);
     }
   }
 }
 public static class UndoAction extends UndoRedoAction {
   public UndoAction(UndoManager manager, String name) {
     super(manager, name);
     setErrorMessage("Cannot undo");
     setErrorTitle("Undo Problem");
   }
   public void actionPerformed(ActionEvent actionEvent) {
     try {
       undoManager.undo();
     } catch (CannotUndoException cannotUndoException) {
       showMessage(actionEvent.getSource());
     }
   }
 }
 public static class RedoAction extends UndoRedoAction {
   public RedoAction(UndoManager manager, String name) {
     super(manager, name);
     setErrorMessage("Cannot redo");
     setErrorTitle("Redo Problem");
   }
   public void actionPerformed(ActionEvent actionEvent) {
     try {
       undoManager.redo();
     } catch (CannotRedoException cannotRedoException) {
       showMessage(actionEvent.getSource());
     }
   }
 }

}

      </source>
   
  
 
  

UndoableEditSupport: postEdit(UndoableEdit e)

   <source lang="java">

import java.awt.BorderLayout; import java.awt.ruponent; import java.awt.Container; import java.awt.Graphics; import java.awt.Polygon; import java.awt.event.ActionEvent; import java.awt.event.MouseAdapter; import java.awt.event.MouseEvent; import java.awt.event.MouseListener; import javax.swing.AbstractAction; import javax.swing.Action; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JOptionPane; import javax.swing.JPanel; import javax.swing.JToolBar; import javax.swing.UIManager; import javax.swing.event.UndoableEditListener; import javax.swing.undo.AbstractUndoableEdit; import javax.swing.undo.CannotRedoException; import javax.swing.undo.CannotUndoException; import javax.swing.undo.UndoManager; import javax.swing.undo.UndoableEditSupport; public class UndoDrawing {

 public static void main(String args[]) {
   JFrame frame = new JFrame("Drawing Sample");
   frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   UndoableDrawingPanel drawingPanel = new UndoableDrawingPanel();
   UndoManager manager = new UndoManager();
   drawingPanel.addUndoableEditListener(manager);
   JToolBar toolbar = new JToolBar();
   JButton undoButton = new JButton(UndoManagerHelper.getUndoAction(manager));
   toolbar.add(undoButton);
   JButton redoButton = new JButton(UndoManagerHelper.getRedoAction(manager));
   toolbar.add(redoButton);
   Container content = frame.getContentPane();
   content.add(toolbar, BorderLayout.NORTH);
   content.add(drawingPanel, BorderLayout.CENTER);
   frame.setSize(300, 150);
   frame.setVisible(true);
 }

} class UndoableDrawEdit extends AbstractUndoableEdit {

 UndoableDrawingPanel panel;
 Polygon polygon, savedPolygon;
 public UndoableDrawEdit(UndoableDrawingPanel panel) {
   this.panel = panel;
   polygon = panel.getPolygon();
 }
 public String getPresentationName() {
   return "Polygon of size " + polygon.npoints;
 }
 public void redo() throws CannotRedoException {
   super.redo();
   if (savedPolygon == null) {
     // Should never get here, as super() doesn"t permit redoing
     throw new CannotRedoException();
   } else {
     panel.setPolygon(savedPolygon);
     savedPolygon = null;
   }
 }
 public void undo() throws CannotUndoException {
   super.undo();
   savedPolygon = panel.getPolygon();
   panel.setPolygon(polygon);
 }

} class UndoableDrawingPanel extends JPanel {

 UndoableEditSupport undoableEditSupport = new UndoableEditSupport(this);
 Polygon polygon = new Polygon();
 public UndoableDrawingPanel() {
   MouseListener mouseListener = new MouseAdapter() {
     public void mouseReleased(MouseEvent mouseEvent) {
       undoableEditSupport.postEdit(new UndoableDrawEdit(UndoableDrawingPanel.this));
       polygon.addPoint(mouseEvent.getX(), mouseEvent.getY());
       repaint();
     }
   };
   addMouseListener(mouseListener);
 }
 public void addUndoableEditListener(UndoableEditListener undoableEditListener) {
   undoableEditSupport.addUndoableEditListener(undoableEditListener);
 }
 public void removeUndoableEditListener(UndoableEditListener undoableEditListener) {
   undoableEditSupport.removeUndoableEditListener(undoableEditListener);
 }
 public void setPolygon(Polygon newValue) {
   polygon = newValue;
   repaint();
 }
 public Polygon getPolygon() {
   Polygon returnValue;
   if (polygon.npoints == 0) {
     returnValue = new Polygon();
   } else {
     returnValue = new Polygon(polygon.xpoints, polygon.ypoints, polygon.npoints);
   }
   return returnValue;
 }
 protected void paintComponent(Graphics g) {
   super.paintComponent(g);
   g.drawPolygon(polygon);
 }

} class UndoManagerHelper {

 public static Action getUndoAction(UndoManager manager, String label) {
   return new UndoAction(manager, label);
 }
 public static Action getUndoAction(UndoManager manager) {
   return new UndoAction(manager, (String) UIManager.get("AbstractUndoableEdit.undoText"));
 }
 public static Action getRedoAction(UndoManager manager, String label) {
   return new RedoAction(manager, label);
 }
 public static Action getRedoAction(UndoManager manager) {
   return new RedoAction(manager, (String) UIManager.get("AbstractUndoableEdit.redoText"));
 }
 private abstract static class UndoRedoAction extends AbstractAction {
   UndoManager undoManager = new UndoManager();
   String errorMessage = "Cannot undo";
   String errorTitle = "Undo Problem";
   protected UndoRedoAction(UndoManager manager, String name) {
     super(name);
     undoManager = manager;
   }
   public void setErrorMessage(String newValue) {
     errorMessage = newValue;
   }
   public void setErrorTitle(String newValue) {
     errorTitle = newValue;
   }
   protected void showMessage(Object source) {
     if (source instanceof Component) {
       JOptionPane.showMessageDialog((Component) source, errorMessage, errorTitle,
           JOptionPane.WARNING_MESSAGE);
     } else {
       System.err.println(errorMessage);
     }
   }
 }
 public static class UndoAction extends UndoRedoAction {
   public UndoAction(UndoManager manager, String name) {
     super(manager, name);
     setErrorMessage("Cannot undo");
     setErrorTitle("Undo Problem");
   }
   public void actionPerformed(ActionEvent actionEvent) {
     try {
       undoManager.undo();
     } catch (CannotUndoException cannotUndoException) {
       showMessage(actionEvent.getSource());
     }
   }
 }
 public static class RedoAction extends UndoRedoAction {
   public RedoAction(UndoManager manager, String name) {
     super(manager, name);
     setErrorMessage("Cannot redo");
     setErrorTitle("Redo Problem");
   }
   public void actionPerformed(ActionEvent actionEvent) {
     try {
       undoManager.redo();
     } catch (CannotRedoException cannotRedoException) {
       showMessage(actionEvent.getSource());
     }
   }
 }

}

      </source>
   
  
 
  

UndoableEditSupport: removeUndoableEditListener(UndoableEditListener l)

   <source lang="java">

import java.awt.BorderLayout; import java.awt.ruponent; import java.awt.Container; import java.awt.Graphics; import java.awt.Polygon; import java.awt.event.ActionEvent; import java.awt.event.MouseAdapter; import java.awt.event.MouseEvent; import java.awt.event.MouseListener; import javax.swing.AbstractAction; import javax.swing.Action; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JOptionPane; import javax.swing.JPanel; import javax.swing.JToolBar; import javax.swing.UIManager; import javax.swing.event.UndoableEditListener; import javax.swing.undo.AbstractUndoableEdit; import javax.swing.undo.CannotRedoException; import javax.swing.undo.CannotUndoException; import javax.swing.undo.UndoManager; import javax.swing.undo.UndoableEditSupport; public class UndoDrawing {

 public static void main(String args[]) {
   JFrame frame = new JFrame("Drawing Sample");
   frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   UndoableDrawingPanel drawingPanel = new UndoableDrawingPanel();
   UndoManager manager = new UndoManager();
   drawingPanel.addUndoableEditListener(manager);
   JToolBar toolbar = new JToolBar();
   JButton undoButton = new JButton(UndoManagerHelper.getUndoAction(manager));
   toolbar.add(undoButton);
   JButton redoButton = new JButton(UndoManagerHelper.getRedoAction(manager));
   toolbar.add(redoButton);
   Container content = frame.getContentPane();
   content.add(toolbar, BorderLayout.NORTH);
   content.add(drawingPanel, BorderLayout.CENTER);
   frame.setSize(300, 150);
   frame.setVisible(true);
 }

} class UndoableDrawEdit extends AbstractUndoableEdit {

 UndoableDrawingPanel panel;
 Polygon polygon, savedPolygon;
 public UndoableDrawEdit(UndoableDrawingPanel panel) {
   this.panel = panel;
   polygon = panel.getPolygon();
 }
 public String getPresentationName() {
   return "Polygon of size " + polygon.npoints;
 }
 public void redo() throws CannotRedoException {
   super.redo();
   if (savedPolygon == null) {
     // Should never get here, as super() doesn"t permit redoing
     throw new CannotRedoException();
   } else {
     panel.setPolygon(savedPolygon);
     savedPolygon = null;
   }
 }
 public void undo() throws CannotUndoException {
   super.undo();
   savedPolygon = panel.getPolygon();
   panel.setPolygon(polygon);
 }

} class UndoableDrawingPanel extends JPanel {

 UndoableEditSupport undoableEditSupport = new UndoableEditSupport(this);
 Polygon polygon = new Polygon();
 public UndoableDrawingPanel() {
   MouseListener mouseListener = new MouseAdapter() {
     public void mouseReleased(MouseEvent mouseEvent) {
       undoableEditSupport.postEdit(new UndoableDrawEdit(UndoableDrawingPanel.this));
       polygon.addPoint(mouseEvent.getX(), mouseEvent.getY());
       repaint();
     }
   };
   addMouseListener(mouseListener);
 }
 public void addUndoableEditListener(UndoableEditListener undoableEditListener) {
   undoableEditSupport.addUndoableEditListener(undoableEditListener);
 }
 public void removeUndoableEditListener(UndoableEditListener undoableEditListener) {
   undoableEditSupport.removeUndoableEditListener(undoableEditListener);
 }
 public void setPolygon(Polygon newValue) {
   polygon = newValue;
   repaint();
 }
 public Polygon getPolygon() {
   Polygon returnValue;
   if (polygon.npoints == 0) {
     returnValue = new Polygon();
   } else {
     returnValue = new Polygon(polygon.xpoints, polygon.ypoints, polygon.npoints);
   }
   return returnValue;
 }
 protected void paintComponent(Graphics g) {
   super.paintComponent(g);
   g.drawPolygon(polygon);
 }

} class UndoManagerHelper {

 public static Action getUndoAction(UndoManager manager, String label) {
   return new UndoAction(manager, label);
 }
 public static Action getUndoAction(UndoManager manager) {
   return new UndoAction(manager, (String) UIManager.get("AbstractUndoableEdit.undoText"));
 }
 public static Action getRedoAction(UndoManager manager, String label) {
   return new RedoAction(manager, label);
 }
 public static Action getRedoAction(UndoManager manager) {
   return new RedoAction(manager, (String) UIManager.get("AbstractUndoableEdit.redoText"));
 }
 private abstract static class UndoRedoAction extends AbstractAction {
   UndoManager undoManager = new UndoManager();
   String errorMessage = "Cannot undo";
   String errorTitle = "Undo Problem";
   protected UndoRedoAction(UndoManager manager, String name) {
     super(name);
     undoManager = manager;
   }
   public void setErrorMessage(String newValue) {
     errorMessage = newValue;
   }
   public void setErrorTitle(String newValue) {
     errorTitle = newValue;
   }
   protected void showMessage(Object source) {
     if (source instanceof Component) {
       JOptionPane.showMessageDialog((Component) source, errorMessage, errorTitle,
           JOptionPane.WARNING_MESSAGE);
     } else {
       System.err.println(errorMessage);
     }
   }
 }
 public static class UndoAction extends UndoRedoAction {
   public UndoAction(UndoManager manager, String name) {
     super(manager, name);
     setErrorMessage("Cannot undo");
     setErrorTitle("Undo Problem");
   }
   public void actionPerformed(ActionEvent actionEvent) {
     try {
       undoManager.undo();
     } catch (CannotUndoException cannotUndoException) {
       showMessage(actionEvent.getSource());
     }
   }
 }
 public static class RedoAction extends UndoRedoAction {
   public RedoAction(UndoManager manager, String name) {
     super(manager, name);
     setErrorMessage("Cannot redo");
     setErrorTitle("Redo Problem");
   }
   public void actionPerformed(ActionEvent actionEvent) {
     try {
       undoManager.redo();
     } catch (CannotRedoException cannotRedoException) {
       showMessage(actionEvent.getSource());
     }
   }
 }

}

      </source>