Java by API/javax.swing.undo/UndoManager
Содержание
- 1 new UndoManager()
- 2 UndoManager: addEdit(UndoableEdit anEdit)
- 3 UndoManager: canRedo()
- 4 UndoManager: canUndo()
- 5 UndoManager: discardAllEdits()
- 6 UndoManager: end()
- 7 UndoManager: getRedoPresentationName()
- 8 UndoManager: getUndoPresentationName()
- 9 UndoManager: redo()
- 10 UndoManager: setLimit(int l)
- 11 UndoManager: undo()
- 12 UndoManager: undoOrRedo()
new UndoManager()
<source lang="java">
import java.awt.BorderLayout; import java.awt.ruponent; import java.awt.Container; import java.awt.event.ActionEvent; import javax.swing.AbstractAction; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JOptionPane; import javax.swing.JScrollPane; import javax.swing.JTextArea; import javax.swing.JToolBar; import javax.swing.UIManager; import javax.swing.undo.CannotUndoException; import javax.swing.undo.UndoManager; public class MainClass {
public static void main(final String args[]) { JFrame frame = new JFrame("Undo Sample"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); JTextArea textArea = new JTextArea(); JScrollPane scrollPane = new JScrollPane(textArea); UndoManager manager = new UndoManager(); textArea.getDocument().addUndoableEditListener(manager); JToolBar toolbar = new JToolBar(); JButton undoButton = new JButton(new UndoAction(manager, (String) UIManager .get("AbstractUndoableEdit.undoText"))); toolbar.add(undoButton); Container content = frame.getContentPane(); content.add(toolbar, BorderLayout.NORTH); content.add(scrollPane, BorderLayout.CENTER); frame.setSize(300, 150); frame.setVisible(true); }
} abstract 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); } }
} 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()); } }
}
</source>
UndoManager: addEdit(UndoableEdit anEdit)
<source lang="java">
import java.util.Enumeration; import java.util.Vector; import javax.swing.undo.AbstractUndoableEdit; import javax.swing.undo.CannotRedoException; import javax.swing.undo.CannotUndoException; import javax.swing.undo.UndoManager; import javax.swing.undo.UndoableEdit; public class UndoManagerDetails {
public static void main(String[] args) { UndoManager mgr = new UndoManager(); mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); mgr.addEdit(new SampleUndoableEdit(2, false, true, false)); mgr.addEdit(new SampleUndoableEdit(3, false, false, false)); mgr.addEdit(new SampleUndoableEdit(4, false, false, false)); System.out.println("Insignificant edit example"); mgr.undo(); mgr.redo(); System.out.println(mgr.canRedo()); // No more sig. edits // Show how edits that call add/replace are used. // // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(5, true, true, false)); mgr.addEdit(new SampleUndoableEdit(6, false, true, false)); System.out.println("Absorbed (by addEdit) edit example"); mgr.undo(); mgr.discardAllEdits(); // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); mgr.addEdit(new SampleUndoableEdit(2, false, true, true)); System.out.println("Absorbed (by replaceEdit) edit example"); mgr.undo(); System.out.println(mgr.canUndo()); // Show how changing limit works. mgr.discardAllEdits(); // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); mgr.addEdit(new SampleUndoableEdit(2, false, true, false)); mgr.addEdit(new SampleUndoableEdit(3, false, true, false)); mgr.addEdit(new SampleUndoableEdit(4, false, true, false)); mgr.addEdit(new SampleUndoableEdit(5, false, true, false)); mgr.addEdit(new SampleUndoableEdit(6, false, true, false)); System.out.println("Changing limit example"); mgr.undo(); mgr.undo(); mgr.undo(); // Now 3 undoable, 3 redoable mgr.setLimit(4); // Now 2 undoable, 2 redoable! while (mgr.canUndo()) mgr.undo(); while (mgr.canRedo()) mgr.redo(); // undoOrRedo example mgr.discardAllEdits(); mgr.setLimit(1); // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); System.out.println("undoOrRedo example"); System.out.println(mgr.getUndoOrRedoPresentationName()); mgr.undoOrRedo(); System.out.println(mgr.getUndoOrRedoPresentationName()); mgr.undoOrRedo(); // Show how UndoManager becomes a CompositeEdit. mgr.discardAllEdits(); mgr.setLimit(100); // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); mgr.addEdit(new SampleUndoableEdit(2, false, true, false)); mgr.addEdit(new SampleUndoableEdit(3, false, true, false)); System.out.println("Transform to composite example"); mgr.end(); mgr.undo(); mgr.redo(); // Show that adds are no longer allowed. Note that addEdit() returns true in // pre-JDK 1.2 Swing releases. This is fixed in JDK 1.2. System.out.println(mgr.addEdit(new SampleUndoableEdit(4, false, true, false))); mgr.undo(); // note that edit 4 is not there }
} class SampleUndoableEdit extends AbstractUndoableEdit {
private boolean isSignificant; private boolean isReplacer; private int number; private boolean allowAdds; private Vector addedEdits; private UndoableEdit replaced; // Create a new edit with an identifying number. The boolean arguments define // the edit"s behavior. public SampleUndoableEdit(int number, boolean allowAdds, boolean isSignificant, boolean isReplacer) { this.number = number; this.allowAdds = allowAdds; if (allowAdds) addedEdits = new Vector(); this.isSignificant = isSignificant; this.isReplacer = isReplacer; } // "Undo" the edit by printing a message to the screen. public void undo() throws CannotUndoException { super.undo(); System.out.print("Undo " + number); dumpState(); } // "Redo" the edit by printing a message to the screen. public void redo() throws CannotRedoException { super.redo(); System.out.print("Redo " + number); dumpState(); } // If allowAdds is true, we store the input edit. If not, just return false. public boolean addEdit(UndoableEdit anEdit) { if (allowAdds) { addedEdits.addElement(anEdit); return true; } else return false; } // If isReplacer is true, we store the edit we are replacing. public boolean replaceEdit(UndoableEdit anEdit) { if (isReplacer) { replaced = anEdit; return true; } else return false; } // Significance is based on constructor parameter. public boolean isSignificant() { return isSignificant; } // Just return our identifier. public String toString() { return "<" + number + ">"; } // Debug output. public void dumpState() { if (allowAdds && addedEdits.size() > 0) { Enumeration e = addedEdits.elements(); System.out.print(" (absorbed: "); while (e.hasMoreElements()) { System.out.print(e.nextElement()); } System.out.print(")"); } if (isReplacer && replaced != null) { System.out.print(" (replaced: " + replaced + ")"); } System.out.println(); }
}
</source>
UndoManager: canRedo()
<source lang="java">
import java.util.Enumeration; import java.util.Vector; import javax.swing.undo.AbstractUndoableEdit; import javax.swing.undo.CannotRedoException; import javax.swing.undo.CannotUndoException; import javax.swing.undo.UndoManager; import javax.swing.undo.UndoableEdit; public class UndoManagerDetails {
public static void main(String[] args) { UndoManager mgr = new UndoManager(); mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); mgr.addEdit(new SampleUndoableEdit(2, false, true, false)); mgr.addEdit(new SampleUndoableEdit(3, false, false, false)); mgr.addEdit(new SampleUndoableEdit(4, false, false, false)); System.out.println("Insignificant edit example"); mgr.undo(); mgr.redo(); System.out.println(mgr.canRedo()); // No more sig. edits // Show how edits that call add/replace are used. // // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(5, true, true, false)); mgr.addEdit(new SampleUndoableEdit(6, false, true, false)); System.out.println("Absorbed (by addEdit) edit example"); mgr.undo(); mgr.discardAllEdits(); // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); mgr.addEdit(new SampleUndoableEdit(2, false, true, true)); System.out.println("Absorbed (by replaceEdit) edit example"); mgr.undo(); System.out.println(mgr.canUndo()); // Show how changing limit works. mgr.discardAllEdits(); // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); mgr.addEdit(new SampleUndoableEdit(2, false, true, false)); mgr.addEdit(new SampleUndoableEdit(3, false, true, false)); mgr.addEdit(new SampleUndoableEdit(4, false, true, false)); mgr.addEdit(new SampleUndoableEdit(5, false, true, false)); mgr.addEdit(new SampleUndoableEdit(6, false, true, false)); System.out.println("Changing limit example"); mgr.undo(); mgr.undo(); mgr.undo(); // Now 3 undoable, 3 redoable mgr.setLimit(4); // Now 2 undoable, 2 redoable! while (mgr.canUndo()) mgr.undo(); while (mgr.canRedo()) mgr.redo(); // undoOrRedo example mgr.discardAllEdits(); mgr.setLimit(1); // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); System.out.println("undoOrRedo example"); System.out.println(mgr.getUndoOrRedoPresentationName()); mgr.undoOrRedo(); System.out.println(mgr.getUndoOrRedoPresentationName()); mgr.undoOrRedo(); // Show how UndoManager becomes a CompositeEdit. mgr.discardAllEdits(); mgr.setLimit(100); // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); mgr.addEdit(new SampleUndoableEdit(2, false, true, false)); mgr.addEdit(new SampleUndoableEdit(3, false, true, false)); System.out.println("Transform to composite example"); mgr.end(); mgr.undo(); mgr.redo(); // Show that adds are no longer allowed. Note that addEdit() returns true in // pre-JDK 1.2 Swing releases. This is fixed in JDK 1.2. System.out.println(mgr.addEdit(new SampleUndoableEdit(4, false, true, false))); mgr.undo(); // note that edit 4 is not there }
} class SampleUndoableEdit extends AbstractUndoableEdit {
private boolean isSignificant; private boolean isReplacer; private int number; private boolean allowAdds; private Vector addedEdits; private UndoableEdit replaced; // Create a new edit with an identifying number. The boolean arguments define // the edit"s behavior. public SampleUndoableEdit(int number, boolean allowAdds, boolean isSignificant, boolean isReplacer) { this.number = number; this.allowAdds = allowAdds; if (allowAdds) addedEdits = new Vector(); this.isSignificant = isSignificant; this.isReplacer = isReplacer; } // "Undo" the edit by printing a message to the screen. public void undo() throws CannotUndoException { super.undo(); System.out.print("Undo " + number); dumpState(); } // "Redo" the edit by printing a message to the screen. public void redo() throws CannotRedoException { super.redo(); System.out.print("Redo " + number); dumpState(); } // If allowAdds is true, we store the input edit. If not, just return false. public boolean addEdit(UndoableEdit anEdit) { if (allowAdds) { addedEdits.addElement(anEdit); return true; } else return false; } // If isReplacer is true, we store the edit we are replacing. public boolean replaceEdit(UndoableEdit anEdit) { if (isReplacer) { replaced = anEdit; return true; } else return false; } // Significance is based on constructor parameter. public boolean isSignificant() { return isSignificant; } // Just return our identifier. public String toString() { return "<" + number + ">"; } // Debug output. public void dumpState() { if (allowAdds && addedEdits.size() > 0) { Enumeration e = addedEdits.elements(); System.out.print(" (absorbed: "); while (e.hasMoreElements()) { System.out.print(e.nextElement()); } System.out.print(")"); } if (isReplacer && replaced != null) { System.out.print(" (replaced: " + replaced + ")"); } System.out.println(); }
}
</source>
UndoManager: canUndo()
<source lang="java">
import java.util.Enumeration; import java.util.Vector; import javax.swing.undo.AbstractUndoableEdit; import javax.swing.undo.CannotRedoException; import javax.swing.undo.CannotUndoException; import javax.swing.undo.UndoManager; import javax.swing.undo.UndoableEdit; public class UndoManagerDetails {
public static void main(String[] args) { UndoManager mgr = new UndoManager(); mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); mgr.addEdit(new SampleUndoableEdit(2, false, true, false)); mgr.addEdit(new SampleUndoableEdit(3, false, false, false)); mgr.addEdit(new SampleUndoableEdit(4, false, false, false)); System.out.println("Insignificant edit example"); mgr.undo(); mgr.redo(); System.out.println(mgr.canRedo()); // No more sig. edits // Show how edits that call add/replace are used. // // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(5, true, true, false)); mgr.addEdit(new SampleUndoableEdit(6, false, true, false)); System.out.println("Absorbed (by addEdit) edit example"); mgr.undo(); mgr.discardAllEdits(); // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); mgr.addEdit(new SampleUndoableEdit(2, false, true, true)); System.out.println("Absorbed (by replaceEdit) edit example"); mgr.undo(); System.out.println(mgr.canUndo()); // Show how changing limit works. mgr.discardAllEdits(); // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); mgr.addEdit(new SampleUndoableEdit(2, false, true, false)); mgr.addEdit(new SampleUndoableEdit(3, false, true, false)); mgr.addEdit(new SampleUndoableEdit(4, false, true, false)); mgr.addEdit(new SampleUndoableEdit(5, false, true, false)); mgr.addEdit(new SampleUndoableEdit(6, false, true, false)); System.out.println("Changing limit example"); mgr.undo(); mgr.undo(); mgr.undo(); // Now 3 undoable, 3 redoable mgr.setLimit(4); // Now 2 undoable, 2 redoable! while (mgr.canUndo()) mgr.undo(); while (mgr.canRedo()) mgr.redo(); // undoOrRedo example mgr.discardAllEdits(); mgr.setLimit(1); // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); System.out.println("undoOrRedo example"); System.out.println(mgr.getUndoOrRedoPresentationName()); mgr.undoOrRedo(); System.out.println(mgr.getUndoOrRedoPresentationName()); mgr.undoOrRedo(); // Show how UndoManager becomes a CompositeEdit. mgr.discardAllEdits(); mgr.setLimit(100); // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); mgr.addEdit(new SampleUndoableEdit(2, false, true, false)); mgr.addEdit(new SampleUndoableEdit(3, false, true, false)); System.out.println("Transform to composite example"); mgr.end(); mgr.undo(); mgr.redo(); // Show that adds are no longer allowed. Note that addEdit() returns true in // pre-JDK 1.2 Swing releases. This is fixed in JDK 1.2. System.out.println(mgr.addEdit(new SampleUndoableEdit(4, false, true, false))); mgr.undo(); // note that edit 4 is not there }
} class SampleUndoableEdit extends AbstractUndoableEdit {
private boolean isSignificant; private boolean isReplacer; private int number; private boolean allowAdds; private Vector addedEdits; private UndoableEdit replaced; // Create a new edit with an identifying number. The boolean arguments define // the edit"s behavior. public SampleUndoableEdit(int number, boolean allowAdds, boolean isSignificant, boolean isReplacer) { this.number = number; this.allowAdds = allowAdds; if (allowAdds) addedEdits = new Vector(); this.isSignificant = isSignificant; this.isReplacer = isReplacer; } // "Undo" the edit by printing a message to the screen. public void undo() throws CannotUndoException { super.undo(); System.out.print("Undo " + number); dumpState(); } // "Redo" the edit by printing a message to the screen. public void redo() throws CannotRedoException { super.redo(); System.out.print("Redo " + number); dumpState(); } // If allowAdds is true, we store the input edit. If not, just return false. public boolean addEdit(UndoableEdit anEdit) { if (allowAdds) { addedEdits.addElement(anEdit); return true; } else return false; } // If isReplacer is true, we store the edit we are replacing. public boolean replaceEdit(UndoableEdit anEdit) { if (isReplacer) { replaced = anEdit; return true; } else return false; } // Significance is based on constructor parameter. public boolean isSignificant() { return isSignificant; } // Just return our identifier. public String toString() { return "<" + number + ">"; } // Debug output. public void dumpState() { if (allowAdds && addedEdits.size() > 0) { Enumeration e = addedEdits.elements(); System.out.print(" (absorbed: "); while (e.hasMoreElements()) { System.out.print(e.nextElement()); } System.out.print(")"); } if (isReplacer && replaced != null) { System.out.print(" (replaced: " + replaced + ")"); } System.out.println(); }
}
</source>
UndoManager: discardAllEdits()
<source lang="java">
import java.util.Enumeration; import java.util.Vector; import javax.swing.undo.AbstractUndoableEdit; import javax.swing.undo.CannotRedoException; import javax.swing.undo.CannotUndoException; import javax.swing.undo.UndoManager; import javax.swing.undo.UndoableEdit; public class UndoManagerDetails {
public static void main(String[] args) { UndoManager mgr = new UndoManager(); mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); mgr.addEdit(new SampleUndoableEdit(2, false, true, false)); mgr.addEdit(new SampleUndoableEdit(3, false, false, false)); mgr.addEdit(new SampleUndoableEdit(4, false, false, false)); System.out.println("Insignificant edit example"); mgr.undo(); mgr.redo(); System.out.println(mgr.canRedo()); // No more sig. edits // Show how edits that call add/replace are used. // // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(5, true, true, false)); mgr.addEdit(new SampleUndoableEdit(6, false, true, false)); System.out.println("Absorbed (by addEdit) edit example"); mgr.undo(); mgr.discardAllEdits(); // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); mgr.addEdit(new SampleUndoableEdit(2, false, true, true)); System.out.println("Absorbed (by replaceEdit) edit example"); mgr.undo(); System.out.println(mgr.canUndo()); // Show how changing limit works. mgr.discardAllEdits(); // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); mgr.addEdit(new SampleUndoableEdit(2, false, true, false)); mgr.addEdit(new SampleUndoableEdit(3, false, true, false)); mgr.addEdit(new SampleUndoableEdit(4, false, true, false)); mgr.addEdit(new SampleUndoableEdit(5, false, true, false)); mgr.addEdit(new SampleUndoableEdit(6, false, true, false)); System.out.println("Changing limit example"); mgr.undo(); mgr.undo(); mgr.undo(); // Now 3 undoable, 3 redoable mgr.setLimit(4); // Now 2 undoable, 2 redoable! while (mgr.canUndo()) mgr.undo(); while (mgr.canRedo()) mgr.redo(); // undoOrRedo example mgr.discardAllEdits(); mgr.setLimit(1); // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); System.out.println("undoOrRedo example"); System.out.println(mgr.getUndoOrRedoPresentationName()); mgr.undoOrRedo(); System.out.println(mgr.getUndoOrRedoPresentationName()); mgr.undoOrRedo(); // Show how UndoManager becomes a CompositeEdit. mgr.discardAllEdits(); mgr.setLimit(100); // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); mgr.addEdit(new SampleUndoableEdit(2, false, true, false)); mgr.addEdit(new SampleUndoableEdit(3, false, true, false)); System.out.println("Transform to composite example"); mgr.end(); mgr.undo(); mgr.redo(); // Show that adds are no longer allowed. Note that addEdit() returns true in // pre-JDK 1.2 Swing releases. This is fixed in JDK 1.2. System.out.println(mgr.addEdit(new SampleUndoableEdit(4, false, true, false))); mgr.undo(); // note that edit 4 is not there }
} class SampleUndoableEdit extends AbstractUndoableEdit {
private boolean isSignificant; private boolean isReplacer; private int number; private boolean allowAdds; private Vector addedEdits; private UndoableEdit replaced; // Create a new edit with an identifying number. The boolean arguments define // the edit"s behavior. public SampleUndoableEdit(int number, boolean allowAdds, boolean isSignificant, boolean isReplacer) { this.number = number; this.allowAdds = allowAdds; if (allowAdds) addedEdits = new Vector(); this.isSignificant = isSignificant; this.isReplacer = isReplacer; } // "Undo" the edit by printing a message to the screen. public void undo() throws CannotUndoException { super.undo(); System.out.print("Undo " + number); dumpState(); } // "Redo" the edit by printing a message to the screen. public void redo() throws CannotRedoException { super.redo(); System.out.print("Redo " + number); dumpState(); } // If allowAdds is true, we store the input edit. If not, just return false. public boolean addEdit(UndoableEdit anEdit) { if (allowAdds) { addedEdits.addElement(anEdit); return true; } else return false; } // If isReplacer is true, we store the edit we are replacing. public boolean replaceEdit(UndoableEdit anEdit) { if (isReplacer) { replaced = anEdit; return true; } else return false; } // Significance is based on constructor parameter. public boolean isSignificant() { return isSignificant; } // Just return our identifier. public String toString() { return "<" + number + ">"; } // Debug output. public void dumpState() { if (allowAdds && addedEdits.size() > 0) { Enumeration e = addedEdits.elements(); System.out.print(" (absorbed: "); while (e.hasMoreElements()) { System.out.print(e.nextElement()); } System.out.print(")"); } if (isReplacer && replaced != null) { System.out.print(" (replaced: " + replaced + ")"); } System.out.println(); }
}
</source>
UndoManager: end()
<source lang="java">
import java.util.Enumeration; import java.util.Vector; import javax.swing.undo.AbstractUndoableEdit; import javax.swing.undo.CannotRedoException; import javax.swing.undo.CannotUndoException; import javax.swing.undo.UndoManager; import javax.swing.undo.UndoableEdit; public class UndoManagerDetails {
public static void main(String[] args) { UndoManager mgr = new UndoManager(); mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); mgr.addEdit(new SampleUndoableEdit(2, false, true, false)); mgr.addEdit(new SampleUndoableEdit(3, false, false, false)); mgr.addEdit(new SampleUndoableEdit(4, false, false, false)); System.out.println("Insignificant edit example"); mgr.undo(); mgr.redo(); System.out.println(mgr.canRedo()); // No more sig. edits // Show how edits that call add/replace are used. // // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(5, true, true, false)); mgr.addEdit(new SampleUndoableEdit(6, false, true, false)); System.out.println("Absorbed (by addEdit) edit example"); mgr.undo(); mgr.discardAllEdits(); // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); mgr.addEdit(new SampleUndoableEdit(2, false, true, true)); System.out.println("Absorbed (by replaceEdit) edit example"); mgr.undo(); System.out.println(mgr.canUndo()); // Show how changing limit works. mgr.discardAllEdits(); // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); mgr.addEdit(new SampleUndoableEdit(2, false, true, false)); mgr.addEdit(new SampleUndoableEdit(3, false, true, false)); mgr.addEdit(new SampleUndoableEdit(4, false, true, false)); mgr.addEdit(new SampleUndoableEdit(5, false, true, false)); mgr.addEdit(new SampleUndoableEdit(6, false, true, false)); System.out.println("Changing limit example"); mgr.undo(); mgr.undo(); mgr.undo(); // Now 3 undoable, 3 redoable mgr.setLimit(4); // Now 2 undoable, 2 redoable! while (mgr.canUndo()) mgr.undo(); while (mgr.canRedo()) mgr.redo(); // undoOrRedo example mgr.discardAllEdits(); mgr.setLimit(1); // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); System.out.println("undoOrRedo example"); System.out.println(mgr.getUndoOrRedoPresentationName()); mgr.undoOrRedo(); System.out.println(mgr.getUndoOrRedoPresentationName()); mgr.undoOrRedo(); // Show how UndoManager becomes a CompositeEdit. mgr.discardAllEdits(); mgr.setLimit(100); // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); mgr.addEdit(new SampleUndoableEdit(2, false, true, false)); mgr.addEdit(new SampleUndoableEdit(3, false, true, false)); System.out.println("Transform to composite example"); mgr.end(); mgr.undo(); mgr.redo(); // Show that adds are no longer allowed. Note that addEdit() returns true in // pre-JDK 1.2 Swing releases. This is fixed in JDK 1.2. System.out.println(mgr.addEdit(new SampleUndoableEdit(4, false, true, false))); mgr.undo(); // note that edit 4 is not there }
} class SampleUndoableEdit extends AbstractUndoableEdit {
private boolean isSignificant; private boolean isReplacer; private int number; private boolean allowAdds; private Vector addedEdits; private UndoableEdit replaced; // Create a new edit with an identifying number. The boolean arguments define // the edit"s behavior. public SampleUndoableEdit(int number, boolean allowAdds, boolean isSignificant, boolean isReplacer) { this.number = number; this.allowAdds = allowAdds; if (allowAdds) addedEdits = new Vector(); this.isSignificant = isSignificant; this.isReplacer = isReplacer; } // "Undo" the edit by printing a message to the screen. public void undo() throws CannotUndoException { super.undo(); System.out.print("Undo " + number); dumpState(); } // "Redo" the edit by printing a message to the screen. public void redo() throws CannotRedoException { super.redo(); System.out.print("Redo " + number); dumpState(); } // If allowAdds is true, we store the input edit. If not, just return false. public boolean addEdit(UndoableEdit anEdit) { if (allowAdds) { addedEdits.addElement(anEdit); return true; } else return false; } // If isReplacer is true, we store the edit we are replacing. public boolean replaceEdit(UndoableEdit anEdit) { if (isReplacer) { replaced = anEdit; return true; } else return false; } // Significance is based on constructor parameter. public boolean isSignificant() { return isSignificant; } // Just return our identifier. public String toString() { return "<" + number + ">"; } // Debug output. public void dumpState() { if (allowAdds && addedEdits.size() > 0) { Enumeration e = addedEdits.elements(); System.out.print(" (absorbed: "); while (e.hasMoreElements()) { System.out.print(e.nextElement()); } System.out.print(")"); } if (isReplacer && replaced != null) { System.out.print(" (replaced: " + replaced + ")"); } System.out.println(); }
}
</source>
UndoManager: getRedoPresentationName()
<source lang="java">
import java.awt.BorderLayout; import java.awt.GridLayout; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JPanel; import javax.swing.JScrollPane; import javax.swing.JTextArea; import javax.swing.event.UndoableEditEvent; import javax.swing.event.UndoableEditListener; import javax.swing.undo.CannotRedoException; import javax.swing.undo.UndoManager; public class Main extends JFrame {
protected JTextArea textArea = new JTextArea(); protected UndoManager undoManager = new UndoManager(); protected JButton undoButton = new JButton("Undo"); protected JButton redoButton = new JButton("Redo"); public Main() { super("Undo/Redo Demo"); undoButton.setEnabled(false); redoButton.setEnabled(false); JPanel buttonPanel = new JPanel(new GridLayout()); buttonPanel.add(undoButton); buttonPanel.add(redoButton); JScrollPane scroller = new JScrollPane(textArea); getContentPane().add(buttonPanel, BorderLayout.NORTH); getContentPane().add(scroller, BorderLayout.CENTER); textArea.getDocument().addUndoableEditListener( new UndoableEditListener() { public void undoableEditHappened(UndoableEditEvent e) { undoManager.addEdit(e.getEdit()); updateButtons(); } }); undoButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { try { undoManager.undo(); } catch (CannotRedoException cre) { cre.printStackTrace(); } updateButtons(); } }); redoButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { try { undoManager.redo(); } catch (CannotRedoException cre) { cre.printStackTrace(); } updateButtons(); } }); setSize(400, 300); setVisible(true); } public void updateButtons() { undoButton.setText(undoManager.getUndoPresentationName()); redoButton.setText(undoManager.getRedoPresentationName()); undoButton.setEnabled(undoManager.canUndo()); redoButton.setEnabled(undoManager.canRedo()); } public static void main(String argv[]) { new Main(); }
}
</source>
UndoManager: getUndoPresentationName()
<source lang="java">
import java.awt.BorderLayout; import java.awt.GridLayout; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JPanel; import javax.swing.JScrollPane; import javax.swing.JTextArea; import javax.swing.event.UndoableEditEvent; import javax.swing.event.UndoableEditListener; import javax.swing.undo.CannotRedoException; import javax.swing.undo.UndoManager; public class Main extends JFrame {
protected JTextArea textArea = new JTextArea(); protected UndoManager undoManager = new UndoManager(); protected JButton undoButton = new JButton("Undo"); protected JButton redoButton = new JButton("Redo"); public Main() { super("Undo/Redo Demo"); undoButton.setEnabled(false); redoButton.setEnabled(false); JPanel buttonPanel = new JPanel(new GridLayout()); buttonPanel.add(undoButton); buttonPanel.add(redoButton); JScrollPane scroller = new JScrollPane(textArea); getContentPane().add(buttonPanel, BorderLayout.NORTH); getContentPane().add(scroller, BorderLayout.CENTER); textArea.getDocument().addUndoableEditListener( new UndoableEditListener() { public void undoableEditHappened(UndoableEditEvent e) { undoManager.addEdit(e.getEdit()); updateButtons(); } }); undoButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { try { undoManager.undo(); } catch (CannotRedoException cre) { cre.printStackTrace(); } updateButtons(); } }); redoButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { try { undoManager.redo(); } catch (CannotRedoException cre) { cre.printStackTrace(); } updateButtons(); } }); setSize(400, 300); setVisible(true); } public void updateButtons() { undoButton.setText(undoManager.getUndoPresentationName()); redoButton.setText(undoManager.getRedoPresentationName()); undoButton.setEnabled(undoManager.canUndo()); redoButton.setEnabled(undoManager.canRedo()); } public static void main(String argv[]) { new Main(); }
}
</source>
UndoManager: redo()
<source lang="java">
import java.awt.BorderLayout; import java.awt.ruponent; import java.awt.Container; import java.awt.event.ActionEvent; import javax.swing.AbstractAction; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JOptionPane; import javax.swing.JScrollPane; import javax.swing.JTextArea; import javax.swing.JToolBar; import javax.swing.UIManager; import javax.swing.undo.CannotRedoException; import javax.swing.undo.CannotUndoException; import javax.swing.undo.UndoManager; public class MainClass {
public static void main(final String args[]) { JFrame frame = new JFrame("Undo Sample"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); JTextArea textArea = new JTextArea(); JScrollPane scrollPane = new JScrollPane(textArea); UndoManager manager = new UndoManager(); textArea.getDocument().addUndoableEditListener(manager); JToolBar toolbar = new JToolBar(); JButton undoButton = new JButton(new UndoAction(manager, (String) UIManager .get("AbstractUndoableEdit.undoText"))); toolbar.add(undoButton); JButton redoButton = new JButton(new RedoAction(manager, (String) UIManager .get("AbstractUndoableEdit.redoText"))); toolbar.add(redoButton); Container content = frame.getContentPane(); content.add(toolbar, BorderLayout.NORTH); content.add(scrollPane, BorderLayout.CENTER); frame.setSize(300, 150); frame.setVisible(true); }
} abstract 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); } }
} 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()); } }
} 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>
UndoManager: setLimit(int l)
<source lang="java">
import java.util.Enumeration; import java.util.Vector; import javax.swing.undo.AbstractUndoableEdit; import javax.swing.undo.CannotRedoException; import javax.swing.undo.CannotUndoException; import javax.swing.undo.UndoManager; import javax.swing.undo.UndoableEdit; public class UndoManagerDetails {
public static void main(String[] args) { UndoManager mgr = new UndoManager(); mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); mgr.addEdit(new SampleUndoableEdit(2, false, true, false)); mgr.addEdit(new SampleUndoableEdit(3, false, false, false)); mgr.addEdit(new SampleUndoableEdit(4, false, false, false)); System.out.println("Insignificant edit example"); mgr.undo(); mgr.redo(); System.out.println(mgr.canRedo()); // No more sig. edits // Show how edits that call add/replace are used. // // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(5, true, true, false)); mgr.addEdit(new SampleUndoableEdit(6, false, true, false)); System.out.println("Absorbed (by addEdit) edit example"); mgr.undo(); mgr.discardAllEdits(); // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); mgr.addEdit(new SampleUndoableEdit(2, false, true, true)); System.out.println("Absorbed (by replaceEdit) edit example"); mgr.undo(); System.out.println(mgr.canUndo()); // Show how changing limit works. mgr.discardAllEdits(); // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); mgr.addEdit(new SampleUndoableEdit(2, false, true, false)); mgr.addEdit(new SampleUndoableEdit(3, false, true, false)); mgr.addEdit(new SampleUndoableEdit(4, false, true, false)); mgr.addEdit(new SampleUndoableEdit(5, false, true, false)); mgr.addEdit(new SampleUndoableEdit(6, false, true, false)); System.out.println("Changing limit example"); mgr.undo(); mgr.undo(); mgr.undo(); // Now 3 undoable, 3 redoable mgr.setLimit(4); // Now 2 undoable, 2 redoable! while (mgr.canUndo()) mgr.undo(); while (mgr.canRedo()) mgr.redo(); // undoOrRedo example mgr.discardAllEdits(); mgr.setLimit(1); // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); System.out.println("undoOrRedo example"); System.out.println(mgr.getUndoOrRedoPresentationName()); mgr.undoOrRedo(); System.out.println(mgr.getUndoOrRedoPresentationName()); mgr.undoOrRedo(); // Show how UndoManager becomes a CompositeEdit. mgr.discardAllEdits(); mgr.setLimit(100); // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); mgr.addEdit(new SampleUndoableEdit(2, false, true, false)); mgr.addEdit(new SampleUndoableEdit(3, false, true, false)); System.out.println("Transform to composite example"); mgr.end(); mgr.undo(); mgr.redo(); // Show that adds are no longer allowed. Note that addEdit() returns true in // pre-JDK 1.2 Swing releases. This is fixed in JDK 1.2. System.out.println(mgr.addEdit(new SampleUndoableEdit(4, false, true, false))); mgr.undo(); // note that edit 4 is not there }
} class SampleUndoableEdit extends AbstractUndoableEdit {
private boolean isSignificant; private boolean isReplacer; private int number; private boolean allowAdds; private Vector addedEdits; private UndoableEdit replaced; // Create a new edit with an identifying number. The boolean arguments define // the edit"s behavior. public SampleUndoableEdit(int number, boolean allowAdds, boolean isSignificant, boolean isReplacer) { this.number = number; this.allowAdds = allowAdds; if (allowAdds) addedEdits = new Vector(); this.isSignificant = isSignificant; this.isReplacer = isReplacer; } // "Undo" the edit by printing a message to the screen. public void undo() throws CannotUndoException { super.undo(); System.out.print("Undo " + number); dumpState(); } // "Redo" the edit by printing a message to the screen. public void redo() throws CannotRedoException { super.redo(); System.out.print("Redo " + number); dumpState(); } // If allowAdds is true, we store the input edit. If not, just return false. public boolean addEdit(UndoableEdit anEdit) { if (allowAdds) { addedEdits.addElement(anEdit); return true; } else return false; } // If isReplacer is true, we store the edit we are replacing. public boolean replaceEdit(UndoableEdit anEdit) { if (isReplacer) { replaced = anEdit; return true; } else return false; } // Significance is based on constructor parameter. public boolean isSignificant() { return isSignificant; } // Just return our identifier. public String toString() { return "<" + number + ">"; } // Debug output. public void dumpState() { if (allowAdds && addedEdits.size() > 0) { Enumeration e = addedEdits.elements(); System.out.print(" (absorbed: "); while (e.hasMoreElements()) { System.out.print(e.nextElement()); } System.out.print(")"); } if (isReplacer && replaced != null) { System.out.print(" (replaced: " + replaced + ")"); } System.out.println(); }
}
</source>
UndoManager: undo()
<source lang="java">
import java.awt.BorderLayout; import java.awt.ruponent; import java.awt.Container; import java.awt.event.ActionEvent; import javax.swing.AbstractAction; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JOptionPane; import javax.swing.JScrollPane; import javax.swing.JTextArea; import javax.swing.JToolBar; import javax.swing.UIManager; import javax.swing.undo.CannotUndoException; import javax.swing.undo.UndoManager; public class MainClass {
public static void main(final String args[]) { JFrame frame = new JFrame("Undo Sample"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); JTextArea textArea = new JTextArea(); JScrollPane scrollPane = new JScrollPane(textArea); UndoManager manager = new UndoManager(); textArea.getDocument().addUndoableEditListener(manager); JToolBar toolbar = new JToolBar(); JButton undoButton = new JButton(new UndoAction(manager, (String) UIManager .get("AbstractUndoableEdit.undoText"))); toolbar.add(undoButton); Container content = frame.getContentPane(); content.add(toolbar, BorderLayout.NORTH); content.add(scrollPane, BorderLayout.CENTER); frame.setSize(300, 150); frame.setVisible(true); }
} abstract 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); } }
} 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()); } }
}
</source>
UndoManager: undoOrRedo()
<source lang="java">
import java.util.Enumeration; import java.util.Vector; import javax.swing.undo.AbstractUndoableEdit; import javax.swing.undo.CannotRedoException; import javax.swing.undo.CannotUndoException; import javax.swing.undo.UndoManager; import javax.swing.undo.UndoableEdit; public class UndoManagerDetails {
public static void main(String[] args) { UndoManager mgr = new UndoManager(); mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); mgr.addEdit(new SampleUndoableEdit(2, false, true, false)); mgr.addEdit(new SampleUndoableEdit(3, false, false, false)); mgr.addEdit(new SampleUndoableEdit(4, false, false, false)); System.out.println("Insignificant edit example"); mgr.undo(); mgr.redo(); System.out.println(mgr.canRedo()); // No more sig. edits // Show how edits that call add/replace are used. // // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(5, true, true, false)); mgr.addEdit(new SampleUndoableEdit(6, false, true, false)); System.out.println("Absorbed (by addEdit) edit example"); mgr.undo(); mgr.discardAllEdits(); // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); mgr.addEdit(new SampleUndoableEdit(2, false, true, true)); System.out.println("Absorbed (by replaceEdit) edit example"); mgr.undo(); System.out.println(mgr.canUndo()); // Show how changing limit works. mgr.discardAllEdits(); // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); mgr.addEdit(new SampleUndoableEdit(2, false, true, false)); mgr.addEdit(new SampleUndoableEdit(3, false, true, false)); mgr.addEdit(new SampleUndoableEdit(4, false, true, false)); mgr.addEdit(new SampleUndoableEdit(5, false, true, false)); mgr.addEdit(new SampleUndoableEdit(6, false, true, false)); System.out.println("Changing limit example"); mgr.undo(); mgr.undo(); mgr.undo(); // Now 3 undoable, 3 redoable mgr.setLimit(4); // Now 2 undoable, 2 redoable! while (mgr.canUndo()) mgr.undo(); while (mgr.canRedo()) mgr.redo(); // undoOrRedo example mgr.discardAllEdits(); mgr.setLimit(1); // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); System.out.println("undoOrRedo example"); System.out.println(mgr.getUndoOrRedoPresentationName()); mgr.undoOrRedo(); System.out.println(mgr.getUndoOrRedoPresentationName()); mgr.undoOrRedo(); // Show how UndoManager becomes a CompositeEdit. mgr.discardAllEdits(); mgr.setLimit(100); // # adds? sig? replace? mgr.addEdit(new SampleUndoableEdit(1, false, true, false)); mgr.addEdit(new SampleUndoableEdit(2, false, true, false)); mgr.addEdit(new SampleUndoableEdit(3, false, true, false)); System.out.println("Transform to composite example"); mgr.end(); mgr.undo(); mgr.redo(); // Show that adds are no longer allowed. Note that addEdit() returns true in // pre-JDK 1.2 Swing releases. This is fixed in JDK 1.2. System.out.println(mgr.addEdit(new SampleUndoableEdit(4, false, true, false))); mgr.undo(); // note that edit 4 is not there }
} class SampleUndoableEdit extends AbstractUndoableEdit {
private boolean isSignificant; private boolean isReplacer; private int number; private boolean allowAdds; private Vector addedEdits; private UndoableEdit replaced; // Create a new edit with an identifying number. The boolean arguments define // the edit"s behavior. public SampleUndoableEdit(int number, boolean allowAdds, boolean isSignificant, boolean isReplacer) { this.number = number; this.allowAdds = allowAdds; if (allowAdds) addedEdits = new Vector(); this.isSignificant = isSignificant; this.isReplacer = isReplacer; } // "Undo" the edit by printing a message to the screen. public void undo() throws CannotUndoException { super.undo(); System.out.print("Undo " + number); dumpState(); } // "Redo" the edit by printing a message to the screen. public void redo() throws CannotRedoException { super.redo(); System.out.print("Redo " + number); dumpState(); } // If allowAdds is true, we store the input edit. If not, just return false. public boolean addEdit(UndoableEdit anEdit) { if (allowAdds) { addedEdits.addElement(anEdit); return true; } else return false; } // If isReplacer is true, we store the edit we are replacing. public boolean replaceEdit(UndoableEdit anEdit) { if (isReplacer) { replaced = anEdit; return true; } else return false; } // Significance is based on constructor parameter. public boolean isSignificant() { return isSignificant; } // Just return our identifier. public String toString() { return "<" + number + ">"; } // Debug output. public void dumpState() { if (allowAdds && addedEdits.size() > 0) { Enumeration e = addedEdits.elements(); System.out.print(" (absorbed: "); while (e.hasMoreElements()) { System.out.print(e.nextElement()); } System.out.print(")"); } if (isReplacer && replaced != null) { System.out.print(" (replaced: " + replaced + ")"); } System.out.println(); }
}
</source>