Class UndoListener

  extended by ptolemy.gui.UndoListener
All Implemented Interfaces:
java.util.EventListener, javax.swing.event.UndoableEditListener

public class UndoListener
extends java.lang.Object
implements javax.swing.event.UndoableEditListener

An Undo/Redo listener for use with a JTextComponent.

A convenience constructor has been provided such that a caller can immediately have default shortcut key mappings for undo/redo actions on the text component

Ptolemy II 8.0
$Id: 57044 2010-01-27 22:41:05Z cxh $
Ben Leinfelder, ben leinfelder
Accepted Rating:
Red (cx)
Proposed Rating:
Yellow (cxh)

Nested Class Summary
protected  class UndoListener.RedoAction
          Peform the redo action.
protected  class UndoListener.UndoAction
          Perform the undo action.
Field Summary
protected  UndoListener.RedoAction _redoAction
          The redo action.
protected  javax.swing.undo.UndoManager _undo
          The undo manager.
protected  UndoListener.UndoAction _undoAction
          The undo action.
Constructor Summary
          Construct an undo listener.
UndoListener(javax.swing.text.JTextComponent textArea)
          Construct an undo listener with default key mappings.
Method Summary
 void undoableEditHappened(javax.swing.event.UndoableEditEvent event)
          Remember the edit and update the action state.
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail


protected UndoListener.UndoAction _undoAction
The undo action.


protected UndoListener.RedoAction _redoAction
The redo action.


protected javax.swing.undo.UndoManager _undo
The undo manager.

Constructor Detail


public UndoListener()
Construct an undo listener.

This constructor allows simple usage without setting up key mapping automatically (it is then the responsibilty of the caller to provide a mechanism for invoking the undo and redo actions.)


public UndoListener(javax.swing.text.JTextComponent textArea)
Construct an undo listener with default key mappings. The default key mappings invoke the undo and redo actions on textArea .

A typical usage pattern would be: JTextArea textArea = new JTextArea("testing"); textArea.getDocument().addUndoableEditListener(new UndoListener(textArea));

textArea - the text component that is being listened to and upon which undo/redo actions will be performed
Method Detail


public void undoableEditHappened(javax.swing.event.UndoableEditEvent event)
Remember the edit and update the action state.

Specified by:
undoableEditHappened in interface javax.swing.event.UndoableEditListener
event - The event that occurred.