extends AbstractAction : Action « Swing Event « Java Tutorial

1. Java Tutorial
2. Swing Event
3. Action

import java.awt.BorderLayout;
import java.awt.event.ActionEvent;

import javax.swing.AbstractAction;
import javax.swing.Action;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JScrollPane;
import javax.swing.JTextPane;
import javax.swing.event.UndoableEditEvent;
import javax.swing.event.UndoableEditListener;
import javax.swing.undo.UndoManager;

public class UndoEditor extends JFrame {
  private UndoManager undoManager = new UndoManager();
  private JMenuBar menuBar = new JMenuBar();
  private JMenu editMenu = new JMenu("Edit");
  private UndoAction undoAction = new UndoAction();
  private RedoAction redoAction = new RedoAction();

  public UndoEditor() {
    setLayout(new BorderLayout());
    this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    JTextPane editor = new JTextPane();
    editor.getDocument().addUndoableEditListener(new UndoListener());

    menuBar.add(editMenu);
    editMenu.add(undoAction);
    editMenu.add(redoAction);
    this.setJMenuBar(menuBar);
    add(new JScrollPane(editor));
    setSize(400, 300);
    setVisible(true);
  }

  public static void main(String[] args) {
    UndoEditor e = new UndoEditor();
  }

  class UndoListener implements UndoableEditListener {
    public void undoableEditHappened(UndoableEditEvent e) {
      undoManager.addEdit(e.getEdit());
      undoAction.update();
      redoAction.update();
    }
  }

  class UndoAction extends AbstractAction {
    public UndoAction() {
      this.putValue(Action.NAME, undoManager.getUndoPresentationName());
      this.setEnabled(false);
    }

    public void actionPerformed(ActionEvent e) {
      if (this.isEnabled()) {
        undoManager.undo();
        undoAction.update();
        redoAction.update();
      }
    }

    public void update() {
      this.putValue(Action.NAME, undoManager.getUndoPresentationName());
      this.setEnabled(undoManager.canUndo());
    }
  }

  class RedoAction extends AbstractAction {
    public RedoAction() {
      this.putValue(Action.NAME, undoManager.getRedoPresentationName());
      this.setEnabled(false);
    }

    public void actionPerformed(ActionEvent e) {
      if (this.isEnabled()) {
        undoManager.redo();
        undoAction.update();
        redoAction.update();
      }
    }

    public void update() {
      this.putValue(Action.NAME, undoManager.getRedoPresentationName());
      this.setEnabled(undoManager.canRedo());
    }
  }
}

15.3.Action
	15.3.1.	AbstractAction Lookup Property Keys
	15.3.2.	Creating an Action
	15.3.3.	Action Usage Example
	15.3.4.	extends AbstractAction
	15.3.5.	Disable an Action
	15.3.6.	Get and set Action Command
	15.3.7.	Register action
	15.3.8.	ActionMap javax.swing.JComponent.getActionMap()
	15.3.9.	Map actions with keystrokes
	15.3.10.	Enabling an Action
	15.3.11.	Listing the Actions in a Component