Understanding Action Objects in Java

/*ActionObj02.java 
Rev 03/30/02
Copyright 2002, R.G.Baldwin

Illustrates use of action objects.
Uses the setAction method that was 
released with V1.3

Tested using JDK 1.4.0 under 
Win2000.
**************************************/
import javax.swing.*;
import javax.swing.border.*;
import java.awt.*;
import java.awt.event.*;

public class ActionObj02{
  public static void main(
                        String[] args){
    new GUI();
  }//end main
}//end ActionObj02
//===================================//

class GUI extends JFrame{
  //Create three containers
  JMenuBar menuBar = new JMenuBar();
  JMenu menu = new JMenu("Menu");
  JToolBar toolBar = new JToolBar();
  JPanel panel = new JPanel();

  //Create two Action objects
  Action actionObj01 = new MyAction();
  Action actionObj02 = new MyAction();
  
  //Create four check boxes and a
  // control panel, which will be used
  // to manipulate the Action objects
  // and their visual components.
  JCheckBox ckBox01 = new JCheckBox(
                          "Disable01");
  JCheckBox ckBox02 = new JCheckBox(
                          "Disable02");
  JCheckBox ckBox03 = new JCheckBox(
                      "Toggle Icon01");
  JCheckBox ckBox04 = new JCheckBox(
                      "Toggle Icon02");
  JPanel controlPanel = new JPanel();
  
  GUI(){//constructor
    //Construct and decorate the menu
    // and put it in place.
    menuBar.add(menu);
    menuBar.setBorder(
               new BevelBorder(
                  BevelBorder.RAISED));
    setJMenuBar(menuBar);
    
    //Decorate the JToolBar and place
    // it in the North position.
    toolBar.setBorder(new BevelBorder(
                  BevelBorder.RAISED));
    getContentPane().add(
           toolBar,BorderLayout.NORTH);
    
    //Decorate the JPanel and place it
    // in the South position.
    panel.setBorder(new BevelBorder(
                  BevelBorder.RAISED));
    getContentPane().add(
             panel,BorderLayout.SOUTH);

    //Set some keyed properties for
    // each of the two Action objects.
    actionObj01.putValue(
            Action.NAME,"actionObj01");
    actionObj01.putValue(
       Action.SMALL_ICON,new ImageIcon(
                       "redball.gif"));
    actionObj01.putValue(
            Action.SHORT_DESCRIPTION,
            "ToolTip for actionObj01");
 
    actionObj02.putValue(
            Action.NAME,"actionObj02");
    actionObj02.putValue(
       Action.SMALL_ICON,new ImageIcon(
                         "bulb2.gif"));
    actionObj02.putValue(
            Action.SHORT_DESCRIPTION,
            "ToolTip for actionObj02");

    //Put a JMenuItem on the menu.  Set
    // its Action object using the
    // setAction method. This is 
    // one approach.
    JMenuItem mnuA1 = new JMenuItem();
    mnuA1.setAction(actionObj01);
    menu.add(mnuA1);

    //Put a JMenuItem on the menu. Set
    // its Action object in the
    // constructor. This is a 
    // different approach.
    JMenuItem mnuA2 = 
            new JMenuItem(actionObj02);
    menu.add(mnuA2);


    //Put a JButton on the toolbar.
    // Set its Action object using the
    // setAction method.  Also register
    // an ordinary Action listener
    // on it.
    JButton butB1 = new JButton();
    butB1.addActionListener(
      new ActionListener(){
        public void actionPerformed(
                        ActionEvent e){
          System.out.println(
           "Ordinary Action Listener");
        }//end actionPerformed()
      }//end ActionListener
    );//end addActionListener
    butB1.setAction(actionObj01);
    toolBar.add(butB1);

    //Put a JButton on the toolbar.
    // Set its Action object.
    JButton butB2 = new JButton();
    butB2.setAction(actionObj02);
    toolBar.add(butB2);

    //Put a JButton on the JPanel.
    // Set its Action object.
    JButton butC = new JButton();
    butC.setAction(actionObj01);
    panel.add(butC);

    //Put a JMenuItem on the JPanel.
    // Set its Action object.
    JMenuItem mnuC = new JMenuItem();
    mnuC.setAction(actionObj02);
    panel.add(mnuC);


    //Construct the control panel and
    // put it in the Center
    controlPanel.setLayout(
              new GridLayout(2,2,3,3));
    controlPanel.add(ckBox01);
    controlPanel.add(ckBox02);
    controlPanel.add(ckBox03);
    controlPanel.add(ckBox04);
    getContentPane().add(controlPanel,
                  BorderLayout.CENTER);
    
    //Set the size and make the GUI
    // visible
    setSize(350,200);
    setVisible(true);
    setTitle("Copyright 2002, " +
                        "R.G.Baldwin");
   
    //The following anonymous inner
    // allow the user to manipulate the
    // Action objects and their 
    // associated visual components.
    
    //Register ActionListener objects
    // on each of the check boxes.
    // This makes it possible to 
    // disable and enable the two
    // Actions objects independently of
    // one another.  It also makes it
    // possible to toggle the icons
    // between two different images
    // on each Action object when the
    // Action object is enabled.
    ckBox01.addActionListener(
      new ActionListener(){
        public void actionPerformed(
                        ActionEvent e){
          if(e.getActionCommand().
                  equals("Disable01")){
            ckBox01.setText(
                           "Enable01");
            actionObj01.setEnabled(
                                false);
            //Disable ability to toggle
            // the IconImage.
            ckBox03.setEnabled(false);
          }else{
            ckBox01.setText(
                          "Disable01");
            actionObj01.setEnabled(
                                 true);
            //Enable ability to toggle
            // the IconImage.
            ckBox03.setEnabled(true);
          }//end else
        }//end actionPerformed()
      }//end ActionListener
    );//end addActionListener
  
    ckBox02.addActionListener(
      new ActionListener(){
        public void actionPerformed(
                        ActionEvent e){
          if(e.getActionCommand().
                  equals("Disable02")){
            ckBox02.setText(
                           "Enable02");
            actionObj02.setEnabled(
                                false);
            //Disable ability to toggle
            // the IconImage.
            ckBox04.setEnabled(false);
          }else{
            ckBox02.setText(
                          "Disable02");
            actionObj02.setEnabled(
                                 true);
            //Enable ability to toggle
            // the IconImage.
            ckBox04.setEnabled(true);
          }//end else
        }//end actionPerformed()
      }//end ActionListener
    );//end addActionListener

    ckBox03.addActionListener(
      new ActionListener(){
        public void actionPerformed(
                        ActionEvent e){
          //Get file name for the
          // ImageIcon object.
          String gif = (actionObj01.
                 getValue(
                   Action.SMALL_ICON)).
                            toString();

          if((gif).equals(
                       "redball.gif")){
            actionObj01.putValue(
                     Action.SMALL_ICON,
                      new ImageIcon(
                      "blueball.gif"));
          }else{
            actionObj01.putValue(
               Action.SMALL_ICON,
                         new ImageIcon(
                       "redball.gif"));
          }//end else
           
        }//end actionPerformed()
      }//end ActionListener
    );//end addActionListener    
   
    ckBox04.addActionListener(
      new ActionListener(){
        public void actionPerformed(
                        ActionEvent e){
          //Get file name for the
          // ImageIcon object.
          String gif = (actionObj02.
                 getValue(
                   Action.SMALL_ICON)).
                            toString();

          if((gif).equals(
                       "bulb2.gif")){
            actionObj02.putValue(
               Action.SMALL_ICON,
                         new ImageIcon(
                      "bulb1.gif"));
          }else{
            actionObj02.putValue(
               Action.SMALL_ICON,
                         new ImageIcon(
                         "bulb2.gif"));
          }//end else
           
        }//end actionPerformed()
      }//end ActionListener
    );//end addActionListener

    //Create a WindowListener used
    // to terminate the program
    this.addWindowListener(
      new WindowAdapter(){
        public void windowClosing(
                        WindowEvent e){
          System.exit(0);
        }//end windowClosing()
      }//end WindowAdapter
    );//end addWindowListener
  }//end constructor
}//end GUI class

//===================================//

//This is the class from which the
// Action objects are instantiated.
class MyAction extends AbstractAction{
  public void actionPerformed(
                        ActionEvent e){
    System.out.println("Action: " + 
       ((AbstractButton)e.getSource()).
                   getActionCommand());
  }//end actionPerformed
}//end class MyAction

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