Question

Im new to java and im trying to build a simple GUI with several buttons and drop down menus. Ive managed to get a working GUI but the real question is about the proper use of the actionListener method. In order to assign an action to a button i inserted each actionListener in its own class, this is the code:

public class GUI implements something
{
    public static ClientGUI App;
    private JFrame chatWin;
    private JMenuBar menubar;
    private JMenu x;
    private JMenu y;
    private JMenuItem exit;
    private JMenuItem about;


    public GUI()
    {

               /* 
                * some code and parameters
                */

            //creating the menu bar
            JMenuBar menubar = new JMenuBar();
            chatWin.setJMenuBar(menubar);

            JMenu x= new JMenu("menu1");
            menubar.add(x);
            JMenuItem exit = new JMenuItem("menu2");
            x.add(exit);

            JMenu y= new JMenu("Help");
            menubar.add(help);
            JMenuItem about = new JMenuItem("inner menu1");
            y.add(about);

            //action listener for the exit button 
            class exitaction implements ActionListener
            {
                public void actionPerformed(ActionEvent e)
                {
                    System.exit(0);
                }
            }
            exit.addActionListener(new exitaction());

            //action listener for the about button
            class aboutaction implements ActionListener
            {
                public void actionPerformed(ActionEvent e)
                {
                    //some code
                }

            }
        }

    public static void main (String args[])
    {
        EventQueue.invokeLater(new Runnable()
        {
            public void run()
            {
                App = new GUI();
            }
        });
    }


}

Is that code is considered to be neat and correct? is there anything i could improve or need to change?

Answer 1

I follow the rule:

If the action implementation is great, I put in a inner class.

    public MyFrame extends JFrame {

       // componentes creating, etc

        private static class MyShortAction implements ActionListener {

            @Override
            public void actionPerformed(ActionEvent e){
                // some big implementation
            }

        }

    }

When short, i put in a anonymous class.

myButton.addActionListener(new ActionListener() {

    @Override
    public void actionPerformed(ActionEvent e){
        // some small code
    }

});

If it is used by other components, I extract to a top level class.

public class MyAction implements ActionListener {

    @Override
    public void actionPerformed(ActionEvent e){
        // some small code
    }
}