Question

I have a big table containing a button in each cell. These buttons are very similar and do almost the same. If I add an action listener to every button in this way:

tmp.addActionListener(new ActionListener(){
   @Override
   public void actionPerformed(ActionEvent evt) {
      proposition = proposition + action;
      SwingUtilities.invokeLater(new Runnable() {
         public void run() {
            updatePropositionPanel();
         }
      });
   }
});

Actually, every action listener differ from all others by the value of the action. proposition and updatePropositionPanel are a field and a method of the class.

1. First i thought that I can make it shorter if I do not use inner classes. So, I decided to program a new ActionListener class. But than I realized that in this case “proposition” will not be visible to the instances of this class.

2. Then I decided to add the actionPerformed method to the current class and do that: addActionListener(this). But than I realized that I do not know how give arguments to the actionPerformed method.

So, how does it work. Can I add an action listener in a short and elegent way?

ADDED:

I liked the idea to program an inner class with a constructor which can take some arguments and actioPerformed method, which can use arguments given in the constructor. I started to do so and then realized that it creates a conflicts with other inner anonymous classes (used like in the above given code). So, I think I will create another class (not inner one).

Answer 1

You can create your own class and pass the data into the constructor. For example

public class MyActionListener
{
    private int proposition;
    private MyOtherClass moc;

    public MyActionListener(int proposition, MyOtherClass moc) {
        this.proposition = proposition;
        this.moc = moc;
    }

    public void actionPerformed(ActionEvent evt) {
        proposition += moc.action;
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                moc.updatePropositionPanel();
            }
        });
    }
}

Then you can add it as normal, passing whatever arguments you like to the constructor:

tmp.addActionListener( new MyActionListener(proposition, this) );