使相同的常规JButton根据其子类做不同的事情

Question

I have a very simple Bank Account going on, that I built to practice my MVC knowledge. However I've hit a snag.

Since the Deposit and Withdraw screens are essentially the same, I abstracted almost all of it to a BaseWindow class.

This is the BaseWindow class:

public class BaseWindow extends JFrame {

    private static final long serialVersionUID = 4741220023341218042L;

    JButton executeButton;

    public BaseWindow(String title){
        super(title);
        JPanel panel = new JPanel(new GridLayout(0, 3));
        JLabel amountLabel = new JLabel("Amount: "); 
        JTextField inputBox = new JTextField(15);
        executeButton = new JButton("Execute");
        JLabel newBalanceLabel = new JLabel("New Balance: "); 
        JLabel newBalance = new JLabel();
        panel.add(amountLabel);
        panel.add(inputBox);
        panel.add(executeButton);
        panel.add(newBalanceLabel);
        panel.add(newBalance);
        panel.add(new JLabel()); //Empty, for layout purposes
        add(panel);
        pack();
    }

    public JButton getExecuteButton(){
        return executeButton;
    }
}

The Problem

Since I'm using the Model-View-Controller pattern, the function of the Execute button is determined in the Controller class, which is consists of the following:

...
public void startDepositWindow(){
        DepositWindow depositWindow = view.createDepositWindow();
        depositWindow.getExecuteButton().addActionListener(createExecuteButtonListener());
        depositWindow.run();
    }
    public void startWithdrawWindow(){
        WithdrawWindow withdrawWindow = view.createWithdrawWindow();
        withdrawWindow.getExecuteButton().addActionListener(createExecuteButtonListener());
        withdrawWindow.run();
    }

    //Button Action Listeners
    private ActionListener createDepositButtonListener(){
        return new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                startDepositWindow();
            }
        };
    }
    private ActionListener createWithdrawButtonListener(){
        return new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                startWithdrawWindow();
            }
        };
    }
    private ActionListener createExecuteButtonListener(){
        return new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                // WHAT GOES HERE??
            }
        };
    }

...

The problem is, I can't think of what goes in the createExecuteButtonListener because I can't simply say model.deposit() or model.withdraw() because I don't know which window the Execute button was clicked inside of.

As far as I know, I can't use Polymorphism here because the listener is not being bound inside the DepositWindow or WithdrawWindow subclasses and I don't want to call them there since that would violate Model-View-Controller.

So what's bothering me is, how do I tell the button listener/controller what is the right thing to do?

Answer 1

Use Action "to separate functionality and state from a component." Let the model export a suitable DepositAction and WithdrawAction . Let the controller associate each action with the correct Execute button. Some related examples are cited here .