Question

I’m learning Swing and have composed an interface using a series of get methods to add components. Is it a good practise to add a Listener inside a get method as follows? I’d like to make things as decoupled as possible.

 private JButton getConnectButton() {
  if (connectButton == null) {
   connectButton = new JButton();
   connectButton.setText("Connect");
   connectButton.setSize(new Dimension(81, 16));
   connectButton.setLocation(new Point(410, 5));

   connectButton.addActionListener(new ActionListener() {
    public void actionPerformed(ActionEvent e) {
     // actionPerformed code goes here
    }
   });

  }
  return connectButton;
 }

Answer 1

From my extensive practice as a Swing developer I can tell you that it’s not good practice to obtain component instances in this manner(via getters). I generally setup the UI for a Frame/Dialog in some method like initComponents() and afterwards add all the listeners in some method like addListeners(). I’m not sure if that there is a single best practice as how to do things – there a lot of options and personal preferences. Generally, however, lazy init of components that you’ll need anyways(like this button I presume) is unneeded.

Also – you should really consider using some layout manager such a MiG and avoid hardcoded component sizes.