Question

In my custom JFileChooser, I want to get the Open button, so I am using the following code:

private static JButton getOpenButton(Container c) {
  Validator.checkNull(c);

  int len = c.getComponentCount();
  JButton button = null;
  for (int index = 0; index < len; index++) {
    if (button != null) {
      break;
    }
    Component comp = c.getComponent(index);
    if (comp instanceof JButton) {
      JButton b = (JButton) comp;

      if ("Open".equals(b.getText())) {
        return b;
      }
    }
    else if (comp instanceof Container) {
      button = getOpenButton((Container) comp);
    }
  }
  return button;
}

The problem with this code is that it is inefficient (because of recursion) and also can be broken if localization is used (because the word “Open” is hard-coded).

I also want to get the JTextField in which the user can enter the name and path of a file. I am using this code to get this component:

private static JTextField getTextField(Container c) {
  Validator.checkNull(c);

  int len = c.getComponentCount();
  JTextField textField = null;
  for (int index = 0; index < len; index++) {
    if (textField != null) {
      break;
    }
    Component comp = c.getComponent(index);
    if (comp instanceof JTextField) {
      return (JTextField) comp;
    }
    else if (comp instanceof Container) {
      textField = getTextField((Container) comp);
    }
  }
  return textField;
}

Is there a better way I can get the Open button and the JTextField?

Answer 1

In the constructor of my custom file chooser, I called the setApproveButtonText method and passed in a custom string to use for the Open button. I called this method before I get the Open button using the getOpenButton method below. This way, I am guaranteed to get the Open button on any OS platform and no matter what locale the JVM is using.

private final String title;

public CustomFileChooser(String title) {
  this.title = title;
  setApproveButtonText(title);
  this.button = getOpenButton(this);
}

private JButton getOpenButton(Container c) {
  Validator.checkNull(c);

  int len = c.getComponentCount();
  JButton button = null;
  for (int index = 0; index < len; index++) {
    if (button != null) {
      break;
    }
    Component comp = c.getComponent(index);
    if (comp instanceof JButton) {
      JButton b = (JButton) comp;

      if (this.title.equals(b.getText())) {
        return b;
      }
    }
    else if (comp instanceof Container) {
      button = getOpenButton((Container) comp);
    }
  }
  return button;
}