@Override
            public void actionPerformed(ActionEvent e) {
                updateDisplayChoices();
            }
<code>setUpChooser</code> retrieves all available display modes and
places them in a <code>JComboBox</code>. The resolution specified by
AppSettings is used as the default value.

@return the combo box of display modes.
jme3-awt-dialogs/src/main/java/com/jme3/awt/AWTSettingsDialog.java