items = new HashMap<String, JMenuItem>();
fileChooserAction = new FileChooserAction(observable, "Open", PdfFilter.INSTANCE, false);
MessageAction message = new MessageAction();
JMenu file = new JMenu(FILE_MENU);
addItem(file, OPEN, fileChooserAction);
addItem(file, CLOSE, new FileCloseAction(observable));
add(file);
add(Box.createGlue());
JMenu help = new JMenu(HELP_MENU);
addItem(help, ABOUT, message);
addItem(help, VERSIONS, message);