JToggleButton button = new JToggleButton(blockLayoutAction);
button.setSelected(true);
toolBar.add(button);
blockLayoutAction.addPropertyChangeListener(this);
overviewAction = new OverviewAction();
overviewButton = new JToggleButton(overviewAction);
overviewButton.setSelected(false);
toolBar.add(overviewButton);
overviewAction.addPropertyChangeListener(this);