TextField f1 = createTextField("Text field 1", "");
final TextField f2 = createTextField("Text field 2", "bold");
fl.addComponent(f1);
fl.addComponent(new Button("Toggle Text field 2 bold style",
new Button.ClickListener() {
@Override
public void buttonClick(ClickEvent event) {
if ("bold".equals(f2.getStyleName())) {