rules.append(css.getText());
for (final Level level : Level.values()) {
String itemClass = LEVEL_CLASSES.get(level);
String containerClass = LEVEL_FILTER_PREFIX + itemClass;
FilterButton levelFilter = new FilterButton(new DoubleClickHandler() {
@Override
public void onDoubleClick(DoubleClickEvent event) {
enableOnlyMoreImportantLevels(level);
}
}, entries, containerClass, itemClass, level.name(), css.level());