.setNumberOfDisplayedTabs(model.numberOfPanes());
controller = new HorizontalTabController();
} else if (header instanceof HorizontalTabTitleView) {
header = new HorizontalScrollableTitleView(Field.FOCUSABLE);
((HorizontalScrollableTitleView) header).enableArrows(true);
controller = new HorizontalScrollableController();
if (_leftArrow != null) {
header.setLeftArrow(_leftArrow);
}
if (_rightArrow != null) {