@Override
    protected void setup() {
        // previous, next buttons
        monthBackwards = createNavigationButton(SvgImage.ARROW_LEFT, -1, css().previousButton());
        monthForwards = createNavigationButton(SvgImage.ARROW_RIGHT, 1, css().nextButton());
        yearBackwards = createNavigationButton(SvgImage.ARROW_LEFT, -12, css().previousYearButton());
        yearForwards = createNavigationButton(SvgImage.ARROW_RIGHT, 12, css().nextYearButton());

        // month and year selector
        monthSelect = createMonthSelect();
        yearSelect = createYearSelect();

        // Set up grid.
        layout = new FlowPanel();
        layout.setStyleName(css().monthSelector());

        setupGrid();

        initWidget(layout);
    }
Returns the ListBox for selecting the year
stroom-core-client-widget/src/main/java/stroom/widget/datepicker/client/DefaultMonthSelector.java