private void bumpStaff() {
        Platform.runLater(new Runnable() {

            @Override
            public void run() {
                scrollbar.adjustValue(scrollbar.getValue() + skipAmount);
                if (scrollbar.getMax() <= scrollbar.getValue() && endOfFile) {
                    scrollbar.setMax(scrollbar.getMax()
                            + Values.NOTELINES_IN_THE_WINDOW * 2);
                    StaffSequence s = theStaff.getSequence();
                    int start = (int) scrollbar.getMax();
                    for (int i = start; i < start
                            + Values.NOTELINES_IN_THE_WINDOW * 2; i++)
                        s.addLine(new StaffNoteLine());
                }
                if (scrollbar.getMax() <= scrollbar.getValue())
                    endOfFile = true;
                else
                    endOfFile = false;
            }
        });
    }