public void setMaxDayCharacters(int maxDayCharacters) {
        if (maxDayCharacters == this.maxDayCharacters) {
            return;
        }

        if (maxDayCharacters < 0 || maxDayCharacters > 4) {
            this.maxDayCharacters = 0;
        } else {
            this.maxDayCharacters = maxDayCharacters;
        }
        drawDayNames();
        drawDays();
        invalidate();
    }