注册屏幕日期字段验证！

  final Date currentDate = new Date();
  dateField.setDate(currentDate);
  dateField = new DateField (\"Birthday:\", 567993600, DateField.DATE | DateField.FIELD_LEFT){

        public void paint(Graphics g){

            g.setColor(Color.WHITE); 
            super.paint(g); } 
                    };;; 

SubmitButton

setChangeListener

SubmitButton.setChangeListener( new FieldChangeListener() {
                    public void fieldChanged( Field arg0, int arg1 ) { 

    //I think the fallowing step saves data as a String in bDayString 

      String bDayString = dateField.toString();

String[] formatdate = UILib.splitString(bDayString, \"\");

if (!UILib.isDateValid(bDayString))

{
     Alert(\"Register Error\", \"Invalid date\", false);
            return;
                        }