public void actionPerformed(ActionEvent e) {
            Object src = e.getSource();
            Calendar c = new GregorianCalendar();
            c.setTime(parent.getCalendar().getTime());
            if (src instanceof JButton) {
                if (e.getSource() == premon) {
                    c.add(Calendar.MONTH, -1);
                } else if (e.getSource() == nextmon) {
                    c.add(Calendar.MONTH, 1);
                } else if (e.getSource() == nextyear) {
                    c.add(Calendar.YEAR, 1);
                }
                if (e.getSource() == preyear) {
                    c.add(Calendar.YEAR, -1);
                }
                // System.out.println(c.getTime());
                parent.updateScreen(c);
            } else if (src instanceof JComboBox) {
                JComboBox jcb = (JComboBox) src;
                if (src == monthBox) {
                    c.set(Calendar.MONTH, jcb.getSelectedIndex());
                } else if (e.getSource() == yearBox) {
                    c.set(Calendar.YEAR, years[jcb.getSelectedIndex()].intValue());
                    setYearComboBox(c);
                }
                parent.setMonthPanel(c);
                parent.screen.pack();
            }
        }