else if (MainFrame.getInstance().getViewType()==MainFrame.VIEW_WEEK) periodChooser.setDate(new Date(periodChooser.getDate().getTime()-anHalfYear));
else if (MainFrame.getInstance().getViewType()==MainFrame.VIEW_HALF_YEAR) periodChooser.setDate(new Date(periodChooser.getDate().getTime()-anHalfYear));
			public void actionPerformed(ActionEvent ae) {				if (MainFrame.getInstance().getViewType()==MainFrame.VIEW_WEEK)					periodChooser.setDate(new Date(periodChooser.getDate().getTime()-aWeek));				else if (MainFrame.getInstance().getViewType()==MainFrame.VIEW_WEEK)					periodChooser.setDate(new Date(periodChooser.getDate().getTime()-anHalfYear));					try {								model.fireShowTimetable(model.getTimetable()); //TODO modifier				} catch (InterruptedException e) {					System.err.println("calendar -- fire exception : "+e.getMessage());					e.printStackTrace();				}						}