jcalendarpanel.java

日历控件

		buttonpanel.add(yearRight, c);

		return buttonpanel;
	}

	/**
	 * Creates a JComboBox filled with year values (1900-2100)
	 * @return JComboBox with Years
	 */
	private JComboBox createYear() {
		JComboBox year = new JComboBox();

		for (int i = 1900; i <= 2100; i++) {
			year.addItem("" + i); //$NON-NLS-1$
		}

		year.setSelectedIndex(_cal.get(Calendar.YEAR) - 1900);

		return year;
	}

	/**
	 * Creates a JComboBox filled with Months.
	 * The name for the Month is created using the locale given
	 * in the constructor.
	 * 
	 * @return JComboBox filled with Months
	 */
	private JComboBox createMonth() {
		JComboBox month = new JComboBox();

		SimpleDateFormat format = new SimpleDateFormat("MMMMM", _locale);

//		 Probably should be using the same locale as the rest of the widget.
		Calendar currentCal = Calendar.getInstance(_locale);
//		 Setting the day to 1 will avoids problems with leap years.
//		 If the calendar is created on March 30, 2004 (like I just did)
//		 then the day defaults to 30.  When the month is set to 1 (February)  
//		 the currentCal will *adjust* it to become March 1.  This results
//		 in TWO entries with the value of \"March\" in the month combo.
		currentCal.set(Calendar.DAY_OF_MONTH, 1);
		
		for (int i = 0; i < 12; i++) {
			currentCal.set(Calendar.MONTH, i);
			currentCal.set(Calendar.YEAR, _cal.get(Calendar.YEAR));
			String myString = format.format(currentCal.getTime());
			month.addItem(myString);
		}

		month.setSelectedIndex(_cal.get(Calendar.MONTH));

		return month;
	}

	/**
	 * Updates the Calendar
	 */
	private void updateCalendar() {
		if (!_updating) {
			_updating = true;
			_cal.set(Calendar.MONTH, _month.getSelectedIndex());
			_cal.set(Calendar.YEAR, _year.getSelectedIndex() + 1900);
			_cal.set(Calendar.DAY_OF_MONTH, _monthPanel.getSelectedDayOfMonth());

			_monthPanel.setCalendar(_cal);
			_monthPanel.grabFocus();
			_updating = false;
		}
	}

	/**
	 * Returns the current selected Date as Calender-Object
	 * 
	 * @return current selected Date
	 */
	public Calendar getCalendar() {
		updateCalendar();
		return _cal;
	}

	/**
	 * Sets the current selected Date
	 * 
	 * @param cal the Date to select
	 */
	public void setCalendar(Calendar cal) {
		_updating = true;
		_cal.set(Calendar.DAY_OF_MONTH, cal.get(Calendar.DAY_OF_MONTH));
		_cal.set(Calendar.MONTH, cal.get(Calendar.MONTH));
		_cal.set(Calendar.YEAR, cal.get(Calendar.YEAR));

		_monthPanel.setCalendar(_cal);
		_year.setSelectedIndex(_cal.get(Calendar.YEAR) - 1900);
		_month.setSelectedIndex(_cal.get(Calendar.MONTH));
		_monthPanel.grabFocus();
		_updating = false;
	}

	/**
	 * Returns a String-Representation of this Calendar using
	 * the DateFormat given in the Constructor
	 * 
	 * @return String-Representation of this Calendar
	 */
	public String toString() {
		updateCalendar();
		return _format.format(_cal.getTime());
	}

	/**
	 * Returns a String-Representation of this Calendar
	 * using the given DateFormat
	 * 
	 * @param format DateFormat to use
	 * @return String-Representation of this Calendar
	 */
	public String toString(DateFormat format) {
		updateCalendar();
		return format.format(_cal.getTime());
	}

	/** 
	 * Recieves StateChanges from the ComboBoxes for Month/Year
	 * and updates the Calendar
	 * 
	 * @param e ItemEvent
	 * @see java.awt.event.ItemListener#itemStateChanged(java.awt.event.ItemEvent)
	 */
	public void itemStateChanged(ItemEvent e) {
		updateCalendar();
		if (_listenermode == FIRE_EVERYTIME) {
			fireChangeEvent();
		}
	}

	/**
	 * Recieves StateChanges from the MonthPanel and
	 * updates the Calendar
	 * 
	 * @param e ChangeEvent
	 * 
	 * @see javax.swing.event.ChangeListener#stateChanged(javax.swing.event.ChangeEvent)
	 */
	public void stateChanged(ChangeEvent e) {
		updateCalendar();
		fireChangeEvent();
	}

	/**
	 * Adds a Changelistener to this JCalendarPanel.
	 * 
	 * It will be called every time the selected Date
	 * changes.
	 * 
	 * @param listener ChangeListener
	 */
	public void addChangeListener(ChangeListener listener) {
		_changeListener.add(listener);
	}

	/**
	 * Removes a ChangeListener from this JCalendarPanel
	 * 
	 * @param listener listener to remove
	 */
	public void removeChangeListener(ChangeListener listener) {
		_changeListener.remove(listener);
	}

	/**
	 * Gets all ChangeListeners
	 * @return all ChangeListeners
	 */
	public ChangeListener[] getChangeListener() {
		return (ChangeListener[]) _changeListener.toArray();
	}

	/**
	 * Fires the ChangeEvent
	 */
	protected void fireChangeEvent() {
		if (!_fireingChangeEvent) {
			_fireingChangeEvent = true;
			ChangeEvent event = new ChangeEvent(this);

			for (int i = 0; i < _changeListener.size(); i++) {
				((ChangeListener) _changeListener.get(i)).stateChanged(event);
			}

			_fireingChangeEvent = false;
		}

	}

	/**
	 * Sets the Mode when the FireChangeEvent is called.
	 * Use FIRE_EVERYTIME or FIRE_DAYCHANGES as parameter.
	 * 
	 * @param mode The Mode of the Listener
	 */
	public void setListenerModus(int mode) {
		_listenermode = mode;
	}

	/**
	 * Enables/Disables the Panel
	 * @param enabled Enabled ?
	 */
	public void setEnabled(boolean enabled) {
		_month.setEnabled(enabled);
		_year.setEnabled(enabled);
		_monthPanel.setEnabled(enabled);
	}

	/**
	 * Is the Panel enabled ?
	 * @return enabled ?
	 */
	public boolean isEnabled() {
		return _month.isEnabled();
	}

	/**
	 * Returns the Dateformat the Panel is using
	 * @return DateFormat
	 */
	public DateFormat getDateFormat() {
	    return _format;
	}
	
	/**
	 * Fires everytime the Date changes
	 */
	public static final int FIRE_EVERYTIME = 1;
	/**
	 * Fires only if the Day changes
	 */
	public static final int FIRE_DAYCHANGES = 2;

	/**
	 * When does FireEvent() fire events?
	 * Every time there is an update or only
	 * if the Day was changed?
	 */
	private int _listenermode = FIRE_EVERYTIME;

	/**
	 * Current chang in progress?
	 */
	private boolean _updating = false;

	/**
	 * The current Date
	 */
	private Calendar _cal;
	/**
	 * The DateFormat for Output
	 */
	private DateFormat _format;
	/**
	 * The Locale to use
	 */
	private Locale _locale;

	/**
	 * The JComboBox for Month-Selection
	 */
	private JComboBox _month;
	/**
	 * The JComboBox for Year-Selection
	 */
	private JComboBox _year;
	/**
	 * The JMonthPanel for Day-Selection
	 */
	private JMonthPanel _monthPanel;

	/**
	 * The list of ChangeListeners
	 */
	private ArrayList _changeListener = new ArrayList();
	/**
	 * Currently firing an ChangeEvent?
	 */
	private boolean _fireingChangeEvent = false;
}