Content of DateChooser.java extracted from search.jar
package search; import java.awt.*; import java.awt.event.*; import java.util.*; import javax.swing.*; import javax.swing.border.*; import javax.swing.table.*; /** * Custom dialog box to enter dates. The <code>DateChooser</code> * class presents a calendar and allows the user to visually select a * day, month and year so that it is impossible to enter an invalid * date. **/ public class DateChooser extends JDialog implements ItemListener, MouseListener, FocusListener, KeyListener, ActionListener { /** Names of the months. */ private static final String[] MONTHS = new String[] { "January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December" }; /** Names of the days of the week. */ private static final String[] DAYS = new String[] { "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat" }; /** Text color of the days of the weeks, used as column headers in the calendar. */ private static final Color WEEK_DAYS_FOREGROUND = Color.black; /** Text color of the days' numbers in the calendar. */ private static final Color DAYS_FOREGROUND = Color.blue; /** Background color of the selected day in the calendar. */ private static final Color SELECTED_DAY_FOREGROUND = Color.white; /** Text color of the selected day in the calendar. */ private static final Color SELECTED_DAY_BACKGROUND = new Color(0,50,150); /** Empty border, used when the calendar does not have the focus. */ private static final Border EMPTY_BORDER = BorderFactory.createEmptyBorder(1,1,1,1); /** Border used to highlight the selected day when the calendar has the focus. */ private static final Border FOCUSED_BORDER = BorderFactory.createLineBorder(new Color(60,0,150),1); /** First year that can be selected. */ private static final int FIRST_YEAR = 1970; /** Last year that can be selected. */ private static final int LAST_YEAR = 2030; /** Auxiliary variable to compute dates. */ private GregorianCalendar calendar; /** Calendar, as a matrix of labels. The first row represents the first week of the month, the second row, the second week, and so on. Each column represents a day of the week, the first is Sunday, and the last is Saturday. The label's text is the number of the corresponding day. */ private JLabel[][] days; /** Day selection control. It is just a panel that can receive the focus. The actual user interaction is driven by the <code>DateChooser</code> class. */ private FocusablePanel daysGrid; /** Month selection control. */ private JComboBox month; /** Year selection control. */ private JComboBox year; /** "Ok" button. */ private JButton ok; /** "Cancel" button. */ private JButton cancel; /** Day of the week (0=Sunday) corresponding to the first day of the selected month. Used to calculate the position, in the calendar ({@link #days}), corresponding to a given day. */ private int offset; /** Last day of the selected month. */ private int lastDay; /** Selected day. */ private JLabel day; /** <code>true</code> if the "Ok" button was clicked to close the dialog box, <code>false</code> otherwise. */ private boolean okClicked; /** * Custom panel that can receive the focus. Used to implement the * calendar control. **/ private static class FocusablePanel extends JPanel { /** * Constructs a new <code>FocusablePanel</code> with the given * layout manager. * * @param layout layout manager **/ public FocusablePanel( LayoutManager layout ) { super( layout ); } /** * Always returns <code>true</code>, since * <code>FocusablePanel</code> can receive the focus. * * @return <code>true</code> **/ public boolean isFocusable() { return true; } } /** * Initializes this <code>DateChooser</code> object. Creates the * controls, registers listeners and initializes the dialog box. **/ private void construct() { calendar = new GregorianCalendar(); month = new JComboBox(MONTHS); month.addItemListener( this ); year = new JComboBox(); for ( int i=FIRST_YEAR; i<=LAST_YEAR; i++ ) year.addItem( Integer.toString(i) ); year.addItemListener( this ); days = new JLabel[7][7]; for ( int i=0; i<7; i++ ) { days[0][i] = new JLabel(DAYS[i],JLabel.RIGHT); days[0][i].setForeground( WEEK_DAYS_FOREGROUND ); } for ( int i=1; i<7; i++ ) for ( int j=0; j<7; j++ ) { days[i][j] = new JLabel(" ",JLabel.RIGHT); days[i][j].setForeground( DAYS_FOREGROUND ); days[i][j].setBackground( SELECTED_DAY_BACKGROUND ); days[i][j].setBorder( EMPTY_BORDER ); days[i][j].addMouseListener( this ); } ok = new JButton("Ok"); ok.addActionListener( this ); cancel = new JButton("Cancel"); cancel.addActionListener( this ); JPanel monthYear = new JPanel(); monthYear.add( month ); monthYear.add( year ); daysGrid = new FocusablePanel(new GridLayout(7,7,5,0)); daysGrid.addFocusListener( this ); daysGrid.addKeyListener( this ); for ( int i=0; i<7; i++ ) for ( int j=0; j<7; j++ ) daysGrid.add( days[i][j] ); daysGrid.setBackground( Color.white ); daysGrid.setBorder( BorderFactory.createLoweredBevelBorder() ); JPanel daysPanel = new JPanel(); daysPanel.add( daysGrid ); JPanel buttons = new JPanel(); buttons.add( ok ); buttons.add( cancel ); Container dialog = getContentPane(); dialog.add( "North", monthYear ); dialog.add( "Center", daysPanel ); dialog.add( "South", buttons ); pack(); setResizable( false ); } /** * Gets the selected day, as an <code>int</code>. Parses the text * of the selected label in the calendar to get the day. * * @return the selected day or -1 if there is no day selected **/ private int getSelectedDay() { if ( day == null ) return -1 ; try { return Integer.parseInt(day.getText()); } catch ( NumberFormatException e ) { } return -1; } /** * Sets the selected day. The day is specified as the label * control, in the calendar, corresponding to the day to select. * * @param newDay day to select **/ private void setSelected( JLabel newDay ) { if ( day != null ) { day.setForeground( DAYS_FOREGROUND ); day.setOpaque( false ); day.setBorder( EMPTY_BORDER ); } day = newDay; day.setForeground( SELECTED_DAY_FOREGROUND ); day.setOpaque( true ); if ( daysGrid.hasFocus() ) day.setBorder( FOCUSED_BORDER ); } /** * Sets the selected day. The day is specified as the number of * the day, in the month, to selected. The function compute the * corresponding control to select. * * @param newDay day to select **/ private void setSelected( int newDay ) { setSelected( days[(newDay+offset-1)/7+1][(newDay+offset-1)%7] ); } /** * Updates the calendar. This function updates the calendar panel * to reflect the month and year selected. It keeps the same day * of the month that was selected, except if it is beyond the last * day of the month. In this case, the last day of the month is * selected. **/ private void update() { int iday = getSelectedDay(); for ( int i=0; i<7; i++ ) { days[1][i].setText( " " ); days[5][i].setText( " " ); days[6][i].setText( " " ); } calendar.set( Calendar.DATE, 1 ); calendar.set( Calendar.MONTH, month.getSelectedIndex()+Calendar.JANUARY ); calendar.set( Calendar.YEAR, year.getSelectedIndex()+FIRST_YEAR ); offset = calendar.get(Calendar.DAY_OF_WEEK)-Calendar.SUNDAY; lastDay = calendar.getActualMaximum(Calendar.DATE); for ( int i=0; i<lastDay; i++ ) days[(i+offset)/7+1][(i+offset)%7].setText( String.valueOf(i+1) ); if ( iday != -1 ) { if ( iday > lastDay ) iday = lastDay; setSelected( iday ); } } /** * Called when the "Ok" button is pressed. Just sets a flag and * hides the dialog box. **/ public void actionPerformed( ActionEvent e ) { if ( e.getSource() == ok ) okClicked = true; setVisible(false); } /** * Called when the calendar gains the focus. Just re-sets the * selected day so that it is redrawn with the border that * indicate focus. **/ public void focusGained( FocusEvent e ) { setSelected( day ); } /** * Called when the calendar loses the focus. Just re-sets the * selected day so that it is redrawn without the border that * indicate focus. **/ public void focusLost( FocusEvent e ) { setSelected( day ); } /** * Called when a new month or year is selected. Updates the calendar * to reflect the selection. **/ public void itemStateChanged( ItemEvent e ) { update(); } /** * Called when a key is pressed and the calendar has the * focus. Handles the arrow keys so that the user can select a day * using the keyboard. **/ public void keyPressed( KeyEvent e ) { int iday = getSelectedDay(); switch ( e.getKeyCode() ) { case KeyEvent.VK_LEFT: if ( iday > 1 ) setSelected( iday-1 ); break; case KeyEvent.VK_RIGHT: if ( iday < lastDay ) setSelected( iday+1 ); break; case KeyEvent.VK_UP: if ( iday > 7 ) setSelected( iday-7 ); break; case KeyEvent.VK_DOWN: if ( iday <= lastDay-7 ) setSelected( iday+7 ); break; } } /** * Called when the mouse is clicked on a day in the * calendar. Selects the clicked day. **/ public void mouseClicked( MouseEvent e ) { JLabel day = (JLabel)e.getSource(); if ( !day.getText().equals(" ") ) setSelected( day ); daysGrid.requestFocus(); } public void keyReleased( KeyEvent e ) {} public void keyTyped( KeyEvent e ) {} public void mouseEntered( MouseEvent e ) {} public void mouseExited( MouseEvent e) {} public void mousePressed( MouseEvent e ) {} public void mouseReleased( MouseEvent e) {} /** * Constructs a new <code>DateChooser</code> with the given title. * * @param owner owner dialog * * @param title dialog title **/ public DateChooser( Dialog owner, String title ) { super( owner, title, true ); construct(); } /** * Constructs a new <code>DateChooser</code>. * * @param owner owner dialog **/ public DateChooser( Dialog owner ) { super( owner, true ); construct(); } /** * Constructs a new <code>DateChooser</code> with the given title. * * @param owner owner frame * * @param title dialog title **/ public DateChooser( Frame owner, String title ) { super( owner, title, true ); construct(); } /** * Constructs a new <code>DateChooser</code>. * * @param owner owner frame **/ public DateChooser( Frame owner ) { super( owner, true ); construct(); } /** * Selects a date. Displays the dialog box, with a given date as * the selected date, and allows the user select a new date. * * @param date initial date * * @return the new date selected or <code>null</code> if the user * press "Cancel" or closes the dialog box **/ public Date select( Date date ) { calendar.setTime( date ); int _day = calendar.get(Calendar.DATE); int _month = calendar.get(Calendar.MONTH); int _year = calendar.get(Calendar.YEAR); year.setSelectedIndex( _year-FIRST_YEAR ); month.setSelectedIndex( _month-Calendar.JANUARY ); setSelected( _day ); okClicked = false; setVisible(true); if ( !okClicked ) return null; calendar.set( Calendar.DATE, getSelectedDay() ); calendar.set( Calendar.MONTH, month.getSelectedIndex()+Calendar.JANUARY ); calendar.set( Calendar.YEAR, year.getSelectedIndex()+FIRST_YEAR ); return calendar.getTime(); } /** * Selects new date. Just calls {@link #select(Date)} with the * system date as the parameter. * * @return the same as the function {@link #select(Date)} **/ public Date select() { return select(new Date()); } }
