SWT实现弹出日历控件

实现像网页上的那种用户单击一个Text框然后框下面出现一个日历控件，点击Text框以外的地方日历消失，怎么实现？

import
 org.eclipse.swt.SWT;
import
 org.eclipse.swt.events.MouseAdapter;
import
 org.eclipse.swt.events.MouseEvent;
import
 org.eclipse.swt.graphics.Color;
import
 org.eclipse.swt.graphics.Point;
import
 org.eclipse.swt.widgets.Display;
import
 org.eclipse.swt.widgets.Shell;
import
 org.eclipse.swt.widgets.Text;

public
 
class
 DateTimeDemo 
extends
 Shell
{
    private
 
static
 Display display;

    private
 Text text;

    public
 
static
 
void
 main(String args[])
    {
        try
        {
            display = Display.getDefault();
            DateTimeDemo shell = new
 DateTimeDemo(display, SWT.SHELL_TRIM);
            shell.open();
            shell.layout();

            while
(!shell.isDisposed())
            {
                if
(!display.readAndDispatch())
                {
                    display.sleep();
                }
            }

            display.dispose();
        }
        catch
(Exception e)
        {
            e.printStackTrace();
        }
    }

    public
 DateTimeDemo(Display display, 
int
 style)
    {
        super
(display, style);
        createContents();
    }

    protected
 
void
 createContents()
    {
        setText("DateTime"
);
        setSize(471
, 
140
);
        text = new
 Text(
this
, SWT.BORDER);
        text.setEditable(false
);
        text.setBackground(new
 Color(display, 
255
, 
255
, 
255
));
        text.setBounds(122
, 
41
, 
228
, 
25
);

        text.addMouseListener(new
 MouseAdapter()
        {
            public
 
void
 mouseUp(MouseEvent e)
            {
                DTDialog dialog = DTDialog.getInstance(DateTimeDemo.this
);
                dialog.open();
            }
        });
    }

    public
 Point getDtLocation()
    {
        return
 
new
 Point(text.getLocation().x + DateTimeDemo.
this
.getLocation().x,
                        text.getLocation().y + DateTimeDemo.this
.getLocation().y + 
60
);
    }

    public
 
void
 setDate(String str)
    {
        text.setText(str);
    }

    @Override
    protected
 
void
 checkSubclass()
    {
    // Disable the check that prevents subclassing of SWT components
    }
}

 

import
 org.eclipse.swt.SWT;
import
 org.eclipse.swt.events.FocusAdapter;
import
 org.eclipse.swt.events.FocusEvent;
import
 org.eclipse.swt.events.SelectionAdapter;
import
 org.eclipse.swt.events.SelectionEvent;
import
 org.eclipse.swt.layout.FillLayout;
import
 org.eclipse.swt.widgets.DateTime;
import
 org.eclipse.swt.widgets.Dialog;
import
 org.eclipse.swt.widgets.Display;
import
 org.eclipse.swt.widgets.Shell;

public
 
class
 DTDialog 
extends
 Dialog
{
    private
 Object result;

    private
 Shell shell;

    private
 DateTime dateTime;

    private
 DateTimeDemo parent;

    private
 
static
 DTDialog instance;

    public
 
static
 DTDialog getInstance(DateTimeDemo parent)
    {
        if
(instance == 
null
)
        {
            instance = new
 DTDialog(parent);
        }

        return
 instance;
    }

    private
 DTDialog(DateTimeDemo parent)
    {
        super
(parent, SWT.NO_TRIM);
        this
.parent = parent;
    }

    public
 Object open()
    {
        if
(shell == 
null
 || shell.isDisposed())
        {
            createContents();
            shell.open();
            shell.layout();
            Display display = getParent().getDisplay();

            while
(!shell.isDisposed())
            {
                if
(!display.readAndDispatch())
                {
                    display.sleep();
                }
            }

            display.dispose();
        }
        else
        {
            shell.setLocation(parent.getDtLocation());
            shell.setVisible(true
);
            shell.setFocus();
        }

        return
 result;
    }

    protected
 
void
 createContents()
    {
        shell = new
 Shell(getParent(), SWT.NO_TRIM);
        shell.setLayout(new
 FillLayout());
        shell.setSize(272
, 
140
);
        shell.setLocation(parent.getDtLocation());
        shell.setText("SWT Dialog"
);
        dateTime = new
 DateTime(shell, SWT.CALENDAR);

        dateTime.addSelectionListener(new
 SelectionAdapter()
        {
            public
 
void
 widgetSelected(SelectionEvent e)
            {
                parent.setDate(formatDt());
            }
        });

        dateTime.addFocusListener(new
 FocusAdapter()
        {
            public
 
void
 focusLost(FocusEvent e)
            {
                parent.setDate(formatDt());
                shell.setVisible(false
);
            }
        });
    }

    private
 String formatDt()
    {
        return
 dateTime.getYear() + 
"-"
 + dateTime.getMonth() + 
"-"
 + dateTime.getDay();
    }

    public
 Shell getShell()
    {
        return
 shell;
    }
}