问个swing问题

Question

     我用swing日期控件做了个选取日期的程序.叫MyCalender.java..当我选取某一天就返回当天字符串如20091202.在另一个文件里写了另一个swing我想当我点取这张页面的一个按钮button2我就处发一个事件,让我得到MyCalender,java返回的值..而那个button的促发事件的返回值是个void,( public void jButton2_actionPerformed(ActionEvent e) )我要怎么才能得到日期字符串并把它付值给一个方法..
说明一下.我要做一个程序.当我选取某一天的日期的时候.我就会把当天的安符串传给一个servlet.然后servlet会通过URLConnection连接找到某一天日期的文件.这样我就可以得到选取那天的全部文件并通过我写的swing下载了.
我就是不知道怎么把这个日期字符串传给servlet..希望各位指点一下

Answer 1

保存结果到类成员变量里面。随时取用。jButton2_actionPerformed？
用的什么可视化工具了？

Answer 2

我还是贴代码吧..这个是主swing..当我选取日期时就可以把值传给getFile 方法里的url
public class MyFirstFrame extends JFrame {
        JList list;        public static void main(String[] args) throws IOException {
                MyFirstFrame mf = new MyFirstFrame();
                mf.setVisible(true);
        }        public MyFirstFrame() throws HeadlessException {
                super();
                try {
                        jbInit();
                } catch (Exception ex) {
                        ex.printStackTrace();
                }
        }        public MyFirstFrame(GraphicsConfiguration gc) {
                super(gc);
        }        public MyFirstFrame(String title) throws HeadlessException {
                super(title);
        }        public MyFirstFrame(String title, GraphicsConfiguration gc) {
                super(title, gc);
        }        BorderLayout borderLayout1 = new BorderLayout();
        JPanel jPanel1 = new JPanel();
    JButton jButton1 = new JButton();
    JButton jButton2 = new JButton();    private void jbInit() throws Exception {
                this.getContentPane().setLayout(borderLayout1);
                this.getContentPane().setBackground(SystemColor.inactiveCaption);
        this.addHierarchyBoundsListener(new
                MyFirstFrame_this_hierarchyBoundsAdapter(this));
        jPanel1.setBackground(Color.lightGray);
                jPanel1.setMinimumSize(new Dimension(52, 20));
                jPanel1.setPreferredSize(new Dimension(10, 30));
        jButton1.setAlignmentX((float) 1.0);
                jButton1.setAlignmentY((float) 1.0);
                jButton1.setBorder(BorderFactory.createLoweredBevelBorder());
                jButton1.setPreferredSize(new Dimension(22, 23));
                jButton1.setToolTipText("");
                jButton1.setHorizontalTextPosition(SwingConstants.CENTER);
                jButton1.setMnemonic('0');
                jButton1.setText("下载");
                jButton1.addActionListener(new MyFirstFrame_jButton1_actionAdapter(this));                
                UrlCon co = new UrlCon();
                List l = co.getFile();
                for (int i = 0; i < l.size(); i++) {
                        if (l.get(i).equals("WEB-INF")) {
                                l.remove(i);
                        }
                }
                Object[] str = new Object[l.size()];
                str = l.toArray();
                final DefaultListModel model = new DefaultListModel();
                for (int i = 0, n = str.length; i < n; i++) {
                        model.addElement(str[i]);
                }
                list = new JList(model);
                setSize(600, 400);
        jButton2.setForeground(Color.red);
        jButton2.setToolTipText("");
        jButton2.setText("请选择日期");
        jButton2.addActionListener(new MyFirstFrame_jButton2_actionAdapter(this));
        this.getContentPane().add(jButton1, java.awt.BorderLayout.SOUTH);
                //this.getContentPane().add(list, java.awt.BorderLayout.CENTER);
                this.getContentPane().add(new JScrollPane(list), java.awt.BorderLayout.CENTER);
        this.getContentPane().add(jPanel1, java.awt.BorderLayout.NORTH);
        jPanel1.add(jButton2);
    }
事件按钮
 public void jButton2_actionPerformed(ActionEvent e) {
     JFrame frame = new JFrame("Calendar Application"); 
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
        MyCalendar myCalendar = new MyCalendar(); 
        myCalendar.init(); 
        frame.getContentPane().add(myCalendar); 
        frame.setSize(240, 172); 
        frame.show(); 
       
    }
class UrlCon{
 public ArrayList getFile() throws IOException {
                ArrayList l = new ArrayList();
                try {
                        //URL url = new URL("http://localhost:8080/ftpdowns/MyServlet");
                        //URL url=new URL("http://136.5.68.7:8080/creport/files/20091130/xlsfiles/");
                        URL url=new URL("http://136.5.68.7:8080/creport/filelist?dir=20091130");
                        HttpURLConnection urlcon = (HttpURLConnection) url.openConnection();
                        // urlcon.setDoOutput(true);
                        // urlcon.setDoInput(true);
                        urlcon.connect();
                        BufferedReader in = new BufferedReader(new InputStreamReader(urlcon
                                        .getInputStream()));
                        String inputLine;
                        /*
                        while ((inputLine = in.readLine()) != null) {
                                if(inputLine.substring(0, 2).equals("<a")){
                                        String regex="(CDMA.*?xls)"; 
                                        Pattern p= Pattern.compile(regex);
                                         Matcher m= p.matcher(inputLine);
                                         while (m.find()) { 
                                                 if(decode(m.group()).substring(0, 5).equals("CDMA网"))
                                                         l.add(decode(m.group()));                                               }     
                                }
                        }
                        */
                        while ((inputLine = in.readLine()) != null) {
                                l.add(inputLine);
                        }
                } catch (MalformedURLException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                }
                return l;
}}

Answer 3

当我选取某一天时就会返回当天日期字符串
package com.ui;import java.awt.*;
import java.awt.event.*;
import java.util.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.table.*;public class MyCalendar extends JApplet {    public static final String WEEK_SUN = "日";    public static final String WEEK_MON = "一";    public static final String WEEK_TUE = "二";    public static final String WEEK_WED = "三";    public static final String WEEK_THU = "四";    public static final String WEEK_FRI = "五";    public static final String WEEK_SAT = "六";    public static final Color background = Color.white;    public static final Color foreground = Color.black;    public static final Color headerBackground = Color.blue;    public static final Color headerForeground = Color.white;    public static final Color selectedBackground = Color.blue;    public static final Color selectedForeground = Color.white;
    String date;    private JPanel cPane;    private JLabel yearsLabel;    private JSpinner yearsSpinner;    private JLabel monthsLabel;    private JComboBox monthsComboBox;    private JTable daysTable;    private AbstractTableModel daysModel;    private Calendar calendar;    private String value;
        public String getDate() {
return date;
} public void setDate(String date) {
this.date = date;
} public String getValue() {
        return this.value;
    }    public MyCalendar() {
        cPane = (JPanel) getContentPane();
    }    public void init() {
        cPane.setLayout(new BorderLayout());        calendar = Calendar.getInstance();
        calendar = Calendar.getInstance();
        yearsLabel = new JLabel("年: ");
        yearsSpinner = new JSpinner();
        yearsSpinner.setEditor(new JSpinner.NumberEditor(yearsSpinner, "0000"));
        yearsSpinner.setValue(new Integer(calendar.get(Calendar.YEAR)));
        yearsSpinner.addChangeListener(new ChangeListener() {
            public void stateChanged(ChangeEvent changeEvent) {
                int day = calendar.get(Calendar.DAY_OF_MONTH);
                calendar.set(Calendar.DAY_OF_MONTH, 1);
                calendar.set(Calendar.YEAR, ((Integer) yearsSpinner.getValue())
                        .intValue());
                int maxDay = calendar.getActualMaximum(Calendar.DAY_OF_MONTH);
                calendar
                        .set(Calendar.DAY_OF_MONTH, day > maxDay ? maxDay : day);
                updateView();
            }
        });        JPanel yearMonthPanel = new JPanel();
        cPane.add(yearMonthPanel, BorderLayout.NORTH);
        yearMonthPanel.setLayout(new BorderLayout());
        yearMonthPanel.add(new JPanel(), BorderLayout.CENTER);
        JPanel yearPanel = new JPanel();
        yearMonthPanel.add(yearPanel, BorderLayout.WEST);
        yearPanel.setLayout(new BorderLayout());
        yearPanel.add(yearsLabel, BorderLayout.WEST);
        yearPanel.add(yearsSpinner, BorderLayout.CENTER);        monthsLabel = new JLabel("月: ");
        monthsComboBox = new JComboBox();
        for (int i = 1; i <= 12; i++) {
            monthsComboBox.addItem(new Integer(i));
        }
        monthsComboBox.setSelectedIndex(calendar.get(Calendar.MONTH));
        monthsComboBox.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent actionEvent) {
                int day = calendar.get(Calendar.DAY_OF_MONTH);
                calendar.set(Calendar.DAY_OF_MONTH, 1);
                calendar.set(Calendar.MONTH, monthsComboBox.getSelectedIndex());
                int maxDay = calendar.getActualMaximum(Calendar.DAY_OF_MONTH);
                calendar
                        .set(Calendar.DAY_OF_MONTH, day > maxDay ? maxDay : day);
                updateView();
            }
        });
        JPanel monthPanel = new JPanel();
        yearMonthPanel.add(monthPanel, BorderLayout.EAST);
        monthPanel.setLayout(new BorderLayout());
        monthPanel.add(monthsLabel, BorderLayout.WEST);
        monthPanel.add(monthsComboBox, BorderLayout.CENTER);        daysModel = new AbstractTableModel() {
            public int getRowCount() {
                return 7;
            }            public int getColumnCount() {
                return 7;
            }            public Object getValueAt(int row, int column) {
                if (row == 0) {
                    return getHeader(column);
                }
                row--;
                Calendar calendar = (Calendar) MyCalendar.this.calendar.clone();
                calendar.set(Calendar.DAY_OF_MONTH, 1);
                int dayCount = calendar.getActualMaximum(Calendar.DAY_OF_MONTH);
                int moreDayCount = calendar.get(Calendar.DAY_OF_WEEK) - 1;
                int index = row * 7 + column;
                int dayIndex = index - moreDayCount + 1;
                if (index < moreDayCount || dayIndex > dayCount) {
                    return null;
                } else {
                    return new Integer(dayIndex);
                }
            }
        };        daysTable = new CalendarTable(daysModel, calendar);
        daysTable.setCellSelectionEnabled(true);
        daysTable.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);        daysTable.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseClicked(java.awt.event.MouseEvent e) {
                if (e.getClickCount() == 2) {
                    Object o = daysTable.getValueAt(daysTable.getSelectedRow(),
                            daysTable.getSelectedColumn());
                    if (o != null) {
                        // 不是点在空的格子，赋值
                        value = yearsSpinner.getValue()
                                + monthsComboBox.getSelectedItem().toString()
                                + o;
                        System.out.println(value);
                   
                       
                    } else {
                        // 否则清空
                        value = "";
                    }                }
            }
        });
        daysTable.setDefaultRenderer(daysTable.getColumnClass(0),
                new TableCellRenderer() {
                    public Component getTableCellRendererComponent(
                            JTable table, Object value, boolean isSelected,
                            boolean hasFocus, int row, int column) {
                        String text = (value == null) ? "" : value.toString();
                        JLabel cell = new JLabel(text);
                        cell.setOpaque(true);
                        if (row == 0) {
                            cell.setForeground(headerForeground);
                            cell.setBackground(headerBackground);
                        } else {
                            if (isSelected) {
                                cell.setForeground(selectedForeground);
                                cell.setBackground(selectedBackground);
                            } else {
                                cell.setForeground(foreground);
                                cell.setBackground(background);
                            }
                        }                        return cell;
                    }
                });
        updateView();        cPane.add(daysTable, BorderLayout.CENTER);
    }    public static String getHeader(int index) {
        switch (index) {
        case 0:
            return WEEK_SUN;
        case 1:
            return WEEK_MON;
        case 2:
            return WEEK_TUE;
        case 3:
            return WEEK_WED;
        case 4:
            return WEEK_THU;
        case 5:
            return WEEK_FRI;
        case 6:
            return WEEK_SAT;
        default:
            return null;
        }
    }    public void updateView() {
        daysModel.fireTableDataChanged();
        daysTable.setRowSelectionInterval(calendar.get(Calendar.WEEK_OF_MONTH),
                calendar.get(Calendar.WEEK_OF_MONTH));
        daysTable.setColumnSelectionInterval(
                calendar.get(Calendar.DAY_OF_WEEK) - 1, calendar
                        .get(Calendar.DAY_OF_WEEK) - 1);
    }    public static class CalendarTable extends JTable {
        private Calendar calendar;        public CalendarTable(TableModel model, Calendar calendar) {
            super(model);
            this.calendar = calendar;
        }        public void changeSelection(int row, int column, boolean toggle,
                boolean extend) {
            super.changeSelection(row, column, toggle, extend);
            if (row == 0) {
                return;
            }
            Object obj = getValueAt(row, column);
            if (obj != null) {
                calendar.set(Calendar.DAY_OF_MONTH, ((Integer) obj).intValue());
            }
        }    }    public static void main(String[] args) {
        JFrame frame = new JFrame("Calendar Application");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        MyCalendar myCalendar = new MyCalendar();
        myCalendar.init();
        frame.getContentPane().add(myCalendar);
        frame.setSize(240, 172);
        frame.show();    }}

Answer 4

但看代码是c/s结构，而你为什么要传给servlet，这样到底是c/s还是b/s结构了？

Answer 5

传给servlet是为了获得tomcat文件夹下的文件列表....
界面是用swing做的

Answer 6

要传的办法也有啊，例如socket，或者整一个临时公共文件（session不知道行不行，没试过）

Answer 7

请问，你是要在这个地方打开日期选择的控件？并且获取日期？
因为没看到你在那里使用这个方法，哪个按钮触发，所以我很奇怪。而且按钮的ACtion监听好像这样也触发不了。说句闲话，frame.show();已经过时，jdk推荐不使用。用setVisible(true);

Answer 8

就是在那里获得日期控件的..因为以前没做过swing所以有很多问题不明白.还需要改哪里希望指点一下..谢谢

Answer 9

难道不能用button去触发事件...那该用什么

Answer 10

点击button的时候是触发一个事件，这个事件是发给EventQueue的。所以不存在返回值。别在这个上面浪费时间了。
java有一个现成的颜色选择控件：JColorChooser，它的功能和你说的这个比较类似。你可以去看看它的源代码。
一般这样用：
Color c = JColorChooser.showDialog(component, "JColorChooser", new Color(255,0,0));
弹出一个选择颜色的对话框，你选择一个颜色，点确定以后，返回一个你选择的那个颜色。
另外，我们常用的还有一种方法：
JOptionPane.showOptionDialog
它也是弹出一个模态对话框，等你选择一个东西选项后，返回你选择的值给你。
但是你要注意，这两个方法都是静态方法，它内部可能是通过消息来传递值。

Answer 11

swing不太懂，进来学习，顺便接分

Answer 12

这跟是不是使用Swing没有太大关系。
呃……你的日期控件是一个JApplet ？虽说也行，但是，一般这样的情形，放一个JDialog比较好吧。
那就不需要你再套一层窗口了。
你等一下吧，我写小一段代码。你看了就明白，不然敲键盘手指头疼了也未必能说明白哦

Answer 13

    public static Color showDialog(Component component,
        String title, Color initialColor) throws HeadlessException {        final JColorChooser pane = new JColorChooser(initialColor != null?
                                               initialColor : Color.white);        ColorTracker ok = new ColorTracker(pane);
        JDialog dialog = createDialog(component, title, true, pane, ok, null);        dialog.show(); // blocks until user brings dialog down...        return ok.getColor();
    }
我把JColorChooser#showDialog代码贴出来，你可以借鉴一下。
注意这里：
        ColorTracker ok = new ColorTracker(pane);
        JDialog dialog = createDialog(component, title, true, pane, ok, null);
把ok作为一个参数传递个了dialog，dialog中对ok的颜色进行set。
最后把ok中的value取出来，作为返回值。

Answer 14

我把你的代码作了修改。你的MyFirstFrame我就不管了。我用了你这个名字但是我只放了一个按钮。
我不多说了。代码放在这里，你自己看。当然有更好的方法，我就先不说了，封装的方法也不唯一。你慢慢摸索就是。
另，你说是web，我就没有使用静态存实例，每次new MyCalendar出来。ie6中使用静态的是有问题，firefox没发现，其他没试。日期控件那个类我进行了修改，关注一下构造函数，继承的基类。
个人认为与其说些乱七八糟的话倒是不如动手做写实实在在的工作。
多说无益，代码附下：import java.awt.*;
import java.awt.event.*;
import java.util.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.table.*;public class MyCalendar extends JDialog { public static final String WEEK_SUN = "日"; public static final String WEEK_MON = "一"; public static final String WEEK_TUE = "二"; public static final String WEEK_WED = "三"; public static final String WEEK_THU = "四"; public static final String WEEK_FRI = "五"; public static final String WEEK_SAT = "六"; public static final Color background = Color.white; public static final Color foreground = Color.black; public static final Color headerBackground = Color.blue; public static final Color headerForeground = Color.white; public static final Color selectedBackground = Color.blue; public static final Color selectedForeground = Color.white;
String date; private JPanel cPane; private JLabel yearsLabel; private JSpinner yearsSpinner; private JLabel monthsLabel; private JComboBox monthsComboBox; private JTable daysTable; private AbstractTableModel daysModel; private Calendar calendar; private String value; public String getDate() {
return date;
} public void setDate(String date) {
this.date = date;
} public String getValue() {
return this.value;
} public MyCalendar() {
cPane = (JPanel) getContentPane();
setSize(new Dimension(400, 200));
setModal(true);
setDefaultCloseOperation(DISPOSE_ON_CLOSE);
init();
} public void init() {
cPane.setLayout(new BorderLayout()); calendar = Calendar.getInstance();
calendar = Calendar.getInstance();
yearsLabel = new JLabel("年: ");
yearsSpinner = new JSpinner();
yearsSpinner.setEditor(new JSpinner.NumberEditor(yearsSpinner, "0000"));
yearsSpinner.setValue(new Integer(calendar.get(Calendar.YEAR)));
yearsSpinner.addChangeListener(new ChangeListener() {
public void stateChanged(ChangeEvent changeEvent) {
int day = calendar.get(Calendar.DAY_OF_MONTH);
calendar.set(Calendar.DAY_OF_MONTH, 1);
calendar.set(Calendar.YEAR, ((Integer) yearsSpinner.getValue())
.intValue());
int maxDay = calendar.getActualMaximum(Calendar.DAY_OF_MONTH);
calendar
.set(Calendar.DAY_OF_MONTH, day > maxDay ? maxDay : day);
updateView();
}
}); JPanel yearMonthPanel = new JPanel();
cPane.add(yearMonthPanel, BorderLayout.NORTH);
yearMonthPanel.setLayout(new BorderLayout());
yearMonthPanel.add(new JPanel(), BorderLayout.CENTER);
JPanel yearPanel = new JPanel();
yearMonthPanel.add(yearPanel, BorderLayout.WEST);
yearPanel.setLayout(new BorderLayout());
yearPanel.add(yearsLabel, BorderLayout.WEST);
yearPanel.add(yearsSpinner, BorderLayout.CENTER); monthsLabel = new JLabel("月: ");
monthsComboBox = new JComboBox();
for (int i = 1; i <= 12; i++) {
monthsComboBox.addItem(new Integer(i));
}
monthsComboBox.setSelectedIndex(calendar.get(Calendar.MONTH));
monthsComboBox.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent actionEvent) {
int day = calendar.get(Calendar.DAY_OF_MONTH);
calendar.set(Calendar.DAY_OF_MONTH, 1);
calendar.set(Calendar.MONTH, monthsComboBox.getSelectedIndex());
int maxDay = calendar.getActualMaximum(Calendar.DAY_OF_MONTH);
calendar
.set(Calendar.DAY_OF_MONTH, day > maxDay ? maxDay : day);
updateView();
}
});
JPanel monthPanel = new JPanel();
yearMonthPanel.add(monthPanel, BorderLayout.EAST);
monthPanel.setLayout(new BorderLayout());
monthPanel.add(monthsLabel, BorderLayout.WEST);
monthPanel.add(monthsComboBox, BorderLayout.CENTER); daysModel = new AbstractTableModel() {
public int getRowCount() {
return 7;
} public int getColumnCount() {
return 7;
} public Object getValueAt(int row, int column) {
if (row == 0) {
return getHeader(column);
}
row--;
Calendar calendar = (Calendar) MyCalendar.this.calendar.clone();
calendar.set(Calendar.DAY_OF_MONTH, 1);
int dayCount = calendar.getActualMaximum(Calendar.DAY_OF_MONTH);
int moreDayCount = calendar.get(Calendar.DAY_OF_WEEK) - 1;
int index = row * 7 + column;
int dayIndex = index - moreDayCount + 1;
if (index < moreDayCount || dayIndex > dayCount) {
return null;
} else {
return new Integer(dayIndex);
}
}
}; daysTable = new CalendarTable(daysModel, calendar);
daysTable.setCellSelectionEnabled(true);
daysTable.setSelectionMode(ListSelectionModel.SINGLE_SELECTION); daysTable.addMouseListener(new java.awt.event.MouseAdapter() {
public void mouseClicked(java.awt.event.MouseEvent e) {
if (e.getClickCount() == 2) {
Object o = daysTable.getValueAt(daysTable.getSelectedRow(),
daysTable.getSelectedColumn());
if (o != null) {
// 不是点在空的格子，赋值
value = yearsSpinner.getValue()
+ monthsComboBox.getSelectedItem().toString()
+ o;
// System.out.println(value); } else {
// 否则清空
value = "";
} dispose();
}
}
});
daysTable.setDefaultRenderer(daysTable.getColumnClass(0),
new TableCellRenderer() {
public Component getTableCellRendererComponent(
JTable table, Object value, boolean isSelected,
boolean hasFocus, int row, int column) {
String text = (value == null) ? "" : value.toString();
JLabel cell = new JLabel(text);
cell.setOpaque(true);
if (row == 0) {
cell.setForeground(headerForeground);
cell.setBackground(headerBackground);
} else {
if (isSelected) {
cell.setForeground(selectedForeground);
cell.setBackground(selectedBackground);
} else {
cell.setForeground(foreground);
cell.setBackground(background);
}
} return cell;
}
});
updateView(); cPane.add(daysTable, BorderLayout.CENTER);
} public static String getHeader(int index) {
switch (index) {
case 0:
return WEEK_SUN;
case 1:
return WEEK_MON;
case 2:
return WEEK_TUE;
case 3:
return WEEK_WED;
case 4:
return WEEK_THU;
case 5:
return WEEK_FRI;
case 6:
return WEEK_SAT;
default:
return null;
}
} public void updateView() {
daysModel.fireTableDataChanged();
daysTable.setRowSelectionInterval(calendar.get(Calendar.WEEK_OF_MONTH),
calendar.get(Calendar.WEEK_OF_MONTH));
daysTable.setColumnSelectionInterval(
calendar.get(Calendar.DAY_OF_WEEK) - 1, calendar
.get(Calendar.DAY_OF_WEEK) - 1);
} public static class CalendarTable extends JTable {
private Calendar calendar; public CalendarTable(TableModel model, Calendar calendar) {
super(model);
this.calendar = calendar;
} public void changeSelection(int row, int column, boolean toggle,
boolean extend) {
super.changeSelection(row, column, toggle, extend);
if (row == 0) {
return;
}
Object obj = getValueAt(row, column);
if (obj != null) {
calendar.set(Calendar.DAY_OF_MONTH, ((Integer) obj).intValue());
}
} }}import java.awt.Container;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;import javax.swing.JButton;
import javax.swing.JFrame;public class MyFirstFrame extends JFrame { private static final long serialVersionUID = 1L; private String selectedDate = ""; public MyFirstFrame() {
super(); Container c = getContentPane();
c.setLayout(new FlowLayout());
JButton b = new JButton("Date select");
c.add(b); b.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
MyCalendar ca = new MyCalendar();
// some calendar init work here
ca.setVisible(true); selectedDate = ca.getValue();
System.out.println(selectedDate);
}
}); setSize(600, 400);
setDefaultCloseOperation(EXIT_ON_CLOSE);
setLocationRelativeTo(null);
setVisible(true);
} public static void main(String[] args) {
new MyFirstFrame();
}
}

Answer 15

以上，MyFirstFrame 中的selectedDate 就有值了，你可以随意使用。
其他的传递等等工作，我就不了解了。按照需要去做吧。

Answer 16

在MyFirstFrame类中添加个成员变量strDate记录选择的日期值
之后传递给UrlCon类的getFile方法就可以了
你的程序还是有些问题，
UrlCon co = new UrlCon();List l = co.getFile(); 应该放到下载按钮的事件中
public class MyFirstFrame extends JFrame { 
    private strDate = null;
    ……
    //strDate = 选择的日期;按照16楼的方法得到日期值
    UrlCon co = new UrlCon();
    List l = co.getFile(strDate); 
}
class UrlCon{
public ArrayList getFile(String strDate) throws IOException {
                ArrayList l = new ArrayList();
                try {
                        URL url=new URL("http://136.5.68.7:8080/creport/filelist?dir="+strDate);
                        ……
                }catch(Exception e){
                }
}
}