java - Swing Java 中的 Jcalendar

Question

//我正在 swing 中创建自定义 jcalender

//我遇到有关日期设置的问题//即实际月份从星期二开始，从星期三开始//我发现有关在日历模型中设置值的问题

//上面的代码运行良好，但在显示实际日期时出现问题//请建议我进行必要的更改

import java.awt.Color;


public class Calendar extends JFrame {

    private JPanel contentPane;

     String[] years = { "2008", "2009", "2010" ,"2011","2012","2013","2014"};

      JComboBox comboBox = new JComboBox(years);

      String[] months = { "January", "February", "March", "April", "May", "June", "July", "August",
          "September", "October", "November", "December" };

      JList list = new JList(months);

      JScrollPane scrollPane = new JScrollPane(list);

      CalendarModel model = new CalendarModel();

      JTable table = new JTable(model);

      public Calendar() {
            super();

            getContentPane().setLayout(null);
            comboBox.setBounds(10, 10, 100, 30);
            comboBox.setSelectedIndex(5);
            comboBox.addItemListener(new ComboHandler());
            scrollPane.setBounds(200, 10, 150, 100);
            list.setSelectedIndex(10);
            list.addListSelectionListener(new ListHandler());
            table.setBounds(10, 150, 550, 200);
            model.setMonth(comboBox.getSelectedIndex() + 1998, list.getSelectedIndex());
            getContentPane().add(comboBox);
            getContentPane().add(scrollPane);
            table.setGridColor(Color.black);
            table.setShowGrid(true);
            getContentPane().add(table);

            this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

            setSize(530,300);
            setVisible(true);


          }


    /**
     * Launch the application.
     */
    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {
            public void run() {
                try {
                    Calendar frame = new Calendar();
                    frame.setVisible(true);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
    }

    public class ComboHandler implements ItemListener {
        public void itemStateChanged(ItemEvent e) {
            System.out.println("ItemState change Method called ");
          model.setMonth(comboBox.getSelectedIndex() + 1998, list.getSelectedIndex());
          table.repaint();
        }
      }

      public class ListHandler implements ListSelectionListener {
        public void valueChanged(ListSelectionEvent e) {
          model.setMonth(comboBox.getSelectedIndex() + 1998, list.getSelectedIndex());
          table.repaint();
        }
      }
    }
    class CalendarModel extends AbstractTableModel {
      String[] days = { "Sun" , "Mon", "Tue", "Wed", "Thu", "Fri", "Sat" };

      int[] numDays = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };

      String[][] calendar = new String[7][7];

      public CalendarModel() {

          //setting name of days (mon,tues)
        for (int i = 0; i < days.length; ++i)
        {
            System.out.println("day[i] *** "+days[i]);
            calendar[0][i] = days[i];

        }
        for (int i = 1; i < 7; ++i){
          for (int j = 0; j < 7; ++j)
          {
              System.out.println("calendar[i][j] value i ** "+i +" j value "+ j );
            calendar[i][j] = " ";
          }
        }

      }

      public int getRowCount() {
        return 7;
      }

      public int getColumnCount() {
        return 7;
      }

      public Object getValueAt(int row, int column) {
          System.out.println("get Value at ** "+calendar[row][column]); 
        return calendar[row][column];
      }

      /*
      public void setValueAt(Object value, int row, int column) {
          System.out.println("set Value at ** "+(String) value);
        calendar[row][column] = (String) value;
      }*/

      public void setMonth(int year, int month) {
        for (int i = 1; i < 7; ++i)
        {
          for (int j = 0; j < 7; ++j)
          {
            calendar[i][j] = " ";
          }
        }
        java.util.GregorianCalendar cal = new java.util.GregorianCalendar();
        cal.set(year, month, 1);
        int offset = cal.get(java.util.GregorianCalendar.DAY_OF_WEEK) - 1;
        offset += 7;
        int num = daysInMonth(year, month);
        for (int i = 0; i < num; ++i) {
            System.out.println("offset *** "+Integer.toString(i+1));
          calendar[offset / 7][offset % 7] = Integer.toString(i+1);
          ++offset;
        }
      }

      public boolean isLeapYear(int year) {
          System.out.println("Is Leap Year *** ");
        if (year % 4 == 0)
          return true;
        return false;
      }

      public int daysInMonth(int year, int month) {
          System.out.println("day In month*** ");
        int days = numDays[month];
        if (month == 1 && isLeapYear(year))
          ++days;
        System.out.println("days *** "+days);
        return days;
      }

}

Answer 1

我不知道这些是否相关，但是......

public void itemStateChanged(ItemEvent e) {

    int index = comboBox.getSelectedIndex();
    System.out.println("index = " + index + "; " + (index + 1998));

    model.setMonth(comboBox.getSelectedIndex() + 1998, list.getSelectedIndex());
    table.repaint();
}

不会产生与组合框中列出的结果相匹配的结果。例如，如果您选择第一个值，它将等于 1998 ，不是2008

所以，如果我选择 2013从组合框中，我实际上得到 2003 .

当我将其更改为

public void itemStateChanged(ItemEvent e) {

    int index = comboBox.getSelectedIndex();
    System.out.println("index = " + index + "; " + (index + 2008));

    model.setMonth(comboBox.getSelectedIndex() + 2008, list.getSelectedIndex());
    table.repaint();
}

它给了我更好的结果。

我也变了

java.util.GregorianCalendar cal = new java.util.GregorianCalendar();

至

java.util.Calendar cal = java.util.Calendar.getInstance();

如果可能的话，您应该避免对用户日历系统做出假设...

我也会避免null布局也是如此;)

您还应该避免调用 table.repaint当您更改表模型时，请尝试使用 fireTableDataChanged来自setMonth内方法

我个人会将监听器添加到组合框和 JList在设置选定的索引之前，这将允许监听器为您更新模型...

您还需要修复您ListHandler以便它使用 2008相反 1998