Question

我想使它具有适应性，例如2月在2000年有29天，但是到2001年它将变为28天。

我想在使用JComboBox

时这样做

如何使用组合框制作活动日历？

    JComboBox jcb,jcb1,jcb2;    
    db(){
    JFrame jf = new JFrame("register");
    jf.setLayout=(new FlowLayout());
    DateTimeFormatter dtf = DateTimeFormatter.ofPattern("dd-MM-yyyy");
    String aa1="0"+1+"-"+"0"+2+"-"+2000;
    date = LocalDate.parse(aa1,dtf);
    Integer day[] = new Integer[date.lengthOfMonth()];
    for(int i=0;i<date.lengthOfMonth();i++) {
        day[i]=i+1;
    }
    jcb = new JComboBox<>(day);
    Integer month[] = new Integer[12];
    for(int i=0;i<12;i++) {
        month[i]=i+1;
    }
    jcb1 = new JComboBox<>(month);

    Integer year[] = new Integer[80];
    for(int i=0;i<80;i++) {
        year[i]=i+1940;
    }
    jcb2 = new JComboBox<>(year);
    jf.add(jcb);
    jf.add(jcb1);
    jf.add(jcb2);
    jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    jf.setBounds(300,300,300,300);
    jf.setVisible(true);
}

Answer 1

正如@Andrew Thompson在评论中提到的那样，用于日期选择的JComboBoxes不是一个好主意。看看Which one is the best Java datepicker.

但是，如果您仍然坚持使用组合框，则要实现所需的功能，就必须在月/年组合框中添加public class Test extends JFrame implements ActionListener { private JComboBox<Integer> yearBox; private JComboBox<Integer> monthBox; private JComboBox<Integer> dayBox; public Test() { super("test"); setDefaultCloseOperation(EXIT_ON_CLOSE); getContentPane().setLayout(new FlowLayout()); yearBox = new JComboBox<>(); for (int i = 1940; i <= LocalDateTime.now().getYear(); i++) { yearBox.addItem(i); } yearBox.addActionListener(this); monthBox = new JComboBox<>(); for (int i = 1; i <= 12; i++) { monthBox.addItem(i); } monthBox.addActionListener(this); dayBox = new JComboBox<>(); add(new JLabel("year:")); add(yearBox); add(new JLabel("month:")); add(monthBox); add(new JLabel("day:")); add(dayBox); //Start with current year selected yearBox.setSelectedIndex(yearBox.getItemCount() - 1); setSize(400, 400); setLocationRelativeTo(null); } @Override public void actionPerformed(ActionEvent e) { int year = (int) yearBox.getSelectedItem(); int month = (int) monthBox.getSelectedItem(); int daysInThisMonth = LocalDate.of(year, month, 1).lengthOfMonth(); int previousSelection = dayBox.getSelectedItem() != null ? (int) dayBox.getSelectedItem() : 1; dayBox.removeAllItems(); for (int i = 1; i <= daysInThisMonth; i++) { dayBox.addItem(i); } if (previousSelection >= dayBox.getItemCount()) //select last index of month dayBox.setSelectedIndex(dayBox.getItemCount() - 1); else dayBox.setSelectedItem(previousSelection); } public static void main(String[] args) { SwingUtilities.invokeLater(() -> new Test().setVisible(true)); } }，以便重新确定天数的模型（项目）组合框。

看看这个例子：

declare cur cursor for Select TableName From TABLE_LIST
declare @tablename nvarchar(max)
declare @sqlstring nvarchar(max)

open cur
fetch next from cur into @tablename
while @@fetch_status=0
  begin
    set @sqlstring = 'SELECT ''' + @tablename + ''' AS ''TABLE'', [LAST_REFRESHED] FROM ' + @tablename
    exec sp_executesql @sqlstring
    fetch next from cur into @tablename
  end
close cur
deallocate cur
;

如何使用JComboBox制作日历？

1 个答案: