JSpinner 跳跃数周而不是数天

Question

我创建了一个 JSpinner 对象，它每天上下移动，点击时跳过周末。然后我添加了一个功能，如果你在周六或周日打开程序，它应该回滚到周五。问题不是改为星期五，而是 JSpinner 跳回一周。

我尝试在新程序中隔离问题，但没有成功。代码应该完全相同，所以我不确定是什么导致了这个问题。

import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.text.DecimalFormat;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import javax.annotation.PostConstruct;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JSpinner;
import javax.swing.SpinnerDateModel;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
@SuppressWarnings("serial")
public class MainFrame extends JFrame {

DecimalFormat df = new DecimalFormat("#.00");
SpinnerDateModel spinnerModel;
JSpinner spinner;
Integer loopStep;
Integer firstloopStep = 0;

MainFrame() {
    super("Spinner Control");

    setLayout(new BorderLayout());

    JPanel panel1 = new JPanel();
    JPanel panelNorth = new JPanel();

    // spinner for date information
    spinnerModel = new SpinnerDateModel();
    spinnerModel.setCalendarField(Calendar.WEEK_OF_MONTH);
    spinner = new JSpinner(spinnerModel);
    JSpinner.DateEditor editor = new JSpinner.DateEditor(spinner, "EEEEE, dd MMMMM, yyyy");
    spinner.setEditor(editor);

    // add panels/buttons/etc to page
    add(panel1, BorderLayout.PAGE_START);
    panel1.setPreferredSize(new Dimension(1280, 100));
    panelNorth.setPreferredSize(new Dimension(1280, 40));

    panel1.add(panelNorth, BorderLayout.NORTH);
    panelNorth.add(spinner, BorderLayout.PAGE_START);

    //method executes on start up
    skipWeekends();

    loopStep = 0;
    //rotate the date, skip weekends, works fine here
    spinner.addChangeListener(new ChangeListener() {
        @Override
        public void stateChanged(ChangeEvent arg0) {
            Date date = (Date) spinner.getValue();
            System.out.println("todays date " + date);
            SimpleDateFormat sdf = new SimpleDateFormat("EEEEE, dd MMMMM, yyyy");
            String stringDate = sdf.format(date);
            System.out.println(stringDate);
            char c = stringDate.charAt(0);
            char c2 = stringDate.charAt(1);

            //skip the weekends
            if ((c == 'S') && (c2 == 'a') && (loopStep == 0)) {
                loopStep = 1;
                spinner.setValue(spinner.getNextValue());
                spinner.setValue(spinner.getNextValue());
                System.out.println("Saturday Spinner going back 2");
            }

            if ((c == 'S') && (c2 == 'u') && (loopStep == 0)) {
                loopStep = 1;
                spinner.setValue(spinner.getPreviousValue());
                spinner.setValue(spinner.getPreviousValue());
                System.out.println("Sunday Spinner going back 2");
            }
            if (loopStep == 1) {
                loopStep = 2;
            }
            if (loopStep == 2) {
                loopStep = 0;
            }


        }
    });


    setExtendedState(MAXIMIZED_BOTH);
    setMinimumSize(new Dimension(1280, 485));
    setSize(640, 485);
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    setVisible(true);

}

@PostConstruct
private void skipWeekends(){
    //skips weekends when program opens, skips weeks for some reason
    Date date = (Date) spinner.getValue();
    System.out.println("todays date " + date);
    SimpleDateFormat sdf = new SimpleDateFormat("EEEEE, dd MMMMM, yyyy");
    String stringDate = sdf.format(date);
    System.out.println(stringDate);
    char c = stringDate.charAt(0);
    char c2 = stringDate.charAt(1);

    if ((c == 'S') && (c2 == 'a')) {

        spinner.setValue(spinner.getPreviousValue());
        System.out.println("Saturday Spinner going back 2");
    }

    if ((c == 'S') && (c2 == 'u')) {

        spinner.setValue(spinner.getPreviousValue());
        spinner.setValue(spinner.getPreviousValue());
        System.out.println("Sunday Spinner going back 2");
    }


}

}

Answer 1

您正在将 SpinnerDateModel 的日历字段设置为 Calendar.WEEK_OF_MONTH 而不是 Calendar.DAY_OF_WEEK。

当使用 Spinner 按钮时，这个问题得到了无声更正，因为 Spinner 会在提交更改之前设置日历字段（这在 SpinnerDateModel 文档中提到）。不过，您的 @PostConstruct 方法在这有机会发生之前运行。

如果我可以添加另一个建议：您计算星期几的方法非常复杂且非常脆弱（例如在德国它会崩溃，因为 "Sunday" 是 "Sonntag"这里）。这是一个替代方案。在构造函数中用 initial == true 调用它，在 stateChanged() 中用 initial == false 调用它。

private Calendar cal = new GregorianCalendar();

private void skipWeekends(boolean initial) {
    cal.setTime(spinnerModel.getDate());

    switch (cal.get(Calendar.DAY_OF_WEEK)) {
    case Calendar.SATURDAY:
        cal.add(Calendar.DAY_OF_WEEK, initial ? -1 : 2);
        break;
    case Calendar.SUNDAY:
        cal.add(Calendar.DAY_OF_WEEK, -2);
        break;
    }
    spinnerModel.setValue(cal.getTime());
}

Answer 2

我认为您需要 select 当前日历字段，然后它将受到 JSpinner 的 getNextValue() 和 getPreviousValue() 方法的影响。

要制造select离子，您可以使用：

spinner.setCalendarField(Calendar.DAY_OF_YEAR);

JSpinner 跳跃数周而不是数天

JSpinner jumping weeks rather than days

java

swing

date

jspinner