显示时间在组合框中(show the time in a combobox)

我想实现一个组合框，显示了一天的每一个小时的名单，但没有成功。它给了我“构造的JComboBox（JSpinner的）是未定义”的错误。任何帮助吗？谢谢

    Calendar calendar = Calendar.getInstance();
    calendar.set(Calendar.HOUR_OF_DAY, 24);
    calendar.set(Calendar.MINUTE, 0);
    SpinnerDateModel model = new SpinnerDateModel();
    model.setValue(calendar.getTime());
    JSpinner spinner = new JSpinner(model);
    departureTime = new JComboBox<String>(spinner);

Answer 1:

不，这是没有意义的。你应该通过一个组合框ComboBoxModel填充想要显示的值

请参阅如何使用组合框和如何使用纱厂了解更多详情

您可以使用像这样它使用JSpinner来显示时间，并允许用户对其进行操作

或者你需要在你希望用户被允许选择，诸如给定的时间间隔的数值，以填补组合框...

import java.awt.Component;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.GridBagLayout;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import javax.swing.DefaultComboBoxModel;
import javax.swing.DefaultListCellRenderer;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;

public class Test {

    public static void main(String[] args) {
        new Test();
    }

    public Test() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
                    ex.printStackTrace();
                }

                JFrame frame = new JFrame("Testing");
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.add(new TestPane());
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
            }
        });
    }

    public class TestPane extends JPanel {

        public TestPane() {
            setLayout(new GridBagLayout());
            Calendar calendar = Calendar.getInstance();
            calendar.set(Calendar.HOUR_OF_DAY, 0);
            calendar.set(Calendar.MINUTE, 0);

            Calendar end = Calendar.getInstance();
            end.set(Calendar.HOUR_OF_DAY, 23);
            end.set(Calendar.MINUTE, 59);
            DefaultComboBoxModel<Date> model = new DefaultComboBoxModel<>();
            do {
                model.addElement(calendar.getTime());
                calendar.add(Calendar.MINUTE, 15);
            } while (calendar.getTime().before(end.getTime()));

            JComboBox<Date> cb = new JComboBox<>(model);
            cb.setRenderer(new DateFormattedListCellRenderer(new SimpleDateFormat("HH:mm")));

            add(cb);

        }

        @Override
        public Dimension getPreferredSize() {
            return new Dimension(200, 200);
        }

        public class DateFormattedListCellRenderer extends DefaultListCellRenderer {

            private DateFormat format;

            public DateFormattedListCellRenderer(DateFormat format) {
                this.format = format;
            }

            @Override
            public Component getListCellRendererComponent(JList<?> list, Object value, int index, boolean isSelected, boolean cellHasFocus) {
                if (value instanceof Date) {
                    value = format.format((Date) value);
                }
                return super.getListCellRendererComponent(list, value, index, isSelected, cellHasFocus);
            }

        }

    }

}

Answer 2:

我不知道什么ü想与日历做，但每天有24个小时，添加列表在24小时或者创建拥有MAXVALUE 24的好手。