使用Java Swing的日历显示

Question

I am working on an attendance project in java swing (a stand alone application), which updates attendance of each employee whenever they log in with their user id and password.

Attendance will be taken only once in a day.

Now, I want to display a calendar with the days he logged in marked a different color from the days he didn't (meaning he was absent those un-logged-in days).

My current status is in the link http://devajkumarsuthapalli.blogspot.in/2013/06/my-java-project_20.html in a calendar like this http://tinyurl.com/ps23csu

I want to see employees logged in days with different color and absentees with a different color

Answer 1

You're going to have to create your own Calendar component so that you can set the days to different colors.

Here's a calendar I created for one of my projects.

Here's the MonthPanel code that produces the calendar. Right now, it highlights the current day. You can modify it to highlight the days that your employees log in.

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.GridLayout;
import java.awt.SystemColor;
import java.util.Calendar;

import javax.swing.BorderFactory;
import javax.swing.JLabel;
import javax.swing.JPanel;

public class MonthPanel extends JPanel {

    private static final long   serialVersionUID    = 1L;

    protected int               month;
    protected int               year;

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

    protected String[]          dayNames            = { "S", "M", "T", "W",
            "T", "F", "S"                           };

    public MonthPanel(int month, int year) {
        this.month = month;
        this.year = year;

        this.add(createGUI());
    }

    protected JPanel createGUI() {
        JPanel monthPanel = new JPanel(true);
        monthPanel.setBorder(BorderFactory
                .createLineBorder(SystemColor.activeCaption));
        monthPanel.setLayout(new BorderLayout());
        monthPanel.setBackground(Color.WHITE);
        monthPanel.setForeground(Color.BLACK);
        monthPanel.add(createTitleGUI(), BorderLayout.NORTH);
        monthPanel.add(createDaysGUI(), BorderLayout.SOUTH);

        return monthPanel;
    }

    protected JPanel createTitleGUI() {
        JPanel titlePanel = new JPanel(true);
        titlePanel.setBorder(BorderFactory
                .createLineBorder(SystemColor.activeCaption));
        titlePanel.setLayout(new FlowLayout());
        titlePanel.setBackground(Color.WHITE);

        JLabel label = new JLabel(monthNames[month] + " " + year);
        label.setForeground(SystemColor.activeCaption);

        titlePanel.add(label, BorderLayout.CENTER);

        return titlePanel;
    }

    protected JPanel createDaysGUI() {
        JPanel dayPanel = new JPanel(true);
        dayPanel.setLayout(new GridLayout(0, dayNames.length));

        Calendar today = Calendar.getInstance();
        int tMonth = today.get(Calendar.MONTH);
        int tYear = today.get(Calendar.YEAR);
        int tDay = today.get(Calendar.DAY_OF_MONTH);

        Calendar calendar = Calendar.getInstance();
        calendar.set(Calendar.MONTH, month);
        calendar.set(Calendar.YEAR, year);
        calendar.set(Calendar.DAY_OF_MONTH, 1);

        Calendar iterator = (Calendar) calendar.clone();
        iterator.add(Calendar.DAY_OF_MONTH,
                -(iterator.get(Calendar.DAY_OF_WEEK) - 1));

        Calendar maximum = (Calendar) calendar.clone();
        maximum.add(Calendar.MONTH, +1);

        for (int i = 0; i < dayNames.length; i++) {
            JPanel dPanel = new JPanel(true);
            dPanel.setBorder(BorderFactory.createLineBorder(Color.BLACK));
            JLabel dLabel = new JLabel(dayNames[i]);
            dPanel.add(dLabel);
            dayPanel.add(dPanel);
        }

        int count = 0;
        int limit = dayNames.length * 6;

        while (iterator.getTimeInMillis() < maximum.getTimeInMillis()) {
            int lMonth = iterator.get(Calendar.MONTH);
            int lYear = iterator.get(Calendar.YEAR);

            JPanel dPanel = new JPanel(true);
            dPanel.setBorder(BorderFactory.createLineBorder(Color.BLACK));
            JLabel dayLabel = new JLabel();

            if ((lMonth == month) && (lYear == year)) {
                int lDay = iterator.get(Calendar.DAY_OF_MONTH);
                dayLabel.setText(Integer.toString(lDay));
                if ((tMonth == month) && (tYear == year) && (tDay == lDay)) {
                    dPanel.setBackground(Color.ORANGE);
                } else {
                    dPanel.setBackground(Color.WHITE);
                }
            } else {
                dayLabel.setText(" ");
                dPanel.setBackground(Color.WHITE);
            }
            dPanel.add(dayLabel);
            dayPanel.add(dPanel);
            iterator.add(Calendar.DAY_OF_YEAR, +1);
            count++;
        }

        for (int i = count; i < limit; i++) {
            JPanel dPanel = new JPanel(true);
            dPanel.setBorder(BorderFactory.createLineBorder(Color.BLACK));
            JLabel dayLabel = new JLabel();
            dayLabel.setText(" ");
            dPanel.setBackground(Color.WHITE);
            dPanel.add(dayLabel);
            dayPanel.add(dPanel);
        }

        return dayPanel;
    }

}

And here's the code I used to produce the JFrame to display the MonthPanel .

import java.awt.FlowLayout;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

import javax.swing.JFrame;
import javax.swing.SwingUtilities;

public class CalendarFrame implements Runnable {

    private JFrame  frame;

    @Override
    public void run() {
        // Month is zero based
        MonthPanel panel = new MonthPanel(5, 2013);

        frame = new JFrame();
        frame.setTitle("Calendar");
        frame.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
        frame.addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent event) {
                exitProcedure();
            }
        });

        frame.setLayout(new FlowLayout());
        frame.add(panel);
        frame.pack();
        // frame.setBounds(100, 100, 400, 200);
        frame.setVisible(true);
    }

    public void exitProcedure() {
        frame.dispose();
        System.exit(0);
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new CalendarFrame());

    }

}

Answer 2

The LGoodDatePicker library includes a CalendarPanel component, which allows the programmer to (optionally) specify a multicolor "HighlightPolicy". By using a HighlightPolicy, the programmer can choose a background color, a foreground color, and (optional) tooltip text for each highlighted date. (The supplied colors can be all the same, or unique per date.) In your usage, the highlight colors could be used to indicate employee attendance.

Fair disclosure: I'm the primary developer.

I pasted a screenshot of a CalendarPanel with a multicolor HighlightPolicy, (and a VetoPolicy).

Besides the CalendarPanel, the library also has the DatePicker, TimePicker, and DateTimePicker components. I included screenshots of all the library components (and the demo application).

The library can be installed into your Java project from the project release page .

The project home page is on Github at:
https://github.com/LGoodDatePicker/LGoodDatePicker .

(Click to zoom the demo image.)