Simple Date Picker application with Java

Most of the time when developing desktop applications, it may need calendar components(or Date Picker in the term :)). This is a very simple Date Picker example to those who are little bit familiar with java swing.

• Go into your favourite java editor and create a file TestDatePicker.java
• Copy following code and paste at there and save it.

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

class DatePicker {
    int month = java.util.Calendar.getInstance().get(java.util.Calendar.MONTH);
    int year = java.util.Calendar.getInstance().get(java.util.Calendar.YEAR);;
    JLabel l = new JLabel("", JLabel.CENTER);
    String day = "";
    JDialog d;
    JButton[] button = new JButton[49];

    public DatePicker(JFrame parent) {
            d = new JDialog();
            d.setModal(true);
            String[] header = { "Sun", "Mon", "Tue", "Wed", "Thur", "Fri", "Sat" };
            JPanel p1 = new JPanel(new GridLayout(7, 7));
            p1.setPreferredSize(new Dimension(430, 120));

            for (int x = 0; x < button.length; x++) {
                    final int selection = x;
                    button[x] = new JButton();
                    button[x].setFocusPainted(false);
                    button[x].setBackground(Color.white);
                    if (x > 6)
                            button[x].addActionListener(new ActionListener() {
                                    public void actionPerformed(ActionEvent ae) {
                                            day = button[selection].getActionCommand();
                                            d.dispose();
                                    }
                            });
                    if (x < 7) {
                            button[x].setText(header[x]);
                            button[x].setForeground(Color.red);
                    }
                    p1.add(button[x]);
            }
            JPanel p2 = new JPanel(new GridLayout(1, 3));
            JButton previous = new JButton("<< Previous");
            previous.addActionListener(new ActionListener() {
                    public void actionPerformed(ActionEvent ae) {
                            month--;
                            displayDate();
                    }
            });
            p2.add(previous);
            p2.add(l);
            JButton next = new JButton("Next >>");
            next.addActionListener(new ActionListener() {
                    public void actionPerformed(ActionEvent ae) {
                            month++;
                            displayDate();
                    }
            });
            p2.add(next);
            d.add(p1, BorderLayout.CENTER);
            d.add(p2, BorderLayout.SOUTH);
            d.pack();
            d.setLocationRelativeTo(parent);
            displayDate();
            d.setVisible(true);
    }

    public void displayDate() {
            for (int x = 7; x < button.length; x++)
                    button[x].setText("");
            java.text.SimpleDateFormat sdf = new java.text.SimpleDateFormat(
                            "MMMM yyyy");
            java.util.Calendar cal = java.util.Calendar.getInstance();
            cal.set(year, month, 1);
            int dayOfWeek = cal.get(java.util.Calendar.DAY_OF_WEEK);
            int daysInMonth = cal.getActualMaximum(java.util.Calendar.DAY_OF_MONTH);
            for (int x = 6 + dayOfWeek, day = 1; day <= daysInMonth; x++, day++)
                    button[x].setText("" + day);
            l.setText(sdf.format(cal.getTime()));
            d.setTitle("Date Picker");
    }

    public String setPickedDate() {
            if (day.equals(""))
                    return day;
            java.text.SimpleDateFormat sdf = new java.text.SimpleDateFormat(
                            "dd-MM-yyyy");
            java.util.Calendar cal = java.util.Calendar.getInstance();
            cal.set(year, month, Integer.parseInt(day));
            return sdf.format(cal.getTime());
    }
}

public class TestDatePicker {
 
 public static void main(String[] args) {  
   /////////////Picker/////////////////////////
  JLabel selectDate = new JLabel("Select Date Here ->");
  JLabel selectedDate= new JLabel("Selected Date ->");
        final JTextField text = new JTextField(20);       
        JButton b = new JButton("Select"); //button for calendar popup
        JButton close = new JButton("Close"); //button for close the application
        JPanel pPic = new JPanel();
        pPic.setLayout(new GridLayout(3,2));
        pPic.add(selectDate);       
        pPic.add(b);
        pPic.add(selectedDate);
        pPic.add(text);
        pPic.add(close);
        final JFrame f = new JFrame("Simple Date Picker");
        f.getContentPane().add(pPic);
        f.pack();
        f.setVisible(true);
        b.addActionListener(new ActionListener() {
                public void actionPerformed(ActionEvent ae) {
                 text.setText(new DatePicker(f).setPickedDate());
                }
        });
        ////////////////////////Picker////////////////////////////
      
        close.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent ae) {
             f.dispose();
            }
        });                
 }  
}

When you run the program, firstly you will see the main frame of the application which looks like,

Then when you hit on 'Select' button, the calendar will be popup as follows

Select what ever the date you like(you can even navigate for other months as well with 'Previous' and 'Next' buttons). The selected date will be included in the text field below the 'Select' button, as follows.

It's done :)

Cheers!!!