Date and Time entry

[Layne Lund]

Does Swing or AWT have a component for entering a date? I'm picturing a button that the user clicks that causes a calendar to popup. Then the user can choose the date.

Also is there something similar for time? Perhaps a JFormattedTextField will be sufficient for my needs here, but a "calendar picker" of some sort would be much more convenient for the date.

Thanks in advance.

Layne

[Michael Dunn]

Here's something to play around with.
It's a bit rough - old code, I should clean it up (maybe one day)

import java.util.*;
import java.text.*;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
class MainApp extends JFrame
{
  JLabel lbl = new JLabel(" ");
  JFrame main = this;
  public MainApp()
  {
    super("Main Application");
    setSize(400,100);
    setLocation(250,200);
    setDefaultCloseOperation(EXIT_ON_CLOSE);
    JPanel jp = new JPanel(new BorderLayout());
    JButton btn = new JButton("Pick-A-Date");
    btn.addActionListener(new ActionListener(){
      public void actionPerformed(ActionEvent e){
          pickDate();}});
    jp.add(lbl,BorderLayout.NORTH);
    jp.add(btn,BorderLayout.SOUTH);
    getContentPane().add(jp);
  }
  public void pickDate()
  {
    class DatePicker extends JDialog implements ActionListener
    {
      JButton btns[] = new JButton[49];
      JButton btnNext = new JButton("Forward 1 Month >>>");
      JButton btnLast = new JButton("<<< Back 1 Month");
      JLabel lblMth = new JLabel();
      JLabel lblYr = new JLabel();
      Calendar cal = Calendar.getInstance();
      String months[] = {"January","February","March","April",
      "May","June","July","August","September","October","November","December"};
      int mth = 0;
      int yr = 0;
      SimpleDateFormat sdf = new SimpleDateFormat("EEEE, dd MMMM yyyy");
 
      public DatePicker()
      {
        setTitle("Date Picker");
        setModal(true);
        setDefaultCloseOperation(DISPOSE_ON_CLOSE);
        getContentPane().setLayout(new BorderLayout());
        mth = cal.get(cal.MONTH);
        yr = cal.get(cal.YEAR);
        JPanel top = new JPanel(new FlowLayout());
        top.add(lblMth);
        top.add(lblYr);
        JPanel mid = new JPanel(new GridLayout(7,7));
        String days[] = {"S","M","Tu","W","Th","F","S"};
        for(int i = 0; i < btns.length; i++)
        {
          btns[i] = new JButton();
          btns[i].setFont(new Font("Arial",Font.BOLD, 12));
          btns[i].setPreferredSize(new Dimension(50,50));
          if(i < 7)btns[i].setText(days[i]);
          else
          {
            btns[i].addActionListener(this);
            btns[i].setFont(new Font("Arial",Font.BOLD, 12));
          }
          mid.add(btns[i]);
        }
        btnNext.addActionListener(this);
        btnLast.addActionListener(this);
        JPanel bottom = new JPanel(new FlowLayout());
        bottom.add(btnLast);
        bottom.add(btnNext);
        getContentPane().add(top,BorderLayout.NORTH);
        getContentPane().add(mid,BorderLayout.CENTER);
        getContentPane().add(bottom,BorderLayout.SOUTH);
        setDates();
        setLocation(300,200);
        pack();
        setVisible(true);
      }
      private void setDates()
      {
        for(int i = 7; i < btns.length; i++) btns[i].setText("");
        cal.set(yr,mth,1);
        lblMth.setText(months[cal.get(cal.MONTH)]);
        lblYr.setText(String.valueOf(cal.get(cal.YEAR)));
        int firstDay = cal.get(cal.DAY_OF_WEEK)-1+7;
        int ii = 1;
        for(int i = firstDay; i<firstDay+31; i++)
        {
          btns[i].setText(String.valueOf(ii));
          ii++;
          cal.add(cal.DATE,1);
          if(cal.get(cal.MONTH) != (1200 + mth)%12) break;
        }
      }
      public void actionPerformed(ActionEvent ae)
      {
        if(ae.getSource() == btnLast)
        {
          mth--;
          setDates();
        }
        else if(ae.getSource() == btnNext)
        {
          mth++;
          setDates();
        }
        else
        {
          for(int i = 7; i < btns.length; i++)
          {
            if(ae.getSource() == btns[i])
            {
              if(!btns[i].getText().equals(""))
              {
                Calendar cal2 = Calendar.getInstance();
                cal2.set(yr,mth,Integer.parseInt(btns[i].getText()));
                lbl.setText("You selected - " + sdf.format(cal2.getTime()));
                main.setVisible(true);
                dispose();
              }
              break;
            }
          }
        }
      }
    }
    setVisible(false);
    new DatePicker();
  }
  public static void main(String args[]) {new MainApp().setVisible(true);}
}

[Layne Lund]

Thanks. I'll take a look at this code to see if it helps. I'm still wondering if Swing (or any other standard Java API) provides this functionality?

[Dr Black]

There is a free calender program with a popup month calander that you can pick the date and it puts it in the date text field. Do a Google on 'java calendar examples'. If you use a database I have found that always storing the date as 'timestamp' solves lots of problems. Move the date around using java,util,Date keeps things neet and orderly. If you store the date as timestamp the same data can be shown on the screen as a date in one field and time in a different field using the Java 'simple.date.format' classes on the same timestamp field.

timestamp is ALWAYS stored as YYYMMDDhhmmssss even though you may specific fewer characters to the database.

[Layne Lund]

Thanks for your comments. Unfortunately (or perhaps fortunately), this program will deal with flat files for persistant storage.

Layne