GUI month names

Chapter: GUI month names

Create a new class in your project named GUIMonthNames, with superclass javax.swing.JFrame, and with a method stub for public static void main(String[] args). As in the last lab write a constructor that does all the usual housekeeping:

public GUIMonthNames() {
  super("Month Names: GUI version");
  setSize(400,400);
  setDefaultCloseOperation(EXIT_ON_CLOSE);
  setVisible(true);
  Container myPane = getContentPane();
  myPane.setLayout(new FlowLayout());
}

Be sure to import the usual classes:

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

Also be sure to call the constructor by adding new GUIMonthNames(); to the main() method. Now let's tell the user story:

The user is faced with a message requesting "Enter a number (1 - 12) below".
The user should enter a number in a text field
When the user hits the Enter key the month number is replaced by the month name

I want you to use a JLabel (see the documentation) to provide the user instructions. I want you to use a JTextField to input the number and output the results. Accordingly, you declare:

	private JLabel instructions;
	private JTextField data;

and add these lines to the constructor:

		instructions = new JLabel("Enter a number (1-12) below");
		data = new JTextField(20);

To see the meaning of the 20 as an argument to the JTextField constructor you should consult the API documentation.

At this point you should compile and run your program. You should see a JFrame, something like this:

Of course nothing works yet!

Exercise 2

Make your GUI program work by adding an action listener to the JTextField.

		data.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent e) {
				int monthNumber = new Integer(data.getText());
        // add your code here
			}
		});

You will need to add the code from the main method of your non-GUI program from the previous exercise. Mostly it will be unchanged, but there will be some small modifications:

You still need the constant MONTH_TABLE just as before
You still need the int start and int stop just as before
You still need to compute the String monthName just as before
Instead of printing to System.out you will simply set the text of the JTextField data using data.setText(...)
You also won't need the linefeed in the output text

That's it: Just enter the code into the body of the actionPerformed method.

rhyspj@gwu.edu