this program is 2 classes and it has 2 JLabels, 2 JTextFileds, and 2 JButtons...
it convert temperatures from Fahrenheit to Celsius and from Celsius to Fahrenheit..
Class 1:
// Author: Helen Toma
import java.awt.BorderLayout;
import java.awt.FlowLayout;
import java.awt.GridLayout;
import javax.swing.JTextField;
import javax.swing.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
public class ConvertTemp extends JFrame {
// instance variables
JLabel labelFahr;
JLabel labelCels;
JTextField textFahr;
JTextField textCels;
JButton conFahToCel;
JButton conCelToFah;
public ConvertTemp () {
super ("Temerature");
setLayout (new FlowLayout ());
labelFahr = new JLabel ("Fahrenheit: ", SwingConstants.LEFT);
labelFahr.setToolTipText("This is a temerature scale");
add (labelFahr);
textFahr = new JTextField (10);
add (textFahr);
labelCels = new JLabel ("Celsius: ", SwingConstants.LEFT);
labelCels.setToolTipText("This is a scale and unit of measurement for temperature");
add (labelCels);
textCels = new JTextField (10);
add (textCels);
conFahToCel = new JButton ("Convert Fahrenheit to Celsius");
add (conFahToCel);
conCelToFah = new JButton ("Convert Celsius to Fahrenheit");
add (conCelToFah);
JPanel panel = new JPanel(new GridLayout(2, 2, 12, 6));
panel.add(labelFahr);
panel.add(labelCels);
panel.add(textFahr);
panel.add(textCels);
add(panel, BorderLayout.NORTH);
JPanel buttonPanel = new JPanel();
buttonPanel.add(conFahToCel);
buttonPanel.add(conCelToFah);
add(buttonPanel, BorderLayout.SOUTH);
conFahToCel.addActionListener(new FahrListener ());
conCelToFah.addActionListener(new CelsListener ());
} // end constructor
private class FahrListener implements ActionListener {
public void actionPerformed(ActionEvent event) {
if (event.getSource() == conFahToCel){
int conFahToCel = (int) ((5.0/9.0 * (((Double.parseDouble(textFahr.getText())) -32))));
textCels.setText(conFahToCel + " °C");
textFahr.requestFocus();
textFahr.selectAll();
} // end if statement
} // end actionPerformed
} // end FahrListener
private class CelsListener implements ActionListener {
public void actionPerformed(ActionEvent event) {
if (event.getSource() == conCelToFah){
int conCelToFah = (int) (( 9.0/5.0 * (((Double.parseDouble(textCels.getText())) + 32))));
textFahr.setText(conCelToFah + " °F");
textCels.requestFocus();
textCels.selectAll();
} // end if statement
} // end actionPerformed
} // end CelsListener
} // end class ConvertTemp---------------------------------------------------------------------------------------
Class 2:
// Author: Helen Toma
import javax.swing.JFrame;
public class ConvertTempTest {
public static void main(String[] args) {
ConvertTemp app = new ConvertTemp ();
app.setDefaultCloseOperation (JFrame.EXIT_ON_CLOSE);
app.setSize (500, 150); // set the frame size
app.setVisible (true); // display frame
} // end main method
} // end class ConvertTempTest
