// Temperature conversion program based on 5C, page 247 in Mercer Text
// By Dan Hyde, March 7, 2006

import javax.swing.*;           // need for graphics
import java.awt.*;              // need for graphics
import java.awt.event.*;        // need for listeners
import java.text.DecimalFormat; // need for DecimalFormat class

public class TempConversion2 extends JFrame { 

    //instance variables
    JLabel fahrLabel;
    JTextField fahrTextField;
    JLabel celLabel;
    JTextField celTextField;

    // create a DecimalFormat object for printing double values
    DecimalFormat onePlace = new DecimalFormat("0.0");

    // constructor
    public TempConversion2() {

       // Set the title on the title bar
       setTitle("Temp Converter");

       // Set location of upper left corner of window
       setLocation(400, 400);

       // Set size of window to be 150 pixels wide by 80 pixels high
       setSize(200, 80);

       // When user closes window, the program terminates
       setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

       // Create a container associated with the window 
       //        to hold graphical components
       Container contentPane = getContentPane();
	
       // Set the Layout to GridLayout with 2 rows and 2 columns. 
       // 4 pixels separate the horizontal and vertical parts
       GridLayout grid2By2 = new GridLayout(2, 2, 4, 4);
	
       // set Layout of container to be grid2By2.
       contentPane.setLayout(grid2By2);

       // Initialize graphical components: JLabel and JTextField
       celLabel = new JLabel("Celcius:", SwingConstants.RIGHT);
       celTextField = new JTextField("");
       fahrLabel = new JLabel("Fahrenheit:", SwingConstants.RIGHT);
       fahrTextField = new JTextField("");

       // Add graphical components to container
       //     in the order for the Layout
       contentPane.add(celLabel);
       contentPane.add(celTextField);
       contentPane.add(fahrLabel);
       contentPane.add(fahrTextField);

       // Create and register listeners on the two JTextFields
       MyListener1 listenerCelText = new MyListener1();
       celTextField.addActionListener(listenerCelText);

       MyListener2 listenerFahrText = new MyListener2();
       fahrTextField.addActionListener(listenerFahrText);
    }

    /// inner class
    private class MyListener1 implements ActionListener {

	public MyListener1() {
	}

	public void actionPerformed(ActionEvent e1) {
	    double cel;
	    String fahrString;
	    cel = Double.parseDouble(celTextField.getText());
	    
	    fahrString = "" + onePlace.format((cel * 9.0 /5.0 + 32.0));
	    fahrTextField.setText(fahrString);
	}
    }
    /// end of inner class

    /// inner class
    private class MyListener2 implements ActionListener {

	public MyListener2() {
	}

	public void actionPerformed(ActionEvent e1) {
	    double fahr;
	    String celString;
	    fahr = Double.parseDouble(fahrTextField.getText());

	    celString = "" + onePlace.format((5.0 / 9.0 * (fahr - 32.0)));
	    celTextField.setText(celString);
	}
    }
    /// end of inner class

   public static void main(String[] args) {

       // Create a window as JFrame object
       TempConversion2 theWindow = new TempConversion2();

       // Make the window visible to the user
       theWindow.setVisible(true);
    }
}