Thread: NEED HELP WITH TEMPERATURE

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.applet.*;
 
public class Temperature2 extends JApplet implements ActionListener
{
     private JTextField fahrenheitField, celsiusField;
     private JLabel messageLabel;
     private JButton fahrButton, celsButton, resetButton;
     private double Celsius;
     private double Fahrenheit;
 
 
     public void init()
     {
        Container contentPane = getContentPane();
        JLabel fahrenheitLabel, celsiusLabel, instructionsLabel;
        JPanel fahrenheitPanel, celsiusPanel, resetPanel;
 
 
        fahrenheitPanel = new JPanel();
        celsiusPanel = new JPanel();
        resetPanel= new JPanel();
 
        instructionsLabel = new JLabel("            Temperature Converter Chart");
 
        fahrButton = new JButton("convert to fahrenheit");
		fahrButton.addActionListener(this);
        fahrenheitPanel.add(fahrButton);
 
		celsButton = new JButton("convert to celsius");
		celsButton.addActionListener(this);
        celsiusPanel.add(celsButton);
 
        resetButton = new JButton("Reset");
        resetButton.addActionListener(this);
        resetPanel.add(resetButton);
 
 
        fahrenheitLabel = new JLabel("Temperature in F:");
	    fahrenheitField = new JTextField(9);
	    fahrenheitPanel.add(fahrenheitLabel);
	    fahrenheitPanel.add(fahrenheitField);
 
	    celsiusLabel = new JLabel("Temperature in C:");
	    celsiusField = new JTextField(9);
	    celsiusPanel.add(celsiusLabel);
	    celsiusPanel.add(celsiusField);
 
 
	    contentPane.setLayout(new GridLayout(6, 1));
	    contentPane.add(instructionsLabel);
	    contentPane.add(fahrenheitPanel);
	    contentPane.add(celsiusPanel);
	    contentPane.add(fahrButton);
	    contentPane.add(celsButton);
	    contentPane.add(resetButton);
 
     }
 
	 public void actionPerformed(ActionEvent e)
	 {
 
		if (e.getActionCommand().equals("convert to celsius"))
		{
 
            Celsius = 0;
            Fahrenheit = 0;
		    Celsius = ((5.0 / 9.0) *  (Fahrenheit - 30));
 
 
		 //   double Celsius = Double.parseDouble(celsiusField.getText());
 
            celsiusField.setText(Double.toString(Celsius));
            System.out.println("Temperature in Celcius is:" + Celsius);
 
		}
 
	else if (e.getActionCommand().equals("Reset"))
		{
		    Celsius = 0;
		    Fahrenheit = 0;
		    celsiusField.setText("0.0");
		    fahrenheitField.setText("0.0");
 
		}
 
		else if (e.getActionCommand().equals("convert to fahrenheit"))
		{
 
			Celsius = 0;
			Fahrenheit = 0;
			Fahrenheit = (Celsius * (9.0 / 5.0) + 32);
/**
			double Celsius = Double.parseDouble(fahrenheitField.getText());
*/
            fahrenheitField.setText(Double.toString(Fahrenheit));
            System.out.println("Temperature in Fahrenheit is:" + Fahrenheit);
        }
        else
           celsiusField.setText("Error in convertor code.");
 
      }
 
 
}

In the future please don't ask your same question in multiple categories. I've removed your other topic. What specifically are you having problems with?

If you're getting an error message, please post it in full.

Take a look at your actionPerformed method.

When the user presses the convert to fahrenheit or convert to celsius buttons, you're initializing the values to 0 rather than to the values in the other textbox.

0F = -16.666C and 0C = 32F.

Change these to parse the text from textbox into a number, then convert that number to the other temperature scale.

do you mean like this..

public void actionPerformed(ActionEvent e)
{
  if (e.getActionCommand().equals("convert to celsius"))
 {
 
           [COLOR="Red"] 0Celsius = 32Fahrenheit;
            0Fahrenheit = -16.666Celsius;
            Celsius = ((5.0 / 9.0) *  (Fahrenheit - 30));[/COLOR]
 
          //  [COLOR="Red"]0Celsius = Double.parseDouble(celsiusField.getText());[/COLOR]
 
            celsiusField.setText(Double.toString(Celsius));
            System.out.println("Temperature in Celcius is:" + Celsius);
 
		}

i'm clueless

No, I was simply showing you where you were getting those numbers from. That's not valid Java code

  if (e.getActionCommand().equals("convert to celsius"))
{
            Fahrenheit = Double.parseDouble(fahrenheit.getText());
            Celsius = ((5.0 / 9.0) *  (Fahrenheit - 30));
 
            celsiusField.setText(Double.toString(Celsius));
            //System.out.println("Temperature in Celcius is:" + Celsius); this isn't useful in a GUI app
 
		}

Your handler for converting Celsius to Fahrenheit will be similar to this, but you'll need to change the code around to convert celsius to fahrenheit, rather than convert fahrenheit to celsius.