Tue Mar 31, 2009 2:10 pm
import java.awt.BorderLayout;
import java.awt.Container;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;
public class Calculator extends JPanel implements ActionListener
{
private JTextField display = new JTextField("0");
private String button = "789/456*123.=+";
private double result = 0;
private String operator = "=";
private boolean calculating = true;
private boolean decimal = false;
public Calculator()
{
setLayout(new BorderLayout());
display.setEditable(false);
add(display, "North");
JPanel p = new JPanel();
p.setLayout (new GridLayout (4,4));
for (int i = 0; i < button.length(); i++)
{
JButton b = new JButton(button.substring(i, i + 1));
p.add(b);
b.addActionListener(this);
}
add(p, "Center");
}
public void actionPerformed(ActionEvent evt)
{
String cmd = evt.getActionCommand();
if ('0' <= cmd.charAt(0) && cmd.charAt(0) <= '9' || cmd.equals("."))
{
System.out.println("Entered Here");
if (calculating){
System.out.println("Entered calculating "+ cmd.charAt(0));
display.setText(cmd);
}
else
display.setText(display.getText() + cmd);
calculating = false;
}
else
{
if(calculating)
{
if (cmd.equals("-"))
calculating = false;
}
else
{
try{
double x = Double.parseDouble(display.getText());
calculate(x);
operator = cmd;
calculating = true;
}catch(NumberFormatException e){
display.setText("Illegal Number Format");
calculating = false;
}
calculating = true;
}
}
}
private void calculate(double n)
{
if(operator.equals("+"))
result += n;
else if(operator.equals("-"))
result -= n;
else if(operator.equals("/"))
result /= n;
else if(operator.equals("*"))
result *= n;
else if(operator.equals("="))
result = n;
display.setText("" + result);
}
public static void main(String[] args)
{
JFrame frame = new JFrame();
frame.setTitle("Calculator");
frame.setBounds(250,250,200,200);
frame.addWindowListener(new WindowAdapter()
{
public void windowClosing(WindowEvent e)
{
System.exit(0);
}
});
Container contentPane = frame.getContentPane();
contentPane.add(new Calculator());
frame.show();
}
} Codemiles.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com
Powered by phpBB © phpBB Group.