import java.applet.Applet;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextArea;
import javax.swing.JTextField;
class Sample extends Applet
{
public static void main(String[] args)
{
JFrame frame=new JFrame("Sample");
JPanel panel=new JPanel();
JPanel panel1=new JPanel();
JPanel panel2=new JPanel();
JPanel panel3=new JPanel();
final JLabel la1 = new JLabel("数学:");
final JLabel la2 = new JLabel("语文:");
final JLabel la3 = new JLabel("英语:");
final JTextArea tf =new JTextArea(1, 15);
tf.setEditable(false);
final JTextField ta = new JTextField(15);
final JTextField tb = new JTextField(15);
final JTextField tc = new JTextField(15);
JButton button=new JButton("平均分");
panel.add(la1);
panel.add(ta);
panel1.add(la2);
panel1.add(tb);
panel2.add(la3);
panel2.add(tc);
panel3.add(button);
panel3.add(tf);
Sample app=new Sample();
frame.add(app);
button.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
double a = Double.parseDouble(ta.getText());
double b = Double.parseDouble(tb.getText());
double c = Double.parseDouble(tc.getText());
tf.setText(String.valueOf((a + b + c)/3));
}
});
app.setLayout(new FlowLayout());
app.add(panel);
app.add(panel1);
app.add(panel2);
app.add(panel3);
frame.setSize(400,400);
frame.setVisible(true);
app.init();
app.start();
}
public void destroy()
{
System.exit(0);
}
}