import java.awt.*;
import java.awt.event.*;


public class AwtExemplo5 extends Frame
    {
    private Button bOk;
    private Button bCancelar;
    private TextField t1, t2, m;
    private Label l1, l2, l3;
    private Panel p1, p2, p3;

    AwtExemplo5(String tit)
        {
        super(tit);

        p1 = new Panel();
        p2 = new Panel();
        p3 = new Panel();

        l1 = new Label("Nota 1: ");
        l2 = new Label("Nota 2: ");
        l3 = new Label("Media: ");

        bOk = new Button("OK");
        bOk.addActionListener(new BOk());

        bCancelar = new Button("Cancelar");
        bCancelar.addActionListener(new BCancelar());

        t1 = new TextField(20);
        t2 = new TextField(20);
        m  = new TextField(20);
        setLayout(new FlowLayout());
        p1.setLayout(new GridLayout(3,1,5,5));
        p1.add(l1);
        p1.add(l2);
        p1.add(l3);
        p2.setLayout(new GridLayout(3,1,5,5));
        p2.add(t1);
        p2.add(t2);
        p2.add(m);
        p3.setLayout(new GridLayout(1,2,5,5));
        p3.add(bOk);
        p3.add(bCancelar);
        add("West", p1);
        add("Center",p2);
        add("South",p3);
        }

    class BOk implements ActionListener
        {
        public void actionPerformed(ActionEvent e)
            {
            float med;
            med= (Float.parseFloat(t1.getText()) + Float.parseFloat(t2.getText()))/2;
            m.setText(String.valueOf(med));
            }
        }

    class BCancelar implements ActionListener
        {
        public void actionPerformed(ActionEvent e)
            {
            t1.setText("");
            t2.setText("");
            m.setText("");
            }
        }

    static class WL extends WindowAdapter
        {
        public void windowClosing(WindowEvent e)
            {
            System.exit(0);
            }
        }

    public static void main(String args[])
        {
        AwtExemplo5 app = new AwtExemplo5("Meu AwtExemplo4");

        app.addWindowListener(new WL());

        app.setSize(300,300);
        app.show();
        }
    }