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

public class AWT_Math {
    public static void main(String[] args){
      new TFrame().launchFrame();
    }
}

class TFrame extends Frame {
  TextField num1,num2,num3;
  public void launchFrame(){
    TextField num1 = new TextField(10);
    TextField num2 = new TextField(10);
    TextField num3 = new TextField(15);
    Label LaPlus = new Label("+");
    Button buqual = new Button("=");
    buqual.addActionListener(new MyMonitor(this));
    setLayout(new FlowLayout());
    add(num1);
    add(LaPlus);
    add(num2);
    add(buqual);
    add(num3);
    pack();
    setVisible(true);
  }
}

class MyMonitor implements ActionListener{


    TFFrame tf = null;
    public  MyMonitor(TFFrame tf){
      this.tf = tf;
    }
    
  public void actionPerformed(ActionEvent e){
    int n1 = Integer.parseInt(tf.num1.getText());
    int n2 = Integer.parseInt(tf.num2.getText());
    tf.num3.setText(""+(n1+n2));
  }
}

public class AWT_Math {
    public static void main(String[] args) {
        new TFrame().launchFrame();
    }
}

class TFrame extends Frame {
    TextField num1, num2, num3;

    public void public class AWT_Math {
    public static void main(String[] args) {
        new TFrame().launchFrame();
    }
}

class TFrame extends Frame {
    TextField num1, num2, num3;

    public void launchFrame() {
        num1 = new TextField(10);
        num2 = new TextField(10);
        num3 = new TextField(15);
        Label LaPlus = new Label("+");
        Button buqual = new Button("=");
        buqual.addActionListener(new MyMonitor(this));
        setLayout(new FlowLayout());
        add(num1);
        add(LaPlus);
        add(num2);
        add(buqual);
        add(num3);
        pack();
        setVisible(true);
    }
}

class MyMonitor implements ActionListener {

    TFrame tf = null;

    public MyMonitor(TFrame tf) {
        this.tf = tf;
    }

    public void actionPerformed(ActionEvent e) {
        int n1 = Integer.parseInt(tf.num1.getText());
        int n2 = Integer.parseInt(tf.num2.getText());
        tf.num3.setText("" + (n1 + n2));
    }
} {
        num1 = new TextField(10);
        num2 = new TextField(10);
        num3 = new TextField(15);
        Label LaPlus = new Label("+");
        Button buqual = new Button("=");
        buqual.addActionListener(new MyMonitor(this));
        setLayout(new FlowLayout());
        add(num1);
        add(LaPlus);
        add(num2);
        add(buqual);
        add(num3);
        pack();
        setVisible(true);
    }
}

class MyMonitor implements ActionListener {

    TFrame tf = null;

    public MyMonitor(TFrame tf) {
        this.tf = tf;
    }

    public void actionPerformed(ActionEvent e) {
        int n1 = Integer.parseInt(tf.num1.getText());
        int n2 = Integer.parseInt(tf.num2.getText());
        tf.num3.setText("" + (n1 + n2));
    }
}

------解决方案--------------------
路过，呵呵上面正解，顶一下

------解决方案--------------------
import java.awt.Button;
import java.awt.FlowLayout;
import java.awt.Frame;
import java.awt.Label;
import java.awt.TextField;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class AWT_Math {
   public static void main(String[] args){
     new TFrame().launchFrame();
   }
}

class TFrame extends Frame {
  TextField num1,num2,num3;
 public void launchFrame(){