java实现计算器加法小程序（图形化界面）

package 实例11;
import java.awt.*;
import java.awt.event.*;
 
public class Test {
 public static void main(String[]args){
 new MyFrame().launchMyFrame();
 }
 
 
}
 
class MyFrame extends Frame{
 public void launchMyFrame(){
 TextField tf1 = new TextField();
 TextField tf2 = new TextField();
 TextField tf3 = new TextField();
 Label l = new Label("+");
 Button b = new Button("=");
 Monitor m = new Monitor(tf1, tf2, tf3); //通过构造方法将三个局部变量传递Monitor
 b.addActionListener(m);
 setLayout(new FlowLayout());
 add(tf1);
 add(l);
 add(tf2);
 add(b);
 add(tf3);
 pack();
 setVisible(true);
 }
}
 
class Monitor implements ActionListener{
 TextField tf1, tf2, tf3;
 public Monitor(TextField tf1, TextField tf2, TextField tf3){
 this.tf1 = tf1;
 this.tf2 = tf2;
 this.tf3 = tf3;
 }
 public void actionPerformed(ActionEvent e){
 int a = Integer.parseInt(tf1.getText());
 int b = Integer.parseInt(tf2.getText());
 int c = a + b;
 tf3.setText(""+c);
 System.out.println(c);
 }
}

package 实例11;
import java.awt.*;
import java.awt.event.*;
 
public class Test {
 public static void main(String[]args){
 new MyFrame().launchMyFrame();
 }
 
 
}
 
class MyFrame extends Frame{
 TextField tf1, tf2, tf3;
 public void launchMyFrame(){
 tf1 = new TextField();
 tf2 = new TextField();
 Label l = new Label("+");
 Button b = new Button("=");
 Monitor m = new Monitor(this);
 b.addActionListener(m);
 setLayout(new FlowLayout());
 add(tf1);
 add(l);
 add(tf2);
 add(b);
 add(tf3);
 pack();
 setVisible(true);
 }
}
 
class Monitor implements ActionListener{
 MyFrame mf = null;
 public Monitor(MyFrame mf){
 this.mf = mf;
 }
 public void actionPerformed(ActionEvent e){
 int a = Integer.parseInt(mf.tf1.getText());
 int b = Integer.parseInt(mf.tf2.getText());
 int c = a + b;
 mf.tf3.setText(""+c);
 System.out.println(c);
 }
}