java例程练习（简单的计算器[调停者设计模式及内部类]）(一)

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

public class TestInnerClass {

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

}

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

}

class MyMonitor implements ActionListener {
TextField num1,num2,num3;
MyMonitor(TextField num1, TextField num2, TextField num3) {//用构造函数实现
this.num1 = num1;
this.num2 = num2;
this.num3 = num3;
}


public void actionPerformed(ActionEvent e) {
int n1 = Integer.parseInt(num1.getText());
int n2 = Integer.parseInt(num2.getText());
int n3 = n1 + n2;
num3.setText("" + n3);

}
}
[java]
import java.awt.*;
import java.awt.event.*;

public class TestInnerClass {

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

}

class TFFrame extends Frame {
public void launchFrame() {
TextField num1 = new TextField(10);
TextField num2 = new TextField(10);
TextField num3 = new TextField(15);
Label lbPlus = new Label("+");
Button btnEqual = new Button("=");
setLayout(new FlowLayout());
add(num1);