class1.java

矩阵乘法的计算程序

import java.awt.*;
import java.awt.event.*;
//菜单无法进行布局管理,只能出现在窗口的固定位置
public class Class1
{
	public static void main (String[] args)
	{
		Frame f=new Frame("菜单条");
		Button b=new Button("Press me");
		PopupMenu p=new PopupMenu("Popup");//相当于一个Menu
		MenuItem mi1=new MenuItem("打开文件");
		CheckboxMenuItem mi2=new CheckboxMenuItem("CheckItem");
		p.add(mi1);
		p.add(mi2);
		Handler handler=new Handler();
		handler.p=p;
		handler.b=b;
		b.addActionListener(handler);
		f.add(b);
		f.add(p);//PopupMenu必须在Frame上添加
		f.setSize(180,180);
		f.show();
	
	}
}
class Handler implements ActionListener {
	PopupMenu p;
	Button b;
	public void actionPerformed(ActionEvent e){
		p.show(b,10,10);
	}
}