class1.java

矩阵乘法的计算程序

import java.awt.*;
import java.awt.event.*;
class Handler implements ItemListener{
	public void itemStateChanged(ItemEvent ev){
		String state="deselected";
		if (ev.getStateChange()==ItemEvent.SELECTED)
			state="selected";
		System.out.println(ev.getItem()+" "+state+" on "+ev.getItem());
	}
}
public class Class1
{
	public static void main (String[] args)
	{
		Frame f=new Frame();
		CheckboxGroup cbg=new CheckboxGroup();
		Checkbox ck1=new Checkbox("one",cbg,true); 
		Checkbox ck2=new Checkbox("two",null,false);
		Checkbox ck3=new Checkbox("three",cbg,false);
		Handler handler=new Handler(); 
		f.setLayout(new GridLayout(3,1));
		f.add(ck1);
		f.add(ck2);
		f.add(ck3);
		ck1.addItemListener(handler); 
		ck2.addItemListener(handler);
		f.setSize(100,100);
		f.show();

	
	}
}