a5_8.java

JAVA的课后作业题答案.. 并且附带了调试结果和原码 原理是利用APPLET和事件响应

/*<APPLET  Code="a5_8.class"
   Width=300    Height=300>
 </APPLET>*/

import java.applet.*;
import java.awt.*;
import java.awt.event.*;
public class a5_8 extends Applet implements ActionListener
{
	 int  x =10;
     Button buttonbig = new Button("big");
     Button buttonsmall =new Button("small");
     public void init()
	{
	    setLayout(new FlowLayout());
		add(buttonbig);
		add(buttonsmall);
		buttonsmall.addActionListener(this);
        buttonbig.addActionListener(this);
    }
	public void paint (Graphics g)
	{
      g.setFont(new Font("Dialog",Font.BOLD,x));
      g.drawString("aaaa",100,100);	
	}

 public void actionPerformed (ActionEvent e)
	{
		if(e.getSource()== buttonbig)
		 x+=10;
		else if(e.getSource()== buttonsmall)
        x-=10;
		if (x<10)
		x=10;
		if (x>100)
		x=100;
		repaint();
	}
}