各位前辈,下面的代码怎么改呀,谢谢! Dd这个类既然implemets了 ActionListener 接口本身又不是抽象类肯定要把ActionListener 里面的方法实现了,不然编译通不过加上一个方法吧public voidactionPerformed(java.awt.event.ActionEvent){}就可以了 解决方案 » 免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货 public class Dd extends Applet implements ActionListener 或者把 implements ActionListener 把这段去掉 import java.applet.*; import java.awt.*; import java.awt.event.*; import javax.swing.*; import java.math.*; public class Dd extends Applet implements ActionListener { Label l1,l2; TextField t1; Button b1; String s1; int a,b,c,i; char ch[]={'+','-','*','/'}; public void init() { setLayout(new FlowLayout()); a=(int)(Math.random()*10); b=(int)(Math.random()*10); i=(int)(Math.random()*4); s1=new String(String.valueOf(a)+String.valueOf(ch[i])+String.ValueOf(b)+"="); l1=new Label(s1); l2=new Label(" "); b1=new Button("判断"); t1=new TextField(2); this.add(l1); this.add(t1); this.add(b1); this.add(l2); b1.addActionListener(this); } public void actionPerformed(ActionEvent e) { c=Integer.valueOf(t1.getText()); if(c==a+ch[i]+b) { l2.setText(s1+String.valueOf(c)+"正确!"); } else { l2.setText(s1+String.valueOf(c)+"错误!"); } t1.setText(""); a=(int)(Math.random()*10); b=(int)(Math.random()*10); i=(int)(Math.random()*4); s1=new String(String.valueOf(a)+String.valueOf(ch[i])+String.ValueOf(b)+"="); l1.setText(s1); } public void start() {} public void stop() {} public void destroy() {} public void paint(Graphics g) {} } 还有两处...import java.applet.*; import java.awt.*; import java.awt.event.*; import javax.swing.*; import java.math.*; public class Dd extends Applet implements ActionListener { Label l1,l2; TextField t1; Button b1; String s1; int a,b,c,i; char ch[]={'+','-','*','/'}; public void init() { setLayout(new FlowLayout()); a=(int)(Math.random()*10); b=(int)(Math.random()*10); i=(int)(Math.random()*4); s1=new String(String.valueOf(a)+String.valueOf(ch[i])+String.valueOf(b)+"="); l1=new Label(s1); l2=new Label(" "); b1=new Button("判断"); t1=new TextField(2); this.add(l1); this.add(t1); this.add(b1); this.add(l2); b1.addActionListener(this); } public void actionPerformed(ActionEvent e) { c=Integer.valueOf(t1.getText()); if(c==a+ch[i]+b) { l2.setText(s1+String.valueOf(c)+"正确!"); } else { l2.setText(s1+String.valueOf(c)+"错误!"); } t1.setText(""); a=(int)(Math.random()*10); b=(int)(Math.random()*10); i=(int)(Math.random()*4); s1=new String(String.valueOf(a)+String.valueOf(ch[i])+String.valueOf(b)+"="); l1.setText(s1); } public void start() {} public void stop() {} public void destroy() {} public void paint(Graphics g) {} } request.setAttribute("v1",1); 关于SSH一个小项目的问题 有关于form属性 multipart/form-data取不带action传来的值 高分求助:两个页面有时候无法输入中文,求高手...如何调试?[ JFreeChart 折线图无法显示纵坐标 ajax问题 如何在jsp里写代码转向一个jsp页面而不是重定向? 高手请教~~ ASP.NET与JSP哪个更有前景? 高分奉送!!!谁知道哪里有完整的JSP 新闻发布程序,200分就归您啦!! 一个案例实现问题(急),希望高手解答。 下面代码中为什么要用到ServletContext application?
或者把 implements ActionListener 把这段去掉
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.math.*; public class Dd extends Applet implements ActionListener
{
Label l1,l2;
TextField t1;
Button b1;
String s1;
int a,b,c,i;
char ch[]={'+','-','*','/'};
public void init()
{
setLayout(new FlowLayout());
a=(int)(Math.random()*10);
b=(int)(Math.random()*10);
i=(int)(Math.random()*4);
s1=new String(String.valueOf(a)+String.valueOf(ch[i])+String.ValueOf(b)+"=");
l1=new Label(s1);
l2=new Label(" ");
b1=new Button("判断");
t1=new TextField(2);
this.add(l1);
this.add(t1);
this.add(b1);
this.add(l2);
b1.addActionListener(this);
}
public void actionPerformed(ActionEvent e)
{
c=Integer.valueOf(t1.getText());
if(c==a+ch[i]+b)
{
l2.setText(s1+String.valueOf(c)+"正确!");
}
else
{
l2.setText(s1+String.valueOf(c)+"错误!");
}
t1.setText("");
a=(int)(Math.random()*10);
b=(int)(Math.random()*10);
i=(int)(Math.random()*4);
s1=new String(String.valueOf(a)+String.valueOf(ch[i])+String.ValueOf(b)+"=");
l1.setText(s1);
}
public void start()
{}
public void stop()
{}
public void destroy()
{}
public void paint(Graphics g)
{}
}
import java.applet.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.math.*; public class Dd extends Applet implements ActionListener
{
Label l1,l2;
TextField t1;
Button b1;
String s1;
int a,b,c,i;
char ch[]={'+','-','*','/'};
public void init()
{
setLayout(new FlowLayout());
a=(int)(Math.random()*10);
b=(int)(Math.random()*10);
i=(int)(Math.random()*4);
s1=new String(String.valueOf(a)+String.valueOf(ch[i])+String.valueOf(b)+"=");
l1=new Label(s1);
l2=new Label(" ");
b1=new Button("判断");
t1=new TextField(2);
this.add(l1);
this.add(t1);
this.add(b1);
this.add(l2);
b1.addActionListener(this);
}
public void actionPerformed(ActionEvent e)
{
c=Integer.valueOf(t1.getText());
if(c==a+ch[i]+b)
{
l2.setText(s1+String.valueOf(c)+"正确!");
}
else
{
l2.setText(s1+String.valueOf(c)+"错误!");
}
t1.setText("");
a=(int)(Math.random()*10);
b=(int)(Math.random()*10);
i=(int)(Math.random()*4);
s1=new String(String.valueOf(a)+String.valueOf(ch[i])+String.valueOf(b)+"=");
l1.setText(s1);
}
public void start()
{}
public void stop()
{}
public void destroy()
{}
public void paint(Graphics g)
{}
}