运行时总是报错，请看看，请教

Question

应该是没有CardLayout所在的类吧

Answer 1

照下面这样写，先set CardLayout
add时要跟一个字符串

p1.setLayout(Card);
p1.add(lbl1,"one");
p1.add(lbl2,"two");parent 是p1,不是parentif(e.getSource()==btn1)
       Card.previous(p1);
    if(e.getSource()==btn2)
       Card.next(p1);完整代码为import java.applet.*;
import java.awt.*;
import java.awt.event.*;public class test6 extends Applet implements ActionListener
{
Button btn1,btn2;
CardLayout Card = new CardLayout();
FlowLayout Flow = new FlowLayout();
Label lbl1,lbl2;
Panel p1,p2;
public void init()
{
setLayout(new BorderLayout());

p1=new Panel();
p2=new Panel();
p1.setBackground(Color.gray);
p2.setBackground(Color.gray);
add("Center",p1);
add("South",p2);

lbl1=new Label("第一张页面",1);
lbl2=new Label("第二张页面",1);

p1.setLayout(Card);
p1.add(lbl1,"one");
p1.add(lbl2,"two");


btn1=new Button("上一页");
btn2=new Button("下一页");
p2.add(btn1);
p2.add(btn2);
p2.setLayout(Flow);

btn1.addActionListener(this);
btn2.addActionListener(this);
}
public void actionPerformed(ActionEvent e)
{
if(e.getSource()==btn1)
Card.previous(p1);
if(e.getSource()==btn2)
Card.next(p1);
}
}