不知道那错了，指点
程序代码：
import java.applet.*;
import java.awt.*;
import java.awt.event.*;
class draw extends Canvas
{
int shape=0;
public void paint(Graphics g)
{
super.paint(g);
switch (shape)
{
case 1:g.drawRect(100,100,100,100);break;
case 2:g.drawOval(50,5,50,50);break;
}
}
public void img(int shape)
{
this.shape=shape;
}
}
public class exp30 extends Applet implements ActionListener
{
Button rect=new Button("矩形");
Button oval=new Button("椭圆");
public draw dr=new draw();
public void init()
{
Panel p=new Panel(new FlowLayout());
p.add(rect);p.add(oval);
this.setLayout(new BorderLayout());
this.add("North",p);
this.add("Center",dr);
rect.addActionListener(this);
oval.addActionListener(this);
}
public void actionPerformed(ActionEvent e)
{
if(e.getSource()==rect)
dr.img(1);
else if(e.getSource()==oval)
dr.img(2);
}
}
html
程序代码：
<html><applet height="400" width="400" code="exp30.class"></applet></html>
现在的问题是 在applet里面点击两个按钮根本没有任何显示，初步估计是
程序代码：
public void paint(Graphics g)
{
super.paint(g);
switch (shape)
{
case 1:g.drawRect(100,100,100,100);break;
case 2:g.drawOval(50,5,50,50);break;
}
}
{
super.paint(g);
switch (shape)
{
case 1:g.drawRect(100,100,100,100);break;
case 2:g.drawOval(50,5,50,50);break;
}
}
这里有问题，但是在找不出问题所在，求帮助
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晕死，少了个
this.repaint();
悲催，又自己结贴
----------------解决方案--------------------------------------------------------