一个简单的GUI

[eviliw]

这个简单的窗口怎么画不出线来？
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.util.*;

class RGBFrame extends JFrame implements MouseListener
{
int sign;
JPanel jp;
Graphics panelgraph;
Dimension screensize;
public void init()
{
sign=0;
jp=new JPanel();

screensize=Toolkit.getDefaultToolkit().getScreenSize();

}

public RGBFrame()
{
super();
init();
setUndecorated(true);
pack();
setSize(screensize);
getContentPane().add(jp);
panelgraph=jp.getGraphics();
draw(panelgraph);
}
public void draw(Graphics g)
{
panelgraph.setColor(Color.red);
panelgraph.drawLine(100,100,200,300);
}
public void mousePressed(MouseEvent e)
{

}
public void mouseClicked(MouseEvent e)
{
}
public void mouseReleased(MouseEvent e)
{
}
public void mouseExited(MouseEvent e)
{
}
public void mouseEntered(MouseEvent e)
{
}
public void paint(Graphics g)
{
draw(panelgraph);

}
public void Update(Graphics g)
{
paint(g);
}


}
public class GUITest {
public static void main(String args[])
{
(new RGBFrame()).setVisible(true);

}
}

[diazo]

paint中增加父类的调用

[jaddy]

super.paint(g)

[eviliw]

这样改了还是不行
public void paint(Graphics g)
{
super.paint(panelgraph);//这里应该是g还是panelgraph
draw(panelgraph);//这里应该是g还是panelgraph

}

Update函数这样写对吗？
public void Update(Graphics g)
{
paint(g);
}



哪位大哥帮我改好一下？谢谢

[eviliw]

Update(Graphics g) 应该是小写update(Graphics g)但是该过来还是不行

[eviliw]

能不能说详细点啊？

[wenming168]

用repaint()

[eviliw]

还没有搞定，到底该怎么写？