我编了两个文件分别是OvalPanel.java和testOvalPanel.java用来画一个圆,程序运行无误(JDK 1.5),但是图像不显示,只有在拖大或者点击最大化时,图像才能显示出来。搞了一天头都大了,请知情者能解释一下(代码如下)?不胜感激//OvalPanel.java文件
import java.awt.*;
import javax.swing.*;public class OvalPanel extends JPanel{ public void paintComponent(Graphics g)
{
super.paintComponent(g);
g.drawOval(10,10,10,10);
}
}
//testOvalPanel.java文件
import java.awt.*;
import javax.swing.*;public class testOvalPanel extends JFrame{
private OvalPanel mypanel;
public testOvalPanel()
{
super("testOvalPanel");
mypanel=new OvalPanel();
mypanel.setBackground(Color.YELLOW); Container container=getContentPane();
container.add(mypanel,BorderLayout.CENTER); setVisible(true);
setSize(100,100);
} public static void main(String args[])
{
testOvalPanel testoval=new testOvalPanel();
testoval.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}
import java.awt.*;
import javax.swing.*;public class OvalPanel extends JPanel{ public void paintComponent(Graphics g)
{
super.paintComponent(g);
g.drawOval(10,10,10,10);
}
}
//testOvalPanel.java文件
import java.awt.*;
import javax.swing.*;public class testOvalPanel extends JFrame{
private OvalPanel mypanel;
public testOvalPanel()
{
super("testOvalPanel");
mypanel=new OvalPanel();
mypanel.setBackground(Color.YELLOW); Container container=getContentPane();
container.add(mypanel,BorderLayout.CENTER); setVisible(true);
setSize(100,100);
} public static void main(String args[])
{
testOvalPanel testoval=new testOvalPanel();
testoval.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}
setVisible(true);
setSize(100,100);
改成
setSize(100,100);
setVisible(true);JDK 1.5.0_09