运行以下代码时,我看不到红色的背景色。它显示默认值。我需要在这些行中添加任何内容吗?
enter code here
import java.awt.*;
import java.awt.Graphics;
import javax.swing.*;
public class gfix extends JPanel {
@Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
g.setColor(Color.red);
g.fillRect(80, 100, 150, 75);
}
public static void main(String[] args){
gfix gg=new gfix();
JFrame frame = new JFrame("RISK");
frame.setSize(800, 600);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel panel = new JPanel();
panel.setLayout(null);
frame.add(panel);
JButton button = new JButton("test");
button.setBounds(100, 100, 150, 150);
panel.add(button);
frame.setVisible(true);
}
}
您正在覆盖painGraphics()
类中的gfix
,因此将gfix
类对象添加到框架中,而不是Java提供的JPanel
类对象。
gfix gg=new gfix();
JFrame frame = new JFrame("RISK");
frame.setSize(800, 600);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//JPanel panel = new JPanel(); Not needed
//panel.setLayout(null);
frame.add(gg);
JButton button = new JButton("test");
button.setBounds(100, 100, 150, 150);
gg.add(button);
frame.setVisible(true);