JPanel上设置背景图片

import?java.awt.*;
import?javax.swing.*;
public?class?ImageJPanel?extends?JPanel{
private?Image?image;

public?ImageJPanel(Image?image){?//首先构建一个构造方法.传入的参数是Image的文件路径
??this.image=image;
??Dimension?size?=?new?Dimension(image.getWidth(null),
????????????image.getHeight(null));
??setSize(size);??//设置JPanel的大小为Image图象的大小
??setPreferredSize(size);
??setMaximumSize(size);
??setMinimumSize(size);
}
protected?void?paintComponent(Graphics?g)?{
??super.paintComponent(g);
??g.drawImage(image,0,0,null);?//用G?把Image画出来?
}
public?static?void?main(String[]args){
??ImageJPanel?imageJP?=?new?ImageJPanel(new?ImageIcon("Image/***.jpg").getImage());
??JFrame?jf?=?new?JFrame();
??jf.add(imageJP);
??jf.setSize(imageJP.getWidth(),imageJP.getHeight()+35);//这里+35?是因为JFrame上会有个标题栏?他会占35像素
??jf.setVisible(true);
}
}