可以设置背景的JPanel!!

最近在写Swing的程序，对怎么在在Jpanel上放置背景网上大多数是在上面加个JLabel，然后设置JLAbel的Icon！但这样做后，JPanel上加其它组件就不好处理了!于是想到继承JPanel然后再重写paintComponent(Graphics g)和paintChildren(Graphics g)这两个方法,这样就保证了JPanel，最初的状态，想怎么处理其它组件都行了;以下是源代码:

import java.awt.Color;

import java.awt.Graphics;

import java.awt.Graphics2D;

import javax.swing.ImageIcon;

import javax.swing.JPanel;

import javax.swing.JScrollPane;

import javax.swing.ScrollPaneConstants;

public class BackGroundPane extends JPanel {

private ImageIcon imageIcon;

public ImageIcon getImageIcon() {

return imageIcon;

}

public void setImageIcon(ImageIcon imageIcon) {//设置图片

this.imageIcon = imageIcon;

}

public BackGroundPane() {

super();

this.setOpaque(false);

}

protected void paintChildren(Graphics g) {//重绘JPanel下的Components

super.paintChildren(g);

for(int i =0;i<this.getComponents().length;i++){

this.getComponent(i).repaint();

}

g.dispose();

}

protected void paintComponent(Graphics g) {

Graphics2D g2D = (Graphics2D)g;

super.paintComponent(g2D);

if(imageIcon!=null){//绘制背景

g2D.drawImage(imageIcon.getImage(), 0, 0,this.getWidth(),this.getHeight(),this);

}

g2D.dispose();

}

}

在调用的时候只要新建一个对象，然后再调用setImageIcon(ImageIcon imageIcon)方法就是可以绘制背景了，如果没有背景也可以当JPanel！！