Go语言视频零基础入门到精通

javalearner

载入图片的几种常用方法
   
/**
   
* <p>Title: PaintPanel</p>
   
* <p>Description:此程序演示如何载入图片,并让其作为panel的背景</p>
   
* <p>Copyright: Copyright (c) 2005</p>
   
* <p>Company: gift2u</p>
   
* @author liwu chinajavaworld
   
* @version 1.0
   
*/
   
import javax.swing.*;
   
import java.awt.Graphics;
   
import java.awt.Graphics2D;
   
import java.awt.Image;
   
import java.net.URL;
   
import java.net.*;
   

   
import java.awt.MediaTracker;
   
import java.io.File;
   
import javax.imageio.ImageIO;
   
import java.io.*;
   
import java.awt.Toolkit;
   

   
public class PaintPanel
   
     extends JPanel {
   
   Image image = null;
   

   
   /**
   
    * PaintPanel
   
    * 外部给图片，直接载入
   
    * @param image Image
   
    */
   
   public PaintPanel(Image image) {
   
     this.image = image;
   
   }
   

   
   /**
   
    * PaintPanel
   
    * 外部给出file引用,通过ImageIO载入
   
    * @param file File
   
    */
   
   
   

   
  
  
  public PaintPanel(File file) {
     try {
       Image readImage = ImageIO.read(file);
       this.image = readImage;
     }
     catch (IOException ex) {
     }
   }
  
/**
    * PaintPanel
    *外部给出string路径，通过Toolkit载入
    * @param string String
    */
   public PaintPanel(String string) {
     URL url = null;
     try {
       url = new URL(string);
     }
     catch (MalformedURLException ex) {
     }
     image = Toolkit.getDefaultToolkit().getImage(url);

     MediaTracker tracker = new MediaTracker(this);
     tracker.addImage(image, 0);
     try {
       tracker.waitForID(0);
     }
     catch (InterruptedException ie) {
     }

   }

   /**
    * PaintPanel
    *外部给出ImageIcon，利用ImageIcon载入
    * @param icon ImageIcon
    */
   public PaintPanel(ImageIcon icon) {
     this.image = icon.getImage();
   }

   /**
    * PaintPanel
    * 外部给出URL，利用ImageIcon载入
    * @param icon url
    */
   public PaintPanel(URL url) {
     ImageIcon icon = new ImageIcon(url);
     this.image = icon.getImage();
   }

   public void paintComponent(Graphics g) {
     super.paintComponent(g);
     Graphics2D g2d = (Graphics2D) g;
     if (image != null) {
       g2d.drawImage(image, 0, 0, this);
     }
   }
}
  
  
  测试代码: import javax.swing.JFrame;
import java.net.URL;
import javax.swing.ImageIcon;
import java.awt.MediaTracker;
import java.awt.Image;
import java.net.MalformedURLException;
import java.awt.GridLayout;
import javax.swing.JDialog;
import java.io.File;

public class TestPaintPanel  {
  public static void main(String[] args) {
    JFrame fr = new JFrame();
    fr.setTitle("GIFT-PaintPanel-演示载入图片的方法");
    String urlstr = "http://photo.sohu.com/20040823/Img221677764.jpg";
    String filestr="D://a.jpg";
//如果是自己的机器上...un comment following......
//   String urlstr="file:///D://a.jpg";
    URL url = null;
    try {
      url = new URL(urlstr);
    }
    catch (MalformedURLException ex) {
    }

    ImageIcon icon = new ImageIcon(url);

    //////////////////loadimage//////////////////////
    Image image = fr.getToolkit().getImage(url);
    MediaTracker tracker = new MediaTracker(fr);
    tracker.addImage(image, 0);
    try {
      tracker.waitForID(0);
    }
    catch (InterruptedException ie) {}
    ////////////////////////////////////////////////
    fr.getContentPane().setLayout(new GridLayout(2, 2));
    fr.setSize(500, 600);

    fr.getContentPane().add(new PaintPanel(image));
    fr.getContentPane().add(new PaintPanel(urlstr));
    fr.getContentPane().add(new PaintPanel(icon));
    fr.getContentPane().add(new PaintPanel(url));
    //this is a litter different...
    JDialog dialog = new JDialog(fr, "GIFT-演示让图片成为背景", true);
    //本机上的文件...
    dialog.getContentPane().add(new PaintPanel(new File(filestr)));
    dialog.setSize(200, 200);

    fr.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
    fr.setVisible(true);
    dialog.setVisible(true);
    fr.validate();
  }

}[/code] : 运行图:




  
  
   
   

     
   

     
   
  

  

  










源码下载：http://file.javaxxz.com/2014/10/30/235711218.zip