将图标添加到 JFrame 时出现问题

Question

I have tried several methods to add an Icon to a JFrame. Every method work perfectly when I run it using the source code.

for example:

jframe.setIconImage(Toolkit.getDefaultToolkit().getImage("iconimages/icon.png"));

But none of them work when I run it using the jar file. I know the problem is with the path of the image file. How can I solve this?

Edit:

public Ui() { 
   initComponents(); 
   setLocationRelativeTo(null); 
   this.setIconImage(getImageIcon("icon.png").getImage());
} 

private ImageIcon getImageIcon(String fileName) {
   String imageDirectory = "iconimages/"; 
   imgURL = getClass().getResource(imageDirectory + fileName); 
   return new ImageIcon(imgURL); 
}

I tried this but now I get a null pointer exception.

--------------------------------------------------------------------------------

Edit [Solution]: I found the solution.

I added ../ to the path additionally and it works perfectly:!! :D

 ImageIcon imageIcon = new ImageIcon("../imageicons/icon.png");
 this.setIconImage(imageIcon.getImage());

Thanks all for try to help me. :)

Answer 1

You should use a URL. Like this:

 /**
  * Loads and returns an {@link Image} resource. 
  * @param fileName name of the image resource.
  * @return Image as resource.
  */
  public Image getResourceImage(String fileName) {
      String imageDirectory = "images/";
      URL imgURL = getClass().getResource(imageDirectory + fileName);
      Image image = null;
      try {
         image = ImageIO.read(imgURL);
       } catch (IOException e) {}
      return image;
    }