Re: Help : ImageIcon constructor fails to load image

Rhino wrote: 
"AlecB" <nobodyhere@xxxxxxxxxx> wrote in message
news:dk2qel$ras$1@xxxxxxxxxxxxxxxxxx

Hi,

I am attempting to familiarising myself with swing and have encountered
a strange problem.

The problem is that when I attemp to instantiate an Imageicon with a
relative filename. it fails.


e.g.
- images/
- icon.gif
- ImageLabelExample.class

I suspect its something simple. Can someone point out what I'm missing?

Thanks.

Code snippet ... (from www.oreilly.com/swing2)


This link produces a '404' error when I attempt to view the page. Perhaps
the site is down temporarily?


...

public static main(String[] args){
JLabel[] labels = new JLabel[3];
labels[0] = makeLabel(JLabel.TOP, JLabel.LEFT);
labels[1] = makeLabel(JLabel.TOP, JLabel.CENTER);
labels[2] = makeLabel(JLabel.TOP, JLabel.RIGHT);
// disable label 0
labels[0].setEnabled(false);
// Fails to find the image, the image is in the .jar file
//labels[1].setDisabledIcon(new ImageIcon("images/icon.gif"));
// This works
      labels[1].setDisabledIcon(creatImageIcon("images/icon.gif",null));
for(int i = 0; i < labels.length; i++)
   c.add(labels[i]);
frame.setSize(350, 350);
frame.setVisible(true);
}

protected static JLabel makeLabel(int vert, int horiz) {
    JLabel l = new JLabel("Smile", icon, SwingConstants.CENTER);
    l.setVerticalTextPosition(vert);
    l.setHorizontalTextPosition(horiz);
    l.setBorder(BorderFactory.createLineBorder(Color.black));
    return l;
}

// If I create the ImageIcon here, all is well
protected static ImageIcon createImageIcon(final String path, String
description) {
    java.net.URL imgURL = ImageLabelExample.class.getResource(path);
    System.err.println( imgURL );
    if (imgURL != null) {
        return new ImageIcon(imgURL, description);
    } else {
        System.err.println("Couldn't find file: " + path);
        return null;
    }
}



Basically, the technique for getting an image out of a file in the
filesystem is slightly different than the technique for getting a jar entry
out of a jar in the classpath.

The code in your 'createImageIcon()' method is correct for getting a jar
entry out of a jar in the classpath. If your image is indeed in a jar on the
classpath, then you have nothing further to do.

However, if you want to get your image from a relative location within your
local filesystem, you need to do things just a little differently, something
like this (untested!):

String fileLocation = "images/icon.gif"; //location of file expressed as a
String
File imageFile = new File(fileLocation); //create a File reference to that
location
URL imageFileUrl = imageFile.toUR(); //create a URL pointing to the file
labels[1].setDisabledIcon(new ImageIcon(imageFileUrl)); //get the image from
its URL

Rhino


Oops,

That link should be http://www.oreilly.com/catalog/jswing2/
The source can be found in the chapter 4 bit of the code examples.

Of course this mechanism for creating imageicons is used throughtout the book, so I thought wisest to clarify.

Thanks.
.

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