How to use/create icons with transparent background ?

Question

I would like to use icons with transparent background on JButtons, but I can't find how to do it. Until now, I've been using the ImageIcon class to create icons from GIF images. These images were created with MSPaint (sorry, I don't know what I could have used instead of that). Here is how I create my buttons :
bPencil = new JButton(new ImageIcon("Pencil.GIF"));What could I do to make the background transparent and/or what software could I use instead of M$Paint ?
P.S. : sorry if my question seems silly, but I'm a newbie in Java coding...

Answer 1

Transparent images are GIF (256 colours) and PNG (true-colour, half transparency).
You can store the image with your code, *.class files. You then even can deliver all inside a clickable, executable .jar file.
This kind of usage is called "resource," and hence use getResource like this:
    java.net.URL imgURL = getClass().getResource("pencil.gif");
    ImageIcon icon = null;
    if (imgURL != null) {
        icon = new ImageIcon(imgURL, description);
    }You can use paths.
There exist versions of MSPaint that easily loose their transparent colour on saving.
For GIFs try internet palettes, or try to save as PNG (recent version).
Start with a transparent image from elsewhere.