Transparency with png file

Question

Hello,
I created png file in Corel Draw (its simple logo in two colors) and save it with some transparency. What I want to do is: load it in java and put it into my program. Easy. But the problem is, that the transparency doesn't work.
I'm using this code:
     private void init() {
          try {
               img = ImageIO.read(getClass().getResource(source));
          } catch (IOException exc) {
               JOptionPane.showMessageDialog(null,exc.getMessage());
      * Default paint method for this component.
     public void paint(Graphics g) {
          g.drawImage(img,0,0,null,this);
     }Where source is "/logo.png"
It is simple "component" which I'm simply adding it to ContentPane in my applet.
Any ideas? Thanks.
A. J.

Answer 1

Well,
in that case I don't understand where is problem. As I mentioned above I've created image in Corel Draw. After that I exported it to .png file. During exporting I set the white color to be transparent. After I saved it I checked the image in Gimp, where that color was transparent. So I'm presuming that the image is all right.
I've read something about alpha value in pictures. I'm not sure if I don't confusing this two things together...? So I'd like to explain what I'm trying to do.
I have picture (logo) with two colors, blue and white. I wan to to draw it in my applet as only blue logo onto background.
Here's my code:
public class Logo extends JComponent {
     private BufferedImage img;
     private String source = "/logo.png";
      * This method initializes this component.
     private void init() {
          try {
               img = ImageIO.read(getClass().getResource(source));
          } catch (IOException exc) {
               JOptionPane.showMessageDialog(null,exc.getMessage());
     public void paintComponent(Graphics g) {
          g.drawImage(img,0,0,null,this);
      * Default constructor.
     public Logo() {
          init();
     public Logo(String source)
          this.source = source;
          init();
     }After that I want to put this logo into my applet. I'm using this code:
      * This is the default constructor
     public Java_applet() {
          super();
      * This method initializes this
      * @return void
     public void init() {
          this.setSize(670, 500);
          this.setContentPane(getJContentPane());
     private JPanel getJContentPane() {
          if (jContentPane == null) {
               jContentPane = new JPanel();
               jContentPane.setLayout(null);
               jContentPane.add(getLogo(),null);
          return jContentPane;
     private Logo getLogo() {
          if (logo == null)
               logo = new Logo();
          logo.setLocation(new java.awt.Point(0,0));
          logo.setSize(new java.awt.Dimension(670,50));
          return logo;
     }I hope now it's more clear what I'm trying. Thanks for any ideas.
A. J.