JAVA - Add an image to JPanel

Question

I'm new in JAVA. I would like to get an image in my window (JPanel) for working on it (add circles for example). I created a menu and when I click in "File>Import", the open dialog box is appearing to choose my image. I get the right path to the image file (checked thanks to System.out.println(FC.getSelectedFile().toString());) but the image doesn't appear...

Here is the code :

        //On crée les listeners pour le menu "Fichier" :
        this.importer.addActionListener(new ActionListener()
        {
              public void actionPerformed(ActionEvent event)
              {
                  //On ouvre la boîte de dialogue pour charger le dessin :
                  JFileChooser FC = new JFileChooser();
                  FC.showOpenDialog(null);
                  BufferedImage myPicture=null;
                try {
                    myPicture = ImageIO.read(FC.getSelectedFile());
                    System.out.println(FC.getSelectedFile().toString());
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
                  contenant.add(new JLabel(new ImageIcon(myPicture)), BorderLayout.CENTER);
                  contenant.repaint();
              }
          });

Thanks for your support.

try to post just relevant part of the code, here Image relevant part — kolboc, Aug 20 '16 at 10:23
Possible duplicate of [How to add an image to a JPanel?](http://stackoverflow.com/questions/299495/how-to-add-an-image-to-a-jpanel) — Andremoniy, Aug 20 '16 at 10:24
In fact, my code seemed to work, but only when I change manually (with mouse) the size of my window... Any idea ? — Fred, Aug 20 '16 at 10:33
maybe you didn't set size for your main frame, you can use pack, but personally I preferred hard coding preferred size. When it doesn't work I used to set minimumSize for my main frame. — kolboc, Aug 20 '16 at 10:35

score 0 · Accepted Answer · answered Aug 20 '16 at 10:37

0

Replace this:

contenant.repaint();

With this:

contenant.revalidate();

When you add the JLabel, it doesn't automatically force the content pane to sort out it's layout, so even though the JLabel is on there, it's not sized yet. Calling revalidate() fixes this.

answered Aug 20 '16 at 10:37

Drewll

318
2
10

Thanks Drewll but in Eclipse I have this error : "The method revalidate() is undefined for the type Container". Indeeed, contenant is a container : private Container contenant;. – Fred Aug 20 '16 at 10:39
I created a JPanel to use revalidate() method. Thanks for your help. – Fred Aug 20 '16 at 11:07

JAVA - Add an image to JPanel

1 Answers1