Java摇摆在ContentPane中交换ImagePanels

Question

I have a set of images that I want to present in a JFrame. They are all the same size - each image fills the JFrame. I swap between which is visible, layer style:

    f = new JFrame("xx");
    f.setSize(480, 854);
    contentPane = f.getContentPane();
    ip1 = new ImagePanel(new File("assets/1.jpg"));
    ip2 = new ImagePanel(new File("assets/2.jpg"));
    ip3 = new ImagePanel(new File("assets/3.jpg"));
    f.setVisible(true);
    contentPane.add(ip1);
    contentPane.addMouseListener(mouseListener);

An ImagePanel is:

public class ImagePanel extends JPanel {
    private BufferedImage image;

    @Override
    public void paintComponent(Graphics g) {
        g.drawImage(image, 0, 0, null);
    }

    public ImagePanel(File imageFile) {
        try {
            image = ImageIO.read(imageFile);
        } catch (IOException e) {
            System.out.println("Image could not be read: " + imageFile);
        }
        setVisible(true);
    }
}

And I try swapping between them in the MouseListener:

static MouseListener mouseListener = new MouseListener() {

    private int i = 1;

    @Override
    public void mouseClicked(MouseEvent e) {
        // logger.log(Level.INFO, e.toString());
        contentPane.removeAll();
        if (++i > 3) i = 1;
        switch (i) {
            case 1: contentPane.add(ip1); break;
            case 2: contentPane.add(ip2); break;
            case 3: contentPane.add(ip3); break;            
        }
        contentPane.repaint();
    }
};

The first image displays as desired. Click gives me white, and same on 2nd click, and third brings me back round to my first image as desired. If I click on the frame in between clicks on the white, the 2nd and 3rd images appear, and once rendered it works as expected. What am I missing?

Ack, newbs! No doubt there is a much better way...

thanks

Answer 1

将两个面板都放在CardLayout 。

Answer 2

put your Images as Icon to the JLabel ,

rulles for Swing GUI

• is JComponent(s) already visible
• you want to swap betweens this/these Object(s)

then you have to call

myLabel.setIcon(myIconn);
revalidate();
repaint();