Re: how to clear the image from jpanel

From:
Knute Johnson <nospam@rabbitbrush.frazmtn.com>
Newsgroups:
comp.lang.java.programmer
Date:
Thu, 28 Oct 2010 09:07:33 -0700
Message-ID:
<ddhyo.3138$lM.1269@newsfe23.iad>
On 10/28/2010 6:30 AM, jimgardener wrote:

I have an ImagePanel subclassed from JPanel ,where I can set an image

class ImagePanel extends JPanel{
    private BufferedImage bi;
    public ImagePanel(){
        super();
    }
    public void setImage(String imagefilename) throws IOException{
        bi = ImageIO.read(new File(imagefilename));
        this.setPreferredSize(new Dimension(bi.getWidth(),bi.getHeight()));

        this.revalidate();
        this.repaint();
         }
        @Override
    public void paintComponent(Graphics g) {
         g.setColor(getBackground());
         g.fillRect(0,0,getWidth(),getHeight());
         g.drawImage(bi,0,0,null);
         }
}

I can set the image by giving an image filename.But I wish to clear
the previous image from the panel,thus showing a blank image panel,if
a user supplies an invalid image name.
How can I do this?Can someone please tell me?
thanks

jim


If no image gets loaded, set the reference to null and test for that in
the paintComponent() method and don't draw the image just clear the
background.

--

Knute Johnson
email s/nospam/knute2010/

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