simple GUI problem

[apahliani]

I´ve written the following class ShowImage to put image on the screen but what I got was a blank window.Why could not I see the image on the screen?



import javax.swing.*;
import java.awt.*;


public class ShowImage extends JFrame {

public static void main(String[ ] args) {*

ShowImage si=new ShowImage();
Graphics g=si.getGraphics();
Image im;
Toolkit T=si.getToolkit();
im=T.getImage("Jumbo.jpg");
g.drawImage(im, 50,50,si);
}
public ShowIm(){
this.setSize(770, 420);
this.setVisible(true);
}
}

[sjalle]

You've not extended the JFrame class properly, you must override its paint(Graphics g) method. Drawing an image one time doesn't make it stick

public static void main(String[ ] args) {*

ShowImage si=new ShowImage();
Image im;
Toolkit T=si.getToolkit();
im=T.getImage("Jumbo.jpg");
}
public ShowIm(){
this.setSize(770, 420);
this.setVisible(true);
}
public void paint (Graphics g) {
g.drawImage(im, 0,0,this);
}
}