Re: Simple Help required....

From:
"Andrew Thompson" <u32984@uwe>
Newsgroups:
comp.lang.java.help
Date:
Thu, 15 Nov 2007 14:16:08 GMT
Message-ID:
<7b40c477070cc@uwe>
TheBigPJ wrote:

I am just trying to entertain myself in java to keep myself interested
in learning it. I want to create a square, and every time I press 'Up'
on the keyboard the square size increases. I can draw everything, but
I am unsure where I would go from there...any hints?


That code does not compile.

D:\Line.java:12: non-static variable x cannot be referenced from a static
context
x = 50;
^
D:\Line.java:13: non-static variable y cannot be referenced from a static
context
y = 100;
^
2 errors

This SSCCE* will. When posting code in future, please
consider posting SSCCEs, and it helps a lot if you add a
little indenting as per normal conventions. But indent
'less', around 2-3 chars per level, and definitely avoid
tab chars.

* <http://www.physci.org/codes/sscce.html>

<sscce>
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;

class Line{

  static private int x;
  static private int y;

  public static void main(String args[])
  {
    x = 50;
    y = 100;

    JPanel face = new JPanel()
    {
      protected void paintComponent(Graphics g)
      {
        super.paintComponent(g);

        g.drawRect (50,50,100,100);
      }
    };
    face.setBackground(Color.WHITE);
    face.setPreferredSize( new Dimension(100, 100) );
    JScrollPane scrollPane = new JScrollPane( face );
    scrollPane.setPreferredSize( new Dimension(200, 200) );

    JFrame frame = new JFrame();
    frame.addKeyListener( new KeyAdapter() {
        public void keyPressed(KeyEvent e) {
          System.out.println(e);
          //what do I do here???
          // read the output..
          // consult the JavaDocs..
          // formulate theories..
          // test the theories in code..
          // if you get stuck, get back to us
          // with a specific question.
        }
      } );
    frame.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
    frame.getContentPane().add( scrollPane );
    frame.pack();
    frame.setLocationRelativeTo( null );
    frame.setVisible( true );
  }
}
</sscce>

--
Andrew Thompson
http://www.athompson.info/andrew/

Message posted via JavaKB.com
http://www.javakb.com/Uwe/Forums.aspx/java-setup/200711/1

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