Re: paint program using canvas

From:
Lew <noone@lewscanon.com>
Newsgroups:
comp.lang.java.programmer
Date:
Sun, 16 Aug 2009 10:57:14 -0400
Message-ID:
<h696oa$rba$1@news.albasani.net>
Knute Johnson wrote:

import java.awt.*;
import java.awt.event.*;

public class test extends Canvas {


Class names should start with an upper-case letter.

    public test() {
        setPreferredSize(new Dimension(640,480));
    }

    public void paint(Graphics g2d) {
        Graphics2D g = (Graphics2D)g2d;

        g.setColor(Color.GREEN);
        g.drawLine(10,getHeight()/2,getWidth()-10,getHeight()/2);

        g.setColor(Color.RED);
        g.setStroke(new BasicStroke(6.0f));
        g.drawLine(10,10,getWidth()-10,getHeight()-10);

        g.setColor(Color.BLUE);
        g.setStroke(new BasicStroke(2.0f));
        g.drawLine(getWidth()-10,10,10,getHeight()-10);
    }

    public static void main(String[] args) {
        final Frame f = new Frame();


Graphic events should occur only on the EDT.

        f.addWindowListener(new WindowAdapter() {
            public void windowClosing(WindowEvent we) {
                f.dispose();
            }
        });

        test t = new test();
        f.add(t,BorderLayout.CENTER);
        f.pack();
        f.setVisible(true);
    }
}


For the sake of future newsgroup denizens it is best to show good practices,
at least the simple ones.

--
Lew

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