Re: Bounce off

On Mar 30, 2:42 pm, "Max" <max.di...@gmail.com> wrote:


[snip]

Bellow follows a complete working example with model, view and
controller components.

Pay attention to the OO design implemented.

If I may, I would also suggest a very good book to begin with: D.
Schmidt, Programming principles in Java -- architectures and
interfaces, which can be obtained for free at the following site:

http://www.cis.ksu.edu/santos/schmidt/ppj

Regards,
Faton Berisha

public class MovingBall
{ private int xPos;
  private int yPos;
  private int radius;
  private int xVelocity = 5;
  private int yVelocity = 2;
  private Box container;

  public MovingBall(int xInit, int yInit, int r, Box box)
  { xPos = xInit;
    yPos = yInit;
    radius = r;
    container = box;
  }

  public int xPosition()
  { return xPos; }

  public int yPosition()
  { return yPos; }

  public int radiusOf()
  { return radius; }

  public void move()
  { xPos = xPos + xVelocity;
    if ( container.inHorizontalContact(xPos) )
    { xVelocity = -xVelocity; }
    yPos = yPos + yVelocity;
    if ( container.inVerticalContact(yPos) )
    { yVelocity = -yVelocity; }
  }
}

public class Box
{ private int boxSize;
  public Box(int size)
  { boxSize = size; }

  public boolean inHorizontalContact(int xPosition)
  { return xPosition <= 0 || xPosition >= boxSize; }

  public boolean inVerticalContact(int yPosition)
  { return yPosition <= 0 || yPosition >= boxSize; }

  public int sizeOf()
  { return boxSize; }
}

import java.awt.*;
public class BallWriter
{ private MovingBall ball;
  private Color color;

  public BallWriter(MovingBall b, Color c)
  { ball = b;
    color = c;
  }

  public void paint(Graphics g)
  { g.setColor(color);
    int radius = ball.radiusOf();
    g.fillOval(ball.xPosition() - radius,
      ball.yPosition() - radius, 2 * radius, 2 * radius);
  }
}

import java.awt.*;
public class BoxWriter
{ private Box box;

  public BoxWriter(Box b)
  { box = b; }

  public void paint(Graphics g)
  { int size = box.sizeOf();
    g.setColor(Color.white);
    g.fillRect(0, 0, size, size);
    g.setColor(Color.black);
    g.drawRect(0, 0, size, size);
  }
}

import javax.swing.*;
import java.awt.*;
public class AnimationWriter extends JPanel
{ private BoxWriter boxWriter;
  private BallWriter ballWriter;

  public AnimationWriter(BoxWriter bx, BallWriter bl, int size)
  { boxWriter = bx;
    ballWriter = bl;
    JFrame f = new JFrame();
    f.getContentPane().add(this);
    f.setTitle("Topi k=EBrcyes");
    f.setSize(size, size);
    f.setVisible(true);
  }

  public void paintComponent(Graphics g)
  { boxWriter.paint(g);
    ballWriter.paint(g);
  }
}

public class BounceController
{ private MovingBall ball;
  private AnimationWriter writer;

  public BounceController(MovingBall b, AnimationWriter w)
  { ball = b;
    writer = w;
  }

  public void runAnimation()
  { while ( true )
    { delay(20);
      ball.move();
      writer.repaint();
    }
  }

  private void delay(int milisecs)
  { try { Thread.sleep(milisecs); }
    catch (InterruptedException e) { }
  }
}

import java.awt.*;
public class TestBouncingBall
{ public static void main(String[] args)
  { int boxSize = 200;
    int ballRadius = 6;
    Box box = new Box(boxSize);
    MovingBall ball = new MovingBall(boxSize / 3, boxSize / 5,
      ballRadius, box);
    BallWriter ballWriter = new BallWriter(ball, Color.red);
    BoxWriter boxWriter = new BoxWriter(box);
    AnimationWriter writer = new AnimationWriter(boxWriter,
      ballWriter, boxSize);
    new BounceController(ball, writer).runAnimation();
  }
}