// This is a code fragment that shows how to use an ArrayList.

// It won't compile because it's missing the Ball class.



ArrayList balls;



void setup() {

  size(200, 200);

  balls = new ArrayList();  // Create an empty ArrayList

  balls.add(new Ball(width/2, 0, 48));  // Start by adding one element

}



void draw() {

  background(255);



  // With an array, we say balls.length, with an ArrayList, 

  // we say balls.size(). The length of an ArrayList is dynamic. 

  // Notice how we are looping through the ArrayList backwards, this 

  // is because we are deleting elements from the list  

  for (int i = balls.size()-1; i >= 0; i--) { 

    // An ArrayList doesn't know what it is storing so we have 

    // to cast the object coming out

    Ball ball = (Ball) balls.get(i);

    ball.move();

    ball.display();

    if (ball.finished()) {

      // Items can be deleted with remove()

      balls.remove(i);

    }

  }  

}



void mousePressed() {

  // A new ball object is added to the ArrayList, by default to the end

  balls.add(new Ball(mouseX, mouseY, ballWidth));

}