How to add more blocks - xcode

Question

I tried adding var square, and all the things I did for squareView. But all I am getting is one box falling and the other just standing there. Is there an easier way to add another box which does the same action as squareView?
import UIKit
class interestViewController: UIViewController {
var squareView: UIView!
var square: UIView!
var gravity: UIGravityBehavior!
var animator: UIDynamicAnimator!
var collision: UICollisionBehavior!
override func viewDidLoad() {
super.viewDidLoad()
squareView = UIView(frame: CGRectMake(100, 100, 100, 100))
square = UIView(frame: CGRectMake(200, 100, 100, 100))
squareView.backgroundColor = UIColor.blackColor()
square.backgroundColor = UIColor.blackColor()
view.addSubview(square)
view.addSubview(squareView)
animator = UIDynamicAnimator(referenceView: view)
animator = UIDynamicAnimator(referenceView: view)
gravity = UIGravityBehavior(items: [squareView])
gravity = UIGravityBehavior(items: [square])
animator.addBehavior(gravity)
animator.addBehavior(gravity)
collision = UICollisionBehavior(items: [squareView])
collision = UICollisionBehavior(items: [square])
collision.translatesReferenceBoundsIntoBoundary = true
animator.addBehavior(collision)
// Do any additional setup after loading the view.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}

Answer 1

This code is sheer nonsense:
gravity = UIGravityBehavior(items: [squareView])
gravity = UIGravityBehavior(items: [square])
animator.addBehavior(gravity)
animator.addBehavior(gravity)
When you set the variable gravity to one behavior and to another behavior right in a row, the first behavior is just thrown out as if it never existed. So naturally when you get around to adding the behaviors, there is only one behavior to add: the one gravity that is left (which you then, even more nonsensically, add twice). So naturally only one block is animated.
Think of it more simply this way:
var x = 0
x = 1
x = 2
Now, what is the value of the variable x? If you think it is 0 and 1 and 2, you have not understood what a variable is.