Swift 2 PhysicsBody not working - swift2

Question

i have a code where i two spaceships floating around the screen however they can't break through the top of the screen and the motto. however they can fly through i sides. i've look at endless about of sites and done some many different types of skphysicsbodys but none of them help.
code example.
class GameScene: SKScene, SKPhysicsContactDelegate {
var player = SKSpriteNode(imageNamed: "spaceship.png")
var player2 = SKSpriteNode(imageNamed: "spaceship.png")
var timer = NSTimer()
var tapsValid:Bool?
var playerRight:Bool?
var playerChange:Bool?
override func didMoveToView(view: SKView) {
let sceneBody = SKPhysicsBody(edgeLoopFromRect: self.frame)
sceneBody.friction = 0
self.physicsBody = sceneBody
physicsWorld.gravity = CGVector(dx: 0.0, dy: 0.0)
tapsValid = true
playerRight = true
self.scene?.backgroundColor = UIColor.whiteColor()
player.position = CGPointMake(self.size.width / 2, self.size.height / 1.8 + 280)
player.physicsBody = SKPhysicsBody(rectangleOfSize: player.size)
player.physicsBody?.dynamic = false
player.physicsBody?.affectedByGravity = false
player.physicsBody?.restitution = 1
player.physicsBody?.friction = 0
player.physicsBody?.linearDamping = 0
player.physicsBody?.angularDamping = 0
player2.position = CGPointMake(self.size.width / 2, self.size.height / 14)
player2.physicsBody = SKPhysicsBody(rectangleOfSize: player2.size)
player2.physicsBody?.affectedByGravity = false
player2.physicsBody?.dynamic = false
player2.physicsBody?.restitution = 1
player2.physicsBody?.friction = 0
player.physicsBody?.linearDamping = 0
player.physicsBody?.angularDamping = 0
self.addChild(player)
self.addChild(player2)
can anyone help me out here. i just want to add physics to the edges of the screen. Thanks,

Answer 1

You should define your colliderTypes and categories for your nodes. That way you can check to see what hits what
enum ColliderType: UInt32 {
case Spaceship = 0
case CornerCategory = 1
}
self.physicsBody!.categoryBitMask = ColliderType.CornerCategory.rawValue
player.physicsBody?.contactTestBitMask = ColliderType.CornerCategory.rawValue
player2.physicsBody?.contactTestBitMask = ColliderType.CornerCategory.rawValue
func didBeginContact(contact: SKPhysicsContact) {
if contact.bodyA.categoryBitMask < contact.bodyB.categoryBitMask {
//If it is true. Means that bodyA is the spaceship. Because it's 0
firstBody = contact.bodyA
secondBody = contact.bodyB
}else{
//Either way. firstBody will always be the spaceship
firstBody = contact.bodyB
secondBody = contact.bodyA
}
if firstBody.categoryBitMask == ColliderType. Spaceship.rawValue && secondBody.categoryBitMask == ColliderType.CornerCategory.rawValue{
//means that Spaceship and wall touches
print("Spaceship hits wall")
}
}